ESA’s Rosetta spacecraft has made the first in situ detection of oxygen molecules outgassing from a comet, a surprising observation that suggests they were incorporated into the comet during its formation. This news story is mirrored from the main ESA web portal.
Rosetta has been studying Comet 67P/Churyumov–Gerasimenko for over a year and has detected an abundance of different gases pouring from its nucleus. Water vapour, carbon monoxide and carbon dioxide are the most prolific, with a rich array of other nitrogen-, sulphur- and carbon-bearing species, and even ‘noble gases’ also recorded.
Oxygen is the third most abundant element in the Universe, but the simplest molecular version of the gas, O2, has proven surprisingly hard to track down, even in star-forming clouds, because it is highly reactive and readily breaks apart to bind with other atoms and molecules.
For example, oxygen atoms can combine with hydrogen atoms on cold dust grains to form water, or a free oxygen split from O2 by ultraviolet radiation can recombine with an O2 molecule to form ozone (O3).
Despite its detection on the icy moons of Jupiter and Saturn, O2 had been missing in the inventory of volatile species associated with comets until now.
“We weren’t really expecting to detect O2 at the comet – and in such high abundance – because it is so chemically reactive, so it was quite a surprise,” says Kathrin Altwegg of the University of Bern, and principal investigator of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis instrument, ROSINA.
“It’s also unanticipated because there aren’t very many examples of the detection of interstellar O2. And thus, even though it must have been incorporated into the comet during its formation, this is not so easily explained by current Solar System formation models.”
The team analysed more than 3000 samples collected around the comet between September 2014 and March 2015 to identify the O2. They determined an abundance of 1–10% relative to H2O, with an average value of 3.80 ± 0.85%, an order of magnitude higher than predicted by models describing the chemistry in molecular clouds.
The amount of molecular oxygen detected showed a strong relationship to the amount of water measured at any given time, suggesting that their origin on the nucleus and release mechanism are linked. By contrast, the amount of O2 seen was poorly correlated with carbon monoxide and molecular nitrogen, even though they have a similar volatility to O2. In addition, no ozone was detected.
Over the six-month study period, Rosetta was inbound towards the Sun along its orbit, and orbiting as close as 10–30 km from the nucleus. Despite the decreasing distance to the Sun, the O2/H2O ratio remained constant over time, and it also did not change with Rosetta’s longitude or latitude over the comet.
In more detail, the O2/H2O ratio was seen to decrease for high H2O abundances, an observation that might be influenced by surface water ice produced in the observed daily sublimation–condensation process.
The team explored the possibilities to explain the presence and consistently high abundance of O2 and its relationship to water, as well as the lack of ozone, by first considering photolysis and radiolysis of water ice over a range of timescales.
In photolysis, photons break bonds between molecules, whereas radiolysis involves more energetic photons or fast electrons and ions depositing energy into ice and ionising molecules – a process observed on icy moons in the outer Solar System, and in Saturn’s rings. Either process can, in principle, lead to the formation and liberation of molecular oxygen.
Radiolysis will have operated over the billions of years that the comet spent in the Kuiper Belt and led to the build-up of O2 to a few metres depth. But these top layers must all have been removed in the time since the comet moved into its inner Solar System orbit, ruling this out as the source of the O2 seen today.
More recent generation of O2 via radiolysis and photolysis by solar wind particles and UV photons should only have occurred in the top few micrometres of the comet.
“But if this was the primary source of the O2 then we would have expected to see a decrease in the O2/H2O ratio as this layer was removed during the six-month timespan of our observations,” says Andre Bieler of the University of Michigan and lead author of the paper describing the new results in the journal Nature this week.
“The instantaneous generation of O2 also seems unlikely, as that should lead to variable O2 ratios under different illumination conditions. Instead, it seems more likely that primordial O2 was somehow incorporated into the comet’s ices during its formation, and is being released with the water vapour today.”
In one scenario, gaseous O2 would first be incorporated into water ice in the early protosolar nebula stage of our Solar System. Chemical models of protoplanetary discs predict that high abundances of gaseous O2 could be available in the comet forming zone, but rapid cooling from temperatures above –173ºC to less than –243ºC would be required to form water ice with O2 trapped on dust grains. The grains would then have to be incorporated into the comet without being chemically altered.
“Other possibilities include the Solar System being formed in an unusually warm part of a dense molecular cloud, at temperatures of 10–20ºC above the –263ºC or so typically expected for such clouds,” says Ewine van Dishoeck of Leiden Observatory in the Netherlands, co-author of the paper.
“This is still consistent with estimates for the comet formation conditions in the outer solar nebula, and also with previous findings at Rosetta’s comet regarding the low abundance of N2.”
Alternatively, radiolysis of icy dust grains could have taken place prior to the comet’s accretion into a larger body. In this case, the O2 would remain trapped in the voids of the water ice on the grains while the hydrogen diffused out, preventing the reformation of O2 to water, and resulting in an increased and stable level of O2 in the solid ice.
Incorporation of such icy grains into the nucleus could explain the observed strong correlation with H2O observed at the comet today.
“Regardless of how it was made, the O2 was also somehow protected during the accretion stage of the comet: this must have happened gently to avoid the O2 being destroyed by further chemical reactions,” adds Kathrin.
“This is an intriguing result for studies both within and beyond the comet community, with possible implications for our models of Solar System evolution,” says Matt Taylor, ESA’s Rosetta project scientist.
“Abundant molecular oxygen in the coma of 67P/Churyumov–Gerasimenko,” by A. Bieler et al is published in the 29 October 2015 issue of the journal Nature.
Discussion: 357 comments
Interesting stuff, and comes hard on the heels of the announcement that ethyl alcohol (ethanol) and glycoaldehyde were detected at comet Lovejoy: https://advances.sciencemag.org/content/1/9/e1500863.full
All 21 of the complex organic molecules found on Lovejoy have also been detected in molecular clouds.
Hi Ianw16,
From the National Graphics blog – this quote:
“The finding is definitely a wake up call for exoplanets and the search for life,” says Sara Seager of MIT. “O2 is the most prominent gas on our biosignature gas list.”
I’d be more inclined to add comet nuclei as places to look for signs of life based on this discovery, rather than deducting O2 as one of the bio signatures we are looking for.
Hi Marco.
As much as would like to consider spor(e)-adic ‘life-oid’ replicative chemical activity on Ducky’s muds, nothing to ask to Teams.
There are not biological instruments on board.
Mars and Earth have been exchanging collision ejecta from the beginning. So, it is Mars -and not 67P- who is going to bring NECESSARILY that [not my] conversation.
If wanting to meet true ‘martians’ Then needing a good understanding of subterranean terrestrial life 😉
Logan,
Like!
Hi Emily: “a surprising observation that suggests they were incorporated into the comet during its formation.”
Are the Teams considering ongoing Electro-Chemistry [Missing ozone is very disturbing along with molecular oxygen]?
Thanks a lot A. Bieler, K. Altwegg, H. Balsiger, A. Bar-Nun et al. 🙂
[Comes from the inside]
The Team is clear in preference:
“…the preferred explanation of our observations is the incorporation of primordial O2 into the cometary nucleus.”
Accepting and working on it. Not discarding the still present plausibility of ongoing electron chemistry. [As for the actual level of oxygen being so high (almost ‘breathable’)].
Yet another plausibility is that comets are not homogeneous ‘samplings’ of Mother Nebulas’ gas charge. [Primigenial comet-esimals being ‘coagulates’ of their very nucleus, as an example].
This is cometary fiction.
Hi Logan,
At least this result finally rules out the possibility of warm liquid water coming from the interior…… The proportion of molecular oxygen is too much compared to what would be dissolved in water, and you would expect things like CO to me much more corellated because of its higher solubility in water… Or have I got that the wrong way round?
Hi Marco. Not a scientist, you know. But it is d_mn to much oxygen! Impossible to my mind to evade Ducky is an oxygen ‘ark’. [Not discarding another plausible phenomena].
[No need to rule out, Marco. Just scale down your idea].
Mud is extremely relevant for complex organics. The issue is not about quantity, but presence.
Scale is precisely the reason of the great relevance of the document. On suggesting 02 pristine, the ROSINA
Team is also suggesting the possibility of cometary being the most common form of solid state. [hope not being wrong].
Is just me ? Sometimes perceiving a ‘forensic’ attitude on cometary science.
Agreeing with Kathrin on the needed gentleness. As for the neutral gas coming all the way down here scenarios, this surprising document gives a very strong argument for cage-ing clathrates.
Amorphous ices doesn’t sounds very immobilizing, or chemically isolating 🙂
Just saying that after this last wave of preliminary results, now our Pirates have plenty of ‘islands’ to replenish in their wanders.
“Our_ observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance.”
Surely miss-perceiving, but see a slightly significant change in between arriving long all-day-sunny North Summer and cyclic Equatorial Spring [at fig. 3].
South plaque could be less porous. Expecting less gas/water ratio, in general, at perihelion 🙂
Let’s be clear. Heat transfer is not the only elephant in the room.
Interesting. Finally some substantial constraints to the formation of 67P, and maybe of our solar system.
Have the isotopic ratios of neutral H2O and O2 been correlated?
Hi Gerald. Have noted the ‘accretion bursts’ comment?
Should we say solar ‘burps’? 😉
https://phys.org/news/2015-11-protostar-growth-spurts.html
https://www.nature.com/nature/journal/v527/n7576/full/nature15702.html
[It’s a young class 0 proto-Star, curiously result to me that it has a C0 envelope]. Maybe that Mother Nebula is older than ours.
4.6 billion years older than ours has been.
Wondering whether CO can be pyrolysed to C and O during jet formation. Would be another mechanism to form O2.
Proto-Star CARMA-7 is episodically ‘ingesting’ big objects [and growing] on a quasi-regular 1/hundred-years cycle.
Adele L. Plunkett et al. suggest that turbulence of episodic ‘burpings’ of the cluster contribute to kinematics of accretion.
Good grief
If microbial life is ubiquitous on 67P, 67P could have its own Gaia principle in which 4% oxygen is the current steady disequilibrium. It is much harder to explain the constant 4% disequilibrium without life than with life. If not life, what is keeping the atmospheric O2 percentage constant, despite the continual temperature and solar radiation changes the comet has been experiencing?
In fact, James Lovelock suggested long ago that the atmospheric conditions that persist on 67P could be explained only by a terrestrial biota.
https://www.latimes.com/science/sciencenow/la-sci-sn-oxygen-rosetta-comet-20151027-story.html
Here is the money quote, in terms of scientists’ ignoring the glaring evidence right before their eyes:
“As far as we knew the combination of methane and O2 was a hint that you had life, but on our comet we have both methane and O2, but we don’t have life, so it is probably not a very good bio-signature” Altwegg said.
Talk about simply presupposing away the most reasonable explanation with a wave of one’s hand!
Alternative #1:
What all planetary scientists used to consider a clear bio-signature (because it is) is no longer a bio-signature at all. Oxygen and methane can and do persist in a “stable” atmospheric disequilibria indefinitely through some bizarre, unknown, and previously unimagined primordial chemical processes! All of our most prominent solar system formation models need to be rethought, and we need to devise a previously unimagined and currently unknown process for how “primordial” O2 ice somehow managed to get evenly distributed within 67P billions of years ago. We also need to explain how this previously unimagined O2 ice somehow managed to persist undisturbed for billions of years, despite its incredibly reactive nature. Finally, we need to show how such primordial O2 managed to be distributed in such a way to result in constant replenishment to maintain 67P’s stable atmospheric disequilibria, even as its distance from the sun keeps changing.
Alternative #2:
We could just consider the possibility that 67P does indeed have all the previously agreed upon biosignatures of life, and when microbial life infects a comet, it terraforms the comet to achieve a stable atmospheric disequilibria, just as it has on Earth.
Only consensus bias against microbial life existing on comets makes the first alternative more “scientifically conservative” than the second. Both alternatives completely annihilate the current consensus paradigm.
re kelly – annihilate the current paradigm
How did the O2 stay evenly distributed for billions of years?
At the moment if the current paradigm is broken, does it even make sense to rely on the idea that the comet is 4 billion years old especialy if its difficult to expalin the O2.
If the current idea of acretion is bust, maybe this comet was not even around at the beginning, what ever the beginning was.
There must be hundreds of alternatives right now until the dust settles again, both for the formation of comets and the signature of life we need to look out for.
regards
Hi Kelly Duke,
That is not the most of it. Philae hasn’t even been sterilised in the way Mars rovers are. I’ve been pushing for the consideration of the possibility of water, and of stretch to no avail. I don’t see why biota should be any different.
Temperatures below -200°C are a challenging condition for (biologic) metabolism.
Hi Gerald,
This is just another challenge to the reasonableness of the assertion of -200′ C. Until we measure the internal temperature, it remains unknown what a reasonable approximation is.
Hi Marco,
how do abundant supervolatiles survive above minus 200°C at low pressure?
Where does the warmth in the core come from?
Why has the polar night of the comet been below minus 200°C, if the interior is assumed to be warm?
No direct measurement necessary to find a reasonable approximation.
Gerald, re:”how do abundant supervolatiles survive above minus 200°C at low pressure?”
We haven’t measured the internal pressure either, nor whether the “supervolatiles” are in their solid, liquid or gaseous (dissolved) state before outgassing. I suggest by the pattern of outgassing proportional to water, many of them are dissolved in liquid water (eg. O2)
Where does the warmth in the core come from?
I have suggested thermal conduction(of the sun’s heat) through a thick (non-porous) crust rich with PAHs which are as thermally conductive as metal.
Why has the polar night of the comet been below minus 200°C, if the interior is assumed to be warm?
We are only measuring the temperature of the surface devoid of volatiles. Radiative heat loss would overwhelm conduction from the warm interior, at the polar night.
Hi Gerald,
Ammonia, other antifreeze?
Or a virus type “life”?
Also, what about when solar system sails through interstellar heliospheres with million degree electrons flying by, through arms of ourgalaxy, exposed to local super nova events, other sources of hear over billions of years… Could there be temperature fluctuations?
We know viruses can be dead for ages and “wake up”.
What is the mostly sunlit areas temperature right now? Still only minus 200C or much higher on some balmy days not so far from from the sun?
Consider everything!
Correction: …sources of heat… not hear.
Sorry and thanks!
Hi Ramcomet,
ammonia would be frozen, as well, in the core of the comet.
But you are right, that some forms of life can survive for a long time at low temperatures, in an inactive state.
This doesn’t, however, mean evidence for pansperima.
More likely are some pre-biotic molecules on 67P.
Gerald, in other news, but possibly related to ammonia being frozen or not, from New Horizons NASA most recent article about Pluto’s Moon Charon’s enigma crater
:https://www.nasa.gov/feature/the-youngest-crater-on-charon
Not sure what the interior temperature of Charon might be, but the last paragraph of the article states strong possibility of ammonia/water cryovolcanism.
Likely tidal flexing from eccentric orbit around Pluto creates more heat than interior of 67P, but still thought you would find this interesting!
Ramcomet, the Pluto – Charon system is highly interesting, without any doubt.
Pluto and Charon are sufficiently large and sufficiently far away from the Sun to make radiogenic heat (decay of radionuclids) a significant ingredient.
I’ve done a back-of-an-envelope calculation for Plute a while ago, and found radiogenic heat much more relevant for Pluto than for Earth.
Not sure, to which degree the New Horizons team is currently thinking along these lines, but I think, they are well aware of this possibility.
Although radiogenic heat is probably more relevant for the nitrogen and carbon monoxide ice than for ammonia.
Hi Gerald,
I might remind you that unequivocal evidence was found by Stardust of (warm) liquid water. Why does every expert think it was a one off exception?
Hi Marco,
that’s at least some evidence, but:
This aquaeous alteration has either taken place very early, e.g. on an asteroid which later crushed, and parts of which were incorporated into the comet, or during a geologically very short period of time after an impact.
“Heat generated at the site of minor impacts might generate pockets of water in which the sulfides could form very quickly, within about a year (as opposed to millions of years). This could happen at any point in the comet’s history. Radioactive decay on the other hand, would point to a very early formation of the minerals since the radioactive nuclides would decay over time and cause the heat source to flicker out.”
“According to Lauretta, the findings show that comets experienced processes such as heating and chemical reactions in liquid water that changed the minerals they inherited from the time when the solar system was still a protoplanetary disk, a swirling mix of hot gases and dust, before it cooled down enough for planets to form.”
https://www.dailygalaxy.com/my_weblog/2011/04/stardust-mission-comet-discovered-harboring-liquid-water-in-past-1st-ever-found.html
.. And “liquid water” doesn’t need to mean much more than some humidity, e.g. like wet mud.
I’m actually not even quite sure, whether aquaeous alteration is impossible on direct contact of primordial dust with water ice over billions of years, just by some water vapor diffunding out of the ice.
The abundant supervolaties at 67P wouldn’t survive “high” temperatures, not even allowing for significant amounts of very briny water at -70°C.
The supervolatiles may be trapped in clathrates. But melting or just warming the clathrates would free the supervolatiles.
Long periods of proximity to the Sun, needed to warm up the interior of the comet would have freed the supervolatiles, as well. But they are present.
Same with radiogenic heat.
Besides, most of the respective nuclids are decayed in the meanwhile.
The radiogenic heat would be radiated to space, due to heat flux and the small size of 67P, and since the energy per time unit radiated to space is proportional to the 4th power of the (absolute) thermodynamic surface temperature of a body. (See also planetary equilibrium temperature).
“High” core temperatures tody, caused by radiogenic heat, would mean much higher temperature in the past due to the exponential behavior of radioactive nuclids, ruled out by the presence of volatiles.
Other sources of heat (of chemical nature) would be very transient (in geologic terms). Nearby supernovae, too.
“…I’m actually not even quite sure, whether aquaeous alteration is impossible on direct contact of primordial dust with water ice over billions of years, just by some water vapor diffunding out of the ice.”
Quantum wanderings? 🙂
Hi Gerald,
These “supervolatiles”, such as CH4, CO2, O2 and so on, are also substances ubiquitous in the presence of life. So, while under the paradigm of Whipple this is evidence of continuous very cold temperatures over billions of years (falsified by some of your explanations of temporary liquid water which, for instance would have dissipated or reacted the O2) under the warm interior paradigm would be evidence of life (metabolism would cause these supervolatiles to be cycled into and out of biochemical reactions)
So, unless I believed the Whipple paradigm to be unquestionable, I believe the various explanations of temporary liquid water to be questionable.
Surely_ this is a bad rewording. Dr. Altwegg wouldn’t say what is absent at 67P. Specially knowing Mission design, lack of instruments and ultimately not being her field [exo-biology].
Would love that Dr. Altwegg correct that bad reference, Kelly 🙂
Anyhow, search for life answers is more of a ontology quest. Science is going to look for them only in the measure is tasked for.
Logan,
Kelly quoted the article exactly… Maybe you mean L. A. Times misquoted Dr. Altwegg?
Even Kathrin could in the stress of responsibilities of press conference [She is Principal Investigator].
In stressful situations easier is to express feelings than thoughts.
Just check how press comments have been a lot more ‘seasoned’ than the cool and pondered ones of Endorsed Papers.
Kelly… Bravo!
Or possibly something like “life”.
The conditions on 67P preclude the existence of liquid water.except, just conceivably, as an extremely transient species. Its presence is usually consider d a prerequisite for life. The hard UV flux at the surface near herihelion would sterilise the surface very effectively.
There is no clear ‘bio signature’ whatever, and the presence of life improbable in the extreme.
But not impossible, unless I’m reading this article totally wrong, especially toward the bottom:
https://www.space.com/26888-sea-plankton-space-station-russian-claim.html
And who knows, comets might explain where not only earth’s water came from, but also where the mole people came from, which archeologists found in Mesopatamia, as noted in the 1956 documentary, The Mole People.
capta issue, retry.
SS:
Documentary?
“The Mole People is a 1956 science fiction film directed by Virgil W. Vogel.”‘
Sounds like Velikovskian nonsense.
The ability of micro organisms to survive in space in a dormant state is known. But as they are dormant they cant evolve etc. Solar UV would destroy exposed organisms eventually.
Zero is a very special number; so I wouldn’t say ‘impossible’, but its a pretty good approximation; very, very, very unlikely.
Uh, was a very tongue in cheek comment about the mole people, Harvey. Though right now, since no one has actually peaked inside of the comet yet, strictly speaking, the possibility of finding mole people in there is equal to that of finding water, or rock, or micro organisms. Evidence does not constitute fact, and there is always more evidence to gather. But regarding the possibility of organisms pouring sugar into the data gas tank about oxygen, it’s impossible for dormant organisms to perhaps become active below surface as the terrain heats up? Something is apparently skewing the data, seems like the best approach is to list all possible explanations, hold them all in consideration without judgment as more evidence is gathered and falsification can be applied, instead of immediately ruling out anything because it is very very very unlikely.
Sovereign Slave,
usually cases estimated as “exceedingly unikely”, probability below about one in 3 million, are neglected.
Otherwise you would get a list of infinite length, almost all items of zero probability, but not strictly impossible, or worse, all items of non-zero probability, but summing up, as a geometric series, to probability 1, still allowing for an infinite number of unconsidered, but possible, cases.
You see the issue with finite ressources? Chasing exceedingly unlikely possibilities is a waste of time, time you’d better spend to first investigate likely cases.
Maybe transient is enough, then freeze again and again. The jury is out on Mars. Stay tuned!
The high abundance of oxygen may point towards the interstellar gas and dust cloud our solar system formed of, been to a high degree the result of a type Ia supernova of a white dwarf of the carbon-oxygen type:
https://iopscience.iop.org/article/10.1086/305381/fulltext/
Molecular oxygen has been amply accepted among the best of bio-signatures [in exo-biology].
But, if most of it -We came to know just today-, has been molecularly isolated [caged] from the beginning, then how could it be related to biology?
If so, maybe doesn’t deserve to be at the top of that list.
Maybe most of it is only a product of Stars’ evolution, as noble gases actually are.
Hope Dr. Altwegg will come on our help.
On Accepting Rossina Team document, accepting also the plausibility of mineral methane clathrates, too.
Logan and Gerald’s 30-10 posts…
White Dwarfs in Clathrate Cages!
Now finding this most likely… Still one can dream!
Cometary Hallucinations
Or my cometary daydreaming, Lol Logan!
These new findings really widen the Planetary Science panorama. Fully deserves the party. Sorry about the noise.
Clathrates being the hiders is just my crazy argumentation [and some Others’]. Endorsed Paper doesn’t point to any particular mechanism.
Gerald is referring to genesis of Oxygen at our Mother Nebula. Out of the shock wave gas mixes readily cool [‘seed’ crystallize? :)].
The 02 is hiding NOW inside the cometary material. This is not hallucination. Wake up Ramcomet, you’re daydreaming! 🙂
This ‘cooling’ begs for an explanation form Harvey. Imagining that Is the dust which ‘cools’ and homogenize temperatures at first.
I’d think, we get adiabatic cooling first, then radiative, until stuff is close to (e.g. cosmic) background.
Shell structure of white dwarf may allow local excess of oxygen over hydrogen in the expanding debris cloud of the SN. Slow-down by dense surrounding nebula.
Time for clathrate dust to condense.
Later trapped in comet in the middle or outer parts of the protoplanetary disk, after Jeans-instability and accretion of young (proto-) Sun.
– roughly speaking
Hi Gerald. What’s SN? That slowdown by surrounds is really intriguing [Hadn’t considered it]. Could -beyond a certain distance- have what Harvey describes as a ‘Two Way’ molecular flow?
You suggest clathrate dust precedes condensation. Are those condensates primigenial comet-esimals?
“Later trapped in comet in the middle or outer parts of the protoplanetary disk, after Jeans-instability and accretion of young (proto-) Sun.- roughly speaking”
And this late part doesn’t feel fine [to me]. Thinking about mother sharks. Baby sharks have been feed with babies, which had been feed with babies.
Speculating that could be a lot more evolved cometary material, than simple clathrate condensates. At the proto-planetary disk.
Proto-Star outflow should be highly ionized and hot [not molecular oxygen], Then clathrate dust is accreted NOT inside of the shock wave, but at the immediate outside, as Adele L. Plunkett et al. suggest, by the effecting kinematics.
[We are having a thick layer where hot proto-Star outflow and cold (stationary?) Mother Nebula substance (and particulate) co-exists! 🙂 _]
https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-573967
Think Gerald meant SuperNova by SN, Logan.
Correct, Ramcomet.
Answered this further down, because of temporary technical issues.
haha.
Trying, The bigger the grain of dust, the more complex. Specially if grain is heterogeneous in molecular composition.
Vibrational energy is the first to go. As with everything complex enough, parts highly elastic, and parts highly dampening.
The dampening areas of the dust of grain readily can start to accept impacting gas molecules.
Speculating also a certain deposition order, to the adsorbates’ molecular weight and surface properties, on a time line.
[Maybe not ‘caged’, but molecularly layered. Sounds pretty ‘gripping’]
Not clear how nitrogen abundance is so much lower in spite of oxygen’s higher reactivity. Can we assume that the comet moved to a low-period orbit only over the last few millenia, and the oxygen-protecting mechanism was significantly damaged only during the recent low-period orbits, perhaps during closer perihelia? Can coming close to Jupiter play a role?
Hi Kamal. References are very high level. Maybe misunderstanding, but seems Solar System is quite not yet fully detached from Mother Nebula. Some tide-in and tide-out.
Maybe We just kind of look-up Ducky in this balancing game.
Which could be the mechanics of looking-up from a foreigner mass wave? Is it possible? Sounds hyperbolic to me.
This is cometary fiction.
Oxygen forms more readily in aging stars than nitrogen.
Strange only, that it isn’t bound chemically.
A ‘present’ from a near passing brown Star? Creating a gravitational ‘channel’? Locked-up by Jupiter?
‘Sipped in’ by Jupiter?
“…and the oxygen-protecting mechanism was significantly damaged”.
The ‘oxygen-protecting mechanism’ is not damaged, Primordial oxygen is actually still ‘caged’ inside the cometary material.
The ‘mechanism’ is being ‘deconstructed’ as cometary material sublimation occurs.
I gave a talk on comets today for amateur astronomers. A couple of wild questions which came up.
First question: earlier the deuterium-hydrogen ratio was pointed out as not matching Earth’s H2O. Do the new O2 results impinge on this data? Second question: even if Earth’s water did not come from 67P-type comets, is it plausible that Earth’s oxygen initially came from this kind of comets?
Kamal,
out-of-the-hip, regarding oxygen:
Most of the oxygen on Earth was probably bound to silicates.
Oxygen in the air is only a tiny fraction of the total oxygen.
Since the formation of Earth, oxygen of Earth’s crust, including oceans and atmosphere, went through several cycles. Therefore it’s (close to) impossible to identify the oxygen added by comets.
Small zircon crystals might have survived unaltered since the formation of Earth. That’s – besides meteorites – the only (bound) oxygen on Earth, I’m aware of, that may be tracked back to the origins of our solar system.
The ratio of contributions by asteroids and comets to the water on Earth is unknown, as far as I know.
67P is (almost) primordial; that’s why it is visited by Rosetta. A piece of the puzzle hardly found on Earth.
@Gerald
“Most of the oxygen on Earth was probably bound to silicates.
Oxygen in the air is only a tiny fraction of the total oxygen.”
Indeed! just as on 67P which, like asteroids, is clearly also made up mainly of silicates…
“And thus, even though it must have been incorporated into the comet during its formation, this is not so easily explained by current Solar System formation models.”
Referring to the unexpectedly high abundance of molecular oxygen detected near the nucleus. In other words it does not conform to the hypothetical solar system formation model and primordial origin of comets but we will run with that hypothesis anyway in our interpretation.
So alternatively I am going to attempt to interpret the results using the surface combustion of hydrocarbons hypothesis, and leave aside the question of comet origin.
The combustion hypothesis requires incident highly energetic solar wind protons to release oxygen from the nucleus rock ( radiolysis) which reacts with the nucleus surface hydrocarbons producing H2O and CO2 with completion, and interestingly also O2 since an oxygen surplus is usually synonymous with compete combustion. If the reaction is incomplete CO and carbon would appear in addition in the products, resulting from an oxygen deficit at the reaction site. Oxygen may or may not be reduced in a particular sample depending on its persistence. The surface reactions are likely to be constantly changing and contributing to an accumulation of products in the coma, measured at any one time.
“The amount of molecular oxygen detected showed a strong relationship to the amount of water measured at any given time, suggesting that their origin on the nucleus and release mechanism are linked.”
The amount of oxygen produced would be expected to be directly proportional to the integrated energy of the proton flux. This would correlate with the maximum intensity of combustion reaction and the maximum water volume. However as the proton flux and energy appears to be unmeasured it is impossible to make this correlation.
“By contrast, the amount of O2 seen was poorly correlated with carbon monoxide and molecular nitrogen, even though they have a similar volatility to O2.”
Presumably this means directly proportional hence the comment about similar volatility. The amount of oxygen would be expected to correlate inversely with CO, allowing however for the distortion created by accumulation and persistence
“In more detail, the O2/H2O ratio was seen to decrease for high H2O abundances, ”
As more of the available oxygen was consumed the less likely it would be to appear as surplus in the products and the greater the water volume expected would be.
“by first considering photolysis and radiolysis of water ice ”
The investigators looked at the possibility of radiolysis but only of ice, even though evidence has yet to be produced that the nucleus consists of ice. The isolated patches of surface ice identified spectroscopically could not account for the emitted water volumes.
They then go on to dismiss ice radiolysis, even though it could have built up surface oxygen to a few metres of depth in a hypothetical billions of years sojourn in the Kuiper belt, as the oxygen layer would have been consumed during a later period ( more billions of years) in the solar system. And recent radiolysis as an oxygen source is ruled out as it would only have affected the top few micrometres of surface, this statement apparently made without knowledge of the proton flux or energy. Then a dismissal of this micrometric layer as a source
“But if this was the primary source of the O2 then we would have expected to see a decrease in the O2/H2O ratio as this layer was removed during the six-month timespan of our observations,”
as though the proton radiolysis would have been a transitory event.
And no radiolysis of anything else considered even though the comet emission is known to be 80 % dust and 20 % water.
The investigators then go on to consider ways in which oxygen could have been accumulated on or in the comet during its primordial development and carried to the present day and released. Had this been the case of course there would be no requirement for an energetic proton flux to continuously release oxygen from the nucleus rock to establish the combustion reaction at the surface. The oxygen would already be free and available . All that would be required would be a small one off input of activation energy and the reaction would proceed on its exothermic way throughout the whole orbit until either the oxygen or the fuel was consumed. We do not see this behaviour from comets so it is unlikely that free oxygen is available.
In any event the authors observe that
“Regardless of how it was made, the O2 was also somehow protected during the accretion stage of the comet: this must have happened gently to avoid the O2 being destroyed by further chemical reactions,”
They are happy with this despite the truth of this statement early in the blog
“Oxygen is the third most abundant element in the Universe, but the simplest molecular version of the gas, O2, has proven surprisingly hard to track down, even in star-forming clouds, because it is highly reactive and readily breaks apart to bind with other atoms and molecules.”
In other words it would be extremely unlikely that it could accumulate and survive over billions of years.
Much more likely that it would be produced and consumed relatively quickly.
So an interesting set of results speculatively interpreted. The primordial accumulation source is however far from the most likely and impossible to verify.
The combustion source could be confirmed by simple temperature measurement of the jets.
Had forgot OriginalJohn. Now you have your plenty of Oxygen and Fuels. Just need Pressure and a constant supply of Sparks. Curious how ideas are evolving too 🙂
… and we get a mini-nova …
Not a constant supply of sparks Logan. Just enough to supply the activtion energy then the reaction keeps going on its own. It is strongly exothermic. The same as your fire keeps going if you supply the activation energy with a match and some kindling.
By pressure I presume you mean the impact of incident protons and yes indeed as yet we have no published figure for that. There is though good reason to believe the “pressure” would be adequately achieved from the effect of natural plasma behaviour within the solar wind.
Proton energy density at he nucleus surface awaited.
@OJ
There is just so much wrong with that that I’m not even sure where to start!
Combustion? How does that happen on a comet? Nonsense.
As has also been said, ad nauseam, the solar wind is nowhere near dense enough to account for the outgassing of any species seen on comets. And yes, it has been measured, and is continually monitored, both in Earth orbit, and at 67P.
“They then go on to dismiss ice radiolysis, even though it could have built up surface oxygen to a few metres of depth…”
Again, that is nonsense. As the article says, the deepest that SW ions can penetrate is a few microns (millionths of a metre)! It would have to somehow replace all the O2 and H2O within the few years when the comet was at distances precluding sublimation. Once that starts, poof! it’s gone, like the authors say. To account for the H2O and the O2, you need a subsurface reservoir. This has been seen and/ or strongly inferred from the findings of solid ice grains in the ejecta at Tempel 1, the grains within the jets at Hartley 2 and, seemingly (based on the 2015 AGU abstracts) by MIRO at this comet.
“The combustion source could be confirmed by simple temperature measurement of the jets.”
You mean like the CO2 jets at 103P Hartley 2? The ones that were so hot that they were entraining water ice grains over the period of the measurements? And whose source regions were rather cold?
Pure pseudoscience.
ianw16 says:
“@OJ: There is just so much wrong with that that I’m not even sure where to start!”
Might I suggest that you *start* by giving your personal explanation of this observation of abundant water-related oxygen emanating from 67P. Apparently, the mission leaders, who themselves remained “in denial” (I quote Kathrin Altwegg) for several months before finally publishing their paradigm-shattering findings, might need your help.
You apparently haven’t yet come terms with the fact that, according to the experts themselves, all current “consensus” (!) models of the formation of the solar system (and hence, presumably, of all other star systems) have just been blown away at a stroke. Back to the drawing board, Ian. Don’t resign yourself to just being like one of the orchestra which bravely continued to play as the Titanic sank…
Ian, you would be more convincing if you replaced your oft-repeated “nonsense” judgment by something a little more objective (but it’s true that you do no better and no worse than the “rubbish” judgment preferred by other regular mainstream contributors…). With our more universal culture, citizen scientists like myself expect a slightly higher standard of argument, to address the big picture which your respectable but necessarily narrow specialist training has apparently blinded you to. It’s a classic case of not being able to see the wood for the trees.
We would like to know in particular what new “accretion” (or other) model you propose which might reconcile the newly-emerged, contradictory, assumptions of the simultaneous “suddenness” and “gentleness” of cometary formation required by these brand-new oxygen findings with the demonstrated role of extremely high temperatures, required by the formation of the olivine found in the dust samples acquired by the Stardust mission to comet Wild 2 in 2004.
When you say wrong ian what it really means is outside your understanding or outside your beliefs. There is nothing actually wrong with the surface combustion hypothesis. It is fully plausible and to be effective requires only the necessary energy density of protons. No figures available for proton energy density in the coma so no way of knowing if the conditions are there or not.
Similarly your concept of nonsense is a subjective expression of outside your comprehension.
“Combustion. How does it happen on a comet”
Well, how it happens ian is that when there is sufficient oxygen available and there is hydrocarbon fuel available all that is required is a small activation energy input ( as in lighting a fire) then the reaction proceeds exothermically until either the oxygen or the fuel is exhausted. The activation energy is provided by the proton flux.
No nonsense there ian. Basic combustion science.
And if it is said ad nauseam that it is not possible then it is misunderstood ad nauseam.
The assertion that oxygen could have built up to a few metres of depth was from the authors of the report, not me. Their nonsense then. And your ad nauseam assumptions about possible depths of penetration and rates of reaction require a knowledge of the proton energy density which you don’t have. So they are subjective guesses and no basis for an argument, certainly not an argument of nonsense. They are nonsense in themselves.
To account for H2O and CO2 you need a source. It could be a sub surface reservoir or it could be a surface combustion reaction. No way of knowing which, although no subsurface reservoir has been identified so that one is rather weak. Certainly the presence of ice grains in the discharge is no evidence of anything subsurface when there are other ways ice could form, which there are.
You have a strong tendency ian to be convinced by one spurious argument at the expense of all the rest. This does not help your process of judgement.
And no, I don’t mean like the CO2 jets at Hartley 2, a rapid flyby mission with low spatial resolution of data. I mean the jets emitted at varying levels of intensity which we have all been observing in the 67P images for months with the Rosetta craft in situ. Yet the opportunity of making detailed and prolonged temperature measurement of the jets, that would tell us a great deal, appears to have been passed up. No data at all so far in over a year. Just the ad nauseam assumption that the jets are cold sublimated gas, which could also be verified by temperature measurements.
As for pseudoscience ian it appears that your definition of that is also rather subjective. In reality presenting an assumption as fact and having it underly all interpretations of subsequent results is pseudoscience. Picking a preferred interpretation at the expense of equally or more plausible others is pseudo science. Presenting a result as proving something when in reality it proves nothing is pseudoscience. What is quite definitely not pseudo science is proposing a scientifically plausible hypothesis and calling for the release of data which could confirm or refute it from the only possible source of that data.
Neither is it pseudoscience to objectively criticise a piece of published work full of subjective errors. In fact it would be pseudoscience to let it go or pretend it was alright.
As has been pointed out on *numerous* occasions, this hypothesis bears no resemblance to real physics & chemistry whatever.
Even if we took the ‘raw’ solar wind, its penetration depth into the organic layer is extremely shallow; the energy will be dumped in that layer.
If it does penetrate to a silicate/hydrocarbon interface, – & we have seen even less silicate than water – only the few eV deposited close to the interface could realistically contribute to reactions, and the products are very likely to remain bound in the matrix in most cases.
There is no obvious mechanism to produce molecular O2 this way.
There are no ‘exothermic self sustaining’ silicate/hydrocarbon reactions, as previously claimed & quietly forgotten..
Numerically, each solar proton would need to produce a *VAST* amount of water, CO2 etc *FAR* in excess of the ratio of the (raw) proton energy to the bond-breaking energy.
It does not bear a moments inspection.
@ Harvey
“As has been pointed out on *numerous* occasions, this hypothesis bears no resemblance to real physics & chemistry whatever.”
With all due respect, Harvey, the problem with your “real physics & chemistry” is that they have once more just been shown to be doing an extremely poor job of attempting to predict or even simply explain the observed characteristics of comets. After spectacularly failing to predict or even merely explain 67P’s most obviously anomalous physical features such as its shape, appearance, colour, albedo, stratification, average surface temperature, behaviour or behaviour mechanisms (to mention just a few…), your “real physics & chemistry” can now apparently only just start to account for the finding of very abundant molecular oxygen pouring off 67P by consigning all the existing models of cometary and solar system formation to the wastebin. On the subject of 67P’s abundant oxygen production, André Bieler is recorded as specifically stating that “all the models say it shouldn’t be there and it shouldn’t survive for such a long time”. This is hardly the stuff that *real* science is made of, able to inspire trust in your “real physics & chemistry”, whereby mainstream astrophysicists claim to be able to describe the Universe and its origins down to the original iota… In case you hadn’t noticed, they’ve just been proven wrong, again, by the observational evidence. The application of correct scientific method would thus require the falsification of the standard model to be finally acknowledged and the serious consideration of alternative models having far more accurate descriptive and predictive powers to at last begin.
In actual fact, the establishment description of the Universe has, above all, somehow been entrusted for over a century now, NOT to your “real physics & chemistry”, but to *pure mathematics* which somehow managed to usurp the rightful place of the natural sciences you invoke, and thereby embarrassingly saddle us with the never-observed, unfalsifiable, physically and chemically impossible intellectual constructs known as “The Big Bang”, “inflation”, “black holes”, “dark matter”, “dark energy”, “neutron stars”, “pulsars” and many others. You are perfectly entitled to be happy with this state of affairs but please don’t call it *real* science. The whole, huge, ramshackle card-house is arguably nothing more than science -fiction, and the reality-check represented by the larger-than-life, in situ laboratory of 67P is empirically showing it up as such. With all due respect again Harvey, consideration of the bigger picture shows that your peremptory “It does not bear a moment’s inspection” judgment on the model proposed by Originaljohn stems from the necessarily parochial viewpoint of the director of an Earth-bound laboratory which is understandably unable to replicate the electromagnetic pinching effect focused on 67P and all other comets as they travel through the currents of electrically charged particles commonly and misleadingly known as the solar “wind”. It is the empirical evidence being provided by the 67P laboratory-in-the-sky (for the moment, abundant H2O-producing oxygen, but in the months to come, the upcoming sky-high temperatures and frenetic plasma activity of the so-called “jets”) which will finally re-establish the preeminence of the natural sciences and correct scientific method. Phrased differently, you seem to believe that the output of natural laboratories such as 67P which is currently providing us with outstanding raw data to be analyzed should somehow still be subordinated to the necessarily programmed results obtained by Earth-bound laboratories such as your own. I humbly beg to differ and maintain the opposite to be true.
The total aptness of the name “Rosetta” chosen for this mission is becoming increasingly and ironically apparent with every new disclosure, but certainly not for the reasons originally imagined…
The hiders have to be on the same league [light molecules also] as to make well ‘sealed’ cages.
Ice XVI? IceXVII?
i apteciate ALL OF YOUR AWSOME coments; Thank-You!!
“Science has a universal reach. A scientific discovery about the character of the universe should be one that notional scientists in far-off galaxies could share. The physical laws at least of our own universe remain constant and are intelligible anywhere in it.”
“… It is above all concerned with truth, in effect the ultimate value guiding the practice of science that must be respected by all scientists”
https://nautil.us/issue/29/scaling/why-science-needs-metaphysics
Roger Trigg is the professor emeritus of philosophy at the University of Warwick, and currently the senior research fellow at the Ian Ramsey Centre, University of Oxford…
Not even a single foot out of our little mot of blue dust, but we indeed are ready to share some ultimate values to notional scientists in far-off galaxies.
Being ‘extremism’ a ‘stigmatic’ word in late years, I am going to say only that We Occidentals are extremely ‘exceptional’.
Nowadays, I am a lover of philosophy.
Marco and friends. Humbly asking pardon to you about my impatience.
Hi Emily. Maybe I’m not allowed to talk about Prof. Trigg ideas.
“Excerpted from Beyond Matter by Roger Trigg, published by Templeton Press. Copyright ©2015 by Roger Trigg. All rights reserved.”
“Science can’t tell us whether science explains everything.”
Since Kurt Gödel it can say that it cannot:
https://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_theorems
“…it can say that it cannot” 🙂
Sufficiently complex systems can be used as their own meta-system.
Hence existence of meta-physics not forced by logic.
Systems Theory allow Us to build big houses, of cards.
Leaving aside quantum universe(s), Nature is amazingly non(lineal&unidirectional&mathematically-discrete) AS actual Systems Theory is.
Protocols, proud children of system-atization, where originally intended as a last line of defense against lack of expertize.
Protocols are not, and are not going to be a replacement for expertize.
Organizational structures actively trying to erase expertize from their structure are actually damaging the related disciplines [and themselves].
Protocols able to replace expertize need more expertize than expertize has been needed before attempt to replace expertize.
Therefore replacing expertize by protools on lack of expertize stupid idea, possibly due to lack of expertize.
If leaving to the protocols, a certain sub Captain, We wouldn’t be here, chatting like that 🙂
Wen neural AI ignites, it’s going to be following our directives, quite probably in a protocolary definition. And it’s going to be following its own privative directives, surely in a neural definition! Right into Asimov’s conundrum.
Don’t care, it isn’t following our directives, at least not those we thought it would be our directives.
Quite apart from the devastation effect which this finding of abundant molecular oxygen above the surface of the 67P nucleus is having on the current paradigm not only of how comets, but also the solar system itself formed, I consider the most revealing aspect of this finding to be its implications for how mainstream science is conducted. As Kathrin Altwegg admitted, the team was “in denial” for many long months, so utterly impossible did the finding appear and so totally inconsistent was it with everything that the “consensus” opinion believed about the composition of comet nuclei. As André Bieler admitted, “As soon as we got close enough to the comet, we actually found it right away” . That was way back in September 2014, some fourteen months before the finding was finally disclosed.
Now as I (and others) have already pointed out on several occasions in other threads, there has so far also been a curious absence of data disclosed on the temperature and plasma characteristics of the “jets” (in particular the spectacular outbursts observed during the July 29, August 12 and August 22 events). The only comment made in the blog-post on the “extraordinarily bright” August 22 event was that that the team was “busy analyzing the data to understand the nature of these events”, meaning that the collected data was (and probably still is) literally incomprehensible for them. When the extremely high temperature and the extremely active plasma data are at last published (probably several more months in the future), it will be seen that in that respect too, the team was “in denial”. It may take a very long time, but we will ultimately be told the truth about the real nature of 67P.
I haven’t (yet) seen mention of a simple chemical mechanism consistent with observations:
Slow photolysis of ice at (say) 10-20K to hydroxyl, with trapping of the initial product hydrogen peroxide in the cold matrix. As H2O2 will itself photolyse, there probably wil be an equilibrium concentration (analogous with our ozone production/destruction by solar UV). Long exposure of small ice particles, followed by gentle agglomeration, would give a homogeneous distribution in the final comet.
Thermal release of H2O2 and one of many catalytic surfaces would rapidly generate oxygen in fairly constant proportion to water. 3.8% O2 = 8% H2O2.
If true, comets may contain ~400kJ per kg “ice” – which would make them very interesting objects.
Well Harvey you have laid out your assumptions here reflecting your vision of reality and there is no evidence to support it. Once again I remind you that the combustion reaction is an oxygen/ hydrocarbon reaction and it is strongly exothermic. Once again I remind you that in view of the properties and behaviour of plasma you cannot assume that the proton density and energy is that of the background solar wind. You do not know the energy density of the protons at the nucleus surface so you cannot know anything about depths of penetration or rates of reaction. Your assumptions are your preferences because you wish it to be unfavourable for proton energy release of oxygen and generation of water from combustion. You wish this to support the sublimation of ice hypothesis. You state right or wrong depending on how close it is to your beliefs and assumptions. There is not a shred of objectivity in your approach.
I will reiterate once again that there is more than enough energy in the background level solar wind protons to separate the Si- O bond, hundreds of times the required energy per proton . To satisfy the water production volumes an increase in proton current density is required. Such an increase of several orders of magnitude could readily be achieved by natural plasma behaviour within the solar wind. There is no evidence to refute this because there is as yet no data for proton density within the coma and particularly near the nucleus. To assume it is the same as the background interplanetary level is absurd.
In addition there are natural plasma characteristics that can readily increase the ion energy by many orders of magnitude also, by acceleration in naturally formed electric fields that occur at plasma boundaries. Such an increase in energy is offset against the density requirement, reducing the density increase necessary. You do not know the proton energies within the coma because no data is published. You base your deductions on ignorant assumptions therefore.
Until the proton data within the coma is available there is nothing to refute the proton induced release of oxygen from the nucleus and subsequent oxygen/ hydrocarbon combustion reaction, least of all your absurdly subjective argument.
By the way, I also draw your attention to a recently published ESA figure of 80% dust to 20% water in the jets, which contradicts your released silicate deficit assumption too.
It occurs to me that the discovery of very abundant oxygen pouring off 67P raises another question about how mainstream science works: that of how scientific “discoveries” are documented and interpreted via the system of peer-reviewed articles published in respectable scientific journals. More specifically, which one are we to believe when two peer-reviewed articles published by stakeholders in the same mission within four months of each other present radically different findings and conclusions on the same subject?
In the present case, the May 2015 article “Measurements of the near-nucleus coma of comet 67P/Churyumov-Gerasimenko with the Alice far-ultraviolet spectrograph on Rosetta”, published by Feldman et al. in Astronomy & Astrophysics (https://www.aanda.org/articles/aa/pdf/2015/11/aa25925-15.pdf), found that the oxygen of indeterminate abundance detected close to the surface of the 67P nucleus was the result of “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface”, i.e. by UV photodissociation. This finding is now apparently contradicted by these new findings of abundant oxygen allegedly trapped homogeneously throughout the interior of the comet, published in the paper “Abundant molecular oxygen in the coma of 67P/Churyumov–Gerasimenko,” by A. Bieler et al. published in the 29 October 2015 issue of the journal Nature.
This issue in turn raises a number of questions: Does anyone know which of these two incompatible sets of findings is the right one? Are we supposed to conclude, because their study was published four months earlier, that the Alice team members were mistaken in attributing the oxygen they detected to the rapid breakup of water molecules? Who is the arbitrator in this sort of case? Is there a procedure for withdrawing a peer-reviewed article if its findings are shown to be questionable or plain wrong? Can the Feldman et al. paper still be referred to by subsequent researchers to prove the supposed reality of UV photodissociation of H20 to produce oxygen on comets, even if it is now considered to be obsolete? Why is there not more coordination and communication between the various Rosetta teams before going into print so as to avoid this sort of confusion?
Any answers to any of these questions would be very helpful.
Hi Marco,
I’m answering here, since captcha didn’t work above.
you .. “have suggested thermal conduction(of the sun’s heat) through a thick (non-porous) crust rich with PAHs which are as thermally conductive as metal.”
Abundant PAHs thermally as conductive as metal on the comet are a big assumption. Nevertheless following this assumption, there would be a heat transport from the interior to the outside, resulting in high surface temperature on the night side, and low temperature on the day side, meaning very high thermal inertia. Observed thus far is low thermal inertia. This can only partially be discussed away by the dust cover. A too thick dust cover would prevent solar heat from reaching the surmised thermally conductive layer, and rule out the mechanism you’re suggesting.
So, as far as I see, you either question the observations or you discard your mechanism. Otherwise you run into contradictions, very strange material properties, or you need a naturally occuring efficient Carnot cycle which appears unbased and very unlikely.
https://en.wikipedia.org/wiki/Carnot_cycle
“Radiative heat loss would overwhelm conduction from the warm interior, at the polar night.”
This would be obvious by very high termal inertia, in contrast to measurements.
“I suggest by the pattern of outgassing proportional to water, many of them are dissolved in liquid water (eg. O2)”
Oxygen solves poorly in liquid water, the constant of Henry’s law (https://en.wikipedia.org/wiki/Henry%27s_law) is 769.23 atm/mol (at 298.15K):
https://butane.chem.uiuc.edu/pshapley/GenChem1/L23/web-L23.pdf
Oxygen is more soluble by a factor of 1.722 at the normal pressure freezing point 273.15K.
One mol/liter would be still be only about 1.8%.
So, at 1 bar you would be at least 3 orders of magnitude off the measurements.
See table 3 or figure 7 of this paper for high-pressure solubility:
https://gcmodel.kl-edi.ac.cn/archives/publications/68-GCA-2010-Geng.pdf
Calculated solubility at 1000 bar is about 0.94 mol/kg at 273 K, still less than observed at 67P. Experiments at those pressures are somewhere between mad and impossible, since the oxygen destroys the vessel by oxidation.
Hence high pressure liquid water with relevant dissolved oxygen is ruled out by the presence of reduced material, like hydrocarbons or carbon monoxide.
At high temperatures, say above 450 K, and high pressure, say above 100bar, you get solubilities up to the 10-fold, still factor 100 below observations.
Only solution: low temperatures, either as clathrate hydrate, available data indicate improved stabiity on low temperature:
https://www.researchgate.net/publication/50253877_Ice-Clathrate_Hydrate-Gas_Phase_Equilibria_for_Air_Oxygen_Nitrogen_Carbon_Monoxide_Methane_or_Ethane__Water_System
Or oxygen ice, stable at very low temperatures.
Basics about clathrates:
https://ps.uci.edu/scholar/sites/default/files/understanding_a_clathrate_hydrate_2010_1.pdf
Gerald and Marco,
Ha! Have been waiting for a chance to share this compleeeeeeeetely “outside the box” video, seemingly unpredictably strange result of conductive heat and/or as Gerald says, …”very strange materials.”!
https://scienceplx.com/watch-what-a-red-hot-nickel-ball-does-to-floral-foam
While that nickel ball is one hot dense …, I can’t believe the total saturation extent of the conductive heat. Or is that… Dare I say it? A kind of smoldering combustion? No, not suggesting EU here!
If nothing else, a real visual eye opener underscoring the folly of us trying to relate our earthly experiences to super strange physical processes on comets, Pluto and Charon, other bizarre objects, strange materials and extreme temperatures of outer space!
Thought you would find interesting in a few ways to stir the old nuerons…
This is Cometary Daydreaming.
While awake, Logan 😉
Blog’s rules doesn’t allow me to say what I think of this video, Ram 🙂
Humbly accepting I do know nothing of foam/aero-gel/etc physics and chemistry. Imprinted on my mind for rest of life.
Heat transfer (and combustion) in that video 🙂 as you have brought the demonstration up to the table. While keeping a certain structural resilience.
[The heat waves, Harvey, Gerald]
That Team bringing science to the world [in this impacting, digestible form] have all my respect.
Fire forensics should study this in detail.
The video is fascinating. It does appear to be a form of smouldering combustion, right near the end you see some red glow internally.
However combustion gives up at low pressures, for the reasons posted elsewhere. For an H2/O2 mix, about as inflammable as you can get, NO mixture will ignite below about 54Pa. The reasons are straightforwardly due to conservation of energy and momentum in collisions.
It’s more difficult for a solid/gas reaction, but again undoubtedly it will become more difficult, then cease as pressure falls.
Harvey is right. You have to ask the Team to replay the experiment on an air depleted acrylic|polycarbonate chamber [industrial, not necessarily lab vacuum]! Ramcomet 🙂
They will have a down, gas and ashes clogging flow, and also will stand to the test. My speculation.
Hi Logan,
regarding post https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-574366:
SN = supernova
Type Ia supernova forms by addition of surrounding material, usually provided by an expanding red giant companion.
These giants tend to eject parts of their hull, later serving as “brake” for type Ia supernova remnant.
Mean density of younger universe was higher than today, and galaxies had less collisions cleaning them from clouds, so presence of cloud more likely for stars.
Hi Gerald. Can’t make an image of a denser, less collisional visible Universe.
… Regarding baby sharks: Cloud needs to be sufficiently dense. That’s a little more likely in a collapsing cloud (Jeans instability), and much more likely in the protosolar or protoplanetary disk.
Dust is well-known from interstellar clouds.
Cometesimals would be interesting. I’m not aware of evidence but observation is difficult, not easiy ruled out.
Although minimum grain size is needed for clathrates to condense on them, see
“Planetary and Interstellar Processes Relevant to the Origins of Life”
https://books.google.de/books?id=qTL0CAAAQBAJ&printsec=frontcover&hl=de#v=onepage&q&f=false
page 42ff.
… regarding your post https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-574392
Yes, of course. supernova remnants take time to cool down.
Hi Gerald. Thanks for answering, accepting your arguments and carrying back ‘mid age and late’ states of accretion to [outskirts of] big gravitational centers [populating the inside of collapsing (or impacted) Nebulas].
[Not yet discarding turbulent surfaces at inner, profound, sloow, long term ‘currents’ within Nebulas, as nurseries of something more than cometary dust and primigenial comet-esimals].
Humboldt name could appear in the future, inside our children’s space books 🙂
Re systems theory (of Logan’s post https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-574340)
I’ve been thinking e.g. of the foundations of mathematics, instead:
https://en.wikipedia.org/wiki/Metamathematics
Metamathematics can be seen as part of mathematics.
Hence a sufficiently complex mathematical description of physics is sufficiently powerful to contain a mathematical description of metaphysics.
This would make / makes metaphysics isomorphic to (hence undiscernible from) a sub-discipline of physics.
“Sufficiently powerful” can e.g. mean: containing arithmetics.
Mathematics (not necessarily mathematicians) is sufficiently powerful to describe any self-consistent finite or infinite physics.
Hence we get a physics isomorphic to (hence undistinguishable from) an (unknown, and possibly partially inaccessible) mathematical theory (at least in the most general sense).
A baby example is our ability to think about the universe on a meta-level, although we are part of the universe.
Our finity limits our understanding.
An infinite universe doesn’t necessarily need to obey these limitations.
“…Mathematics (not necessarily mathematicians)…”
Think you have kind of a Gordian Knot there, Gerald 🙂
“…Metamathematics can be seen as part of mathematics.”
?? !!!!
“An infinite universe doesn’t necessarily need to obey these limitations”.
Nature obeys nothing. ‘Laws’ are human and just for human minds to obey.
Unfortunately that ancient word have been ‘imported’ so long ago.
“Renaissance Men” trying to explain -in few, easy words- concepts of probability.
Worse yet, that probability forcedly delimited by the ‘Law’ issuer perspective, and experimental design.
As we polish models of Nature, is our own mind which is ‘obeying’, by changing perception and behavior.
“Vulcan had every right to exist. In Newton’s universe it had an obligation to be there. It wasn’t.
The next move was obvious, except no one dared make it: Could Newton [‘Laws’] be wrong?”
Parenthesis is mine. Lovely flash back, on History of Planetary Science.
https://www.theatlantic.com/science/archive/2015/11/science-doesnt-work-the-way-you-think-it-does/414744/
“Thomas Levenson is a professor of science writing at the Massachusetts Institute of Technology. He is the author of The Hunt for Vulcan.”
Also:
https://en.wikipedia.org/wiki/Vulcan_%28hypothetical_planet%29
Sorry to deviate from this thread, but your link, Logan,
https://www.theatlantic.com/science/archive/2015/11/science-doesnt-work-the-way-you-think-it-does/414744/
… needs to be read again and again by the author’s and supporters of the Contact Binary crowd, when not remotely considering aspects of Stretch Hypothesis.
The other side of the fence appears so ‘perfect’… Find it ‘spooky’.
https://phys.org/news/2015-11-derivation-pi-links-quantum-physics.html
Sorry for perhaps stating the obvious, but the combination on one aspect of the molecular oxygen findings and an essential property of oxygen leads in all logic to an inescapable conclusion.
The *finding* is that while the oxygen/water ratio remains more or less constant (except that, according to the blog-post, “the O2/H2O ratio was seen to decrease for high H2O abundances”), the abundance of detected oxygen is inversely proportional to the distance from the nucleus. This is clearly due to oxygen’s essential *property* described in the blog-post: “it is highly reactive and readily breaks apart to bind with other atoms and molecules”. (This, incidentally, is no doubt why hydroxyl or water has been detected by Earth-based telescopes in outer comet comas but absolutely no oxygen: the oxygen has already vanished because it has reacted with other elements…)
The inescapable conclusion is that the oxygen molecules emanating from the surface are indeed very quickly reacting with the most likely (being the most abundant and reactive) element: hydrogen atoms from the solar “wind”, to form hydroxyl and/or water. Anyone who wishes to dispute this logic would need to propose another mechanism to account for the fact that the oxygen which ROSINA finds to be “the fourth most abundant compound in the gaseous coma of 67P after water, carbon monoxide and carbon dioxide” suddenly becomes undetectable, even as a trace element, in the outer coma and tail of comets.
And this is very precisely the chain of events which has always been predicted by the EU model of comets… It’s nice to see confirmation of it coming from an impeccably peer-reviewed mainstream source. Instead of being “over 4.6 billion years old”, the oxygen which is continuously being generated from the nucleus’s silicate oxides by electric discharge machining no doubt actually only “lives” for a matter of mere minutes, seconds or even milliseconds before combining with hydrogen atoms. Rosetta is constantly detecting abundant oxygen, but it is not at all the same oxygen from one minute or second to the next. The supply available to constantly replenish this reservoir of short-lived oxygen is virtually unlimited, since the source of it is the billions of tons of silicates which make up the rock-solid nucleus of all comets (and asteroids)….
Since the hydroxyl/water detected in comet comas is thus seen to be the result of a continuous, large-scale oxygen + hydrogen reaction, there is no longer any reason left whatsoever to go looking for its origin in the sublimation of hypothetical, never-detected sub-surface ice which the nucleus is wrongly assumed be made up of in the standard “dirty snowball” model. The only sublimation going on is that of the hoar-frost which forms from the condensation of ambient water-vapour on night-time surfaces as temperatures drop sharply at “night-fall” and which then logically sublimates every cometary morning as the sun rises. It is as banal a meteorological phenomenon as that constantly observed in many places on Earth as overnight dew gently turns to hoar-frost just before dawn and then gently melts as the sun rises on a fine winter’s morning.
By contrast, the overwhelming majority of the comet’s activity, that which has been observed over the past 15 months in the form of spectacular collimated “jets” and dazzling outbursts, is clearly of a totally different kind, being violent and electrical in nature. It’s a bit like the total and utter difference between terrestrial dew and thunder-storms.
Anything below the dust floating in an early ray of Sun goes beyond personal physical experience.
There is uneasiness on addressing, discomfort on participating in conversations about issues of the Micro, or the Tele, for us regular Citizens.
Have to go to the top of the mountain if wanting to look at the place where I live. Macro is also quotidianly invisible.
“…We get adiabatic cooling first, then radiative, until stuff is close to (e.g. cosmic) background.”
On following Gerald’s path, and thinking of an inverse logarithmic cooling curve, we get get a very small window for minerals accretion.
GIADA Team Alessandra&Marco’s preliminary suggestion about dust origin should be upside down, then.
Small, dense particulate is less evolved than the ‘cryo-burnt’, dry, accretional ‘dandelions’.
Hi Gerald,
Looks to me like the unexpected discovery of O2 is leading to some scrambling for a “saving hypothesis”. As is usual, the catch all is hypothesising some untestable early solar system mechanism that may be contradicted by other plausible “saving hypotheses”
In this case, cold trapping of O2 in water ice is incompatible with how CAI’s mixed in with the cold ices to account for their prolific presence in stardust…
‘Dandelions’ are aggregates of the remaining sun dried ‘skeletons’ of former cometary dust.
That’s why they are so ‘ethereal’ 🙂
This is cometary fiction.
‘Dandelions’ present in ‘showers’ because they get ‘airborne’ only by eventual outbursts, and NOT by continuous sublimation.
retry, capta issue
Origanljohn
What always intrigues me about your posts is you utter certainty that you are right & everyone else wrong. Be it the professional team, published material, the three of four clearly qualified scientists & engineers who chip in here, You have this total certainty that you know better. What ‘quality control’ do you apply to your understanding? How do you test it? It is frequently apparent that you have no understanding at all of the mathematical & numerical aspects, yet you feel able to make ‘ex-cathedra’ statements about what is going on. It seems quite bizarre that you don’t understand the manifest limitations of your own understanding.
Now of course it’s entirely reasonable to ask me the same question. But I’ve passed an awful lot of relevant exams (rather a long time ago it’s true!); indeed *set* an awful lot of relevant exams, & had them & the model answers checked by external examiners, had by scientific performance reviewed time & again annually, for promotion, new jobs. Then there are the membership committees of several ‘learned societies’, the reviewers of my papers, grant applications, final reports. My consultancy customers who pay good money for my solutions to their problems; the Universities that invite me to spend time there. And so on; I’m not trying to boast, just to point out that I don’t have to rely on *my own* opinion of whether I know this stuff or not; I, *like other professional scientists & engineers*, am repeatedly ‘vetted’ to check that I do.
I limit my posts to stuff I know about. I worked with a *wide* variety of discharges for decades (and used to occasionally lunch with von Engel (as he was always known- an elderly gentleman even then) an early doyenne of the field),an elderly gentleman even then ; I’ve sent I don’t know how many samples off for ion implantation & run several related simulation codes routinely; (I *assume* you understand the relevance!) built more vacuum, cryogenic, high temperature & high voltage etc systems than I care to think about; & spectroscopy & ‘the infrared’ has been a forte for decades.
So I have rather a lot of experience, & rather a lot of external ‘quality control’ that says I know what I’m talking about; how do *you* know, with such utter certainty, you are right, & we are all wrong?
Hi Marco,
re your posts
https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-573152
and
https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-574375
(“So, unless I believed the Whipple paradigm to be unquestionable, I believe the various explanations of temporary liquid water to be questionable.”)
I’d recommend to read this paper to resolve the presumed inconsistency:
https://onlinelibrary.wiley.com/doi/10.1111/j.1945-5100.2011.01197.x/pdf
First, the aqueous alteration hasn’t been detected “unequivocally”.
Second, there aqueous alterations, if present at all, are very local (on micrometer-scale, and below).
Third, these presumed aqueous alterations can take place within hours near perihelion, as well as a consequence of meteorite impacts, or over weeks well below 0°C.
High presence of liquid water over more than a few hours summed up over the whole billions of years of the lifetime of the comet is ruled out by the high abundance of fine-grained aqueously unaltered silicates.
This is what I have read:
hydrous silicates and carbonate minerals were found to be absent, suggesting a lack of aqueous processing of the cometary dust;
Most of the minerals detected would not have been altered by liquid water.
The assertion that there could never have been any liquid water is completely disproven.
The notions in the article you linked to smacks to me more as a “saving hypothesis” , ie. That the water could have been temporary to account for the aqueously processed minerals found. Not, as you suggest, that the water could not be long term. Long term water is suggested by some more panspermia minded scientists, with articles that do not contradict the material found.
Originialjohn,
your post
https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-574611
is false from beginning to end.
No Gerald, it’s a real post with real deductions.
Real post, Originaljohn, without real semantics, just meaningless copy pasting of keywords to mimic deduction.
This all brings us back to the highly problematic density figure of 0.4 g/cm3 which is attributed to 67P. It has always been used as the ultimate “Vade retro satana”, joker-in-the-pack to be played against the EU model whenever it questioned standard model orthodoxy. I’d like to take this opportunity to point out that this figure has now necessarily become an equally implausibly low figure for the *standard* model as a direct result of the “abundant oxygen” finding.
The problem for the standard model always was the fact that the putative sub-surface ice had a density, like any solid ice, close to 1 g/cm3 while the bulk density of silicate dust is 3 g/cm3. Depending on the chosen ice/dust mix, we thus arrived at an overall material density raging from 1.4 g/cm3 (for an 80% ice/20% dust ‘dirty snowball’) to 2.6 g/cm3 (for a 20% ice/80% dust ‘icy dustball’). Both being far too high to be compatible with the sacrosanct 0.4 g/cm3 figure, it was therefore necessary to invoke an extremely high level of sub-surface porosity, notwithstanding the uncompromisingly solid, not to say rugged and rocky, external appearance of the nucleus. To my knowledge, no formation mechanism has ever been proposed for this porosity and in any case, the possible size of any sub-surface cavities was severely constrained by the CONSERT findings, which ruled out the presence of significant voids inside the nucleus. Yet according to my calculations, for the 0.4 g/cm3 density figure to be achieved, the requirement would be for the percentage of “void” throughout the nucleus interior to be in the range of 70% in the best-case ‘dirty snowball’ scenario, to a stunning 85% in the worse-case ‘icy dustball’ scenario. Now while this already seemed highly implausible given the absence of any proposed formation mechanism or process to account for it, it has now been shown to be literally impossible in view of the severe constraints imposed on the theory by the hypothesized presence of pristine 4.6-billion-year-old molecular oxygen which the standard model suddenly requires to be spread homogeneously throughout the nucleus. The obvious reason for this is quite simply that, while the creation of the hypothesized 70%+ porosity level must necessarily have involved multiple and active, if mysterious, processes, implying both heat and pressure, the ROSINA boss Kathrin Altwegg is forced to admit that the problems are piling up as regards this precise question:“Regardless of how it was made, the O2 was also *somehow* protected during the accretion stage of the comet: this must have happened gently to avoid the O2 being destroyed by further chemical reactions”. It beggars belief to imagine for one instant that even if vast quantities of molecular oxygen were indeed “somehow” trapped inside the partitioning walls of this mysterious, presumably fragile, honeycomb-like structure, it could have stood up to even a few hours of the spectacular activity which comets are rightly reputed for, let alone throughout the oxygen’s alleged 4.6 billion-year existence which the new wisdom is now being forced to postulate. Houston, we have a mega-problem!
The problematic 0.4 g/cm3 density figure now needs to be addressed seriously. It has for too long simply been brandished like a lucky charm each time the obviously solid, rocky nature of 67P has been pointed out. Since it has now clearly become a logical impossibility and embarrassment even for the standard model, the parameters currently used as the basis for the density calculation and the assumptions they are founded on must now be urgently reappraised so as to take account of the observed physical and chemical properties of 67P. As I point out, even the standard theory now requires this…
An excellent example of the argument from incredulity at work.
You wrote.
“The problem for the standard model always was the fact that the putative sub-surface ice had a density, like any solid ice, close to 1 g/cm3 while the bulk density of silicate dust is 3 g/cm3. Depending on the chosen ice/dust mix, we thus arrived at an overall material density raging from 1.4 g/cm3 (for an 80% ice/20% dust ‘dirty snowball’) to 2.6 g/cm3 (for a 20% ice/80% dust ‘icy dustball’). Both being far too high to be compatible with the sacrosanct 0.4 g/cm3 figure, it was therefore necessary to invoke an extremely high level of sub-surface porosity, notwithstanding the uncompromisingly solid, not to say rugged and rocky, external appearance of the nucleus.”
Where this is so hopelessly wrong is confusing the density of a “solid” rock that might contain porosity with the bulk density of a collection of particles. An “individual” silicate dust particle might have a density of 3.0g/cc but collectively the dust particles are separated by space and the resultant bulk density is much lower than the individual density of each particle.
Since bulk density depends on factors such as compaction and particle size, one doesn’t have to “invoke” nonsense such as sub surface cavities or honeycomb structures.
You wrote,
“To my knowledge, no formation mechanism has ever been proposed for this porosity and in any case, the possible size of any sub-surface cavities was severely constrained by the CONSERT findings, which ruled out the presence of significant voids inside the nucleus. Yet according to my calculations, for the 0.4 g/cm3 density figure to be achieved, the requirement would be for the percentage of “void” throughout the nucleus interior to be in the range of 70% in the best-case ‘dirty snowball’ scenario, to a stunning 85%”
What is so stunning about 85%?
You have Earth based materials such as bentonite where the void percentage is as high as 520%.
Soil composed of loose sand has a void percentage of around 85%.
How ironic that CONSERT has measured the porosity in the range 75-85% and a volumetric dust/ice ratio of 0.4-2.6.
https://www.ncbi.nlm.nih.gov/pubmed/26228153
Solid rock on the other hand has a porosity of ZERO PERCENT.
So much for your insistence the comet is made of solid rock.
You wrote,
“It beggars belief to imagine for one instant that even if vast quantities of molecular oxygen were indeed “somehow” trapped inside the partitioning walls of this mysterious, presumably fragile, honeycomb-like structure, it could have stood up to even a few hours of the spectacular activity which comets are rightly reputed for, let alone throughout the oxygen’s alleged 4.6 billion-year existence which the new wisdom is now being forced to postulate. Houston, we have a mega-problem!”
The argument from incredulity in full force now.
Here on Earth we can measure the isotopic ratio of oxygen in the form of trapped water vapour in loose ice and deep sea core deposits dating back hundreds of millions of years.
No such problem exists.
You wrote,
“The problematic 0.4 g/cm3 density figure now needs to be addressed seriously. It has for too long simply been brandished like a lucky charm each time the obviously solid, rocky nature of 67P has been pointed out. Since it has now clearly become a logical impossibility and embarrassment even for the standard model, the parameters currently used as the basis for the density calculation and the assumptions they are founded on must now be urgently reappraised so as to take account of the observed physical and chemical properties of 67P. As I point out, even the standard theory now requires this…”
The 0.4g/cc is only a problem to you because along with the CONSERT results it contradicts your faith based electric comet.
If you are so adamant this value cannot be right it’s up to you demonstrate why the OSIRIS, NAVCAM and Rosetta orbital data that is used in the calculation is wrong.
Also please explain why the CONSERT data is wrong given the electric comet is made out of solid rock.
Your only form of “evidence” is the delusionary practice of making the comet images fit your personal bias. Comet 67P/C-G is made out of solid rock because it “looks solid” in Rosetta images. I’m sure if you try hard enough you will also see the remnants of advanced civilizations…..
As the resident EU spin doctor, you provide a stream of misinformation and a deliberate distortion of the facts.
Few if only a single CONSERT measurement sjastro because of the lander failure and highly likely because of the sudden change from no signal for most of the traverse to received signal as the line of site became tangential to the surface that the signal was merely skimming across the surface of the nucleus or that porosity existed only in a microlayer just below the surface. Not reliable evidence of bulk porosity at all. Still more reason to think it is solid rock with zero porosity.
What blows your fairy tale out of the water is given that Philae’s landing site had been narrowed down to a very small region of uncertainty, the CONSERT measurements were taken when Rosetta was positioned on the opposite side.
https://adsabs.harvard.edu/abs/2015DPS….4741310L
In other words the signal sent from Rosetta to Philae passed through the comet.
What happened to the comet is made from solid rock when we pick the “right” value of G? Out of favour?
Now it’s because the lander is busted!!!!
“Solid rock with zero porosity” is ruled out by the bulk density.
To put it in a lighthearted nutshell, I propose the following limerick:
There was a young comet named Chury
Whose density caused a furore.
When they cried “point 4!”
We answered “Much more!
Your figure fits Chury too poorly!”
@OJ
Right, okay, so now we are heaping one impossible explanation on top of another.
Firstly, how does the solar wind increase by umpteen orders of magnitude between the spacecraft and the comet, and then decrease again (otherwise it would be detected as it passes Rosetta when it is on the anti-sunward side)? What is the mechanism? It isn’t seen by ACE in Earth orbit, it isn’t seen by Rosetta at very low altitudes, but then, magically, reaches billions of ions per cm^3 when it reaches the surface. How? And yes, all the data has been obtained from within the coma. That is where Rosetta spends all of its time! Some of it from ~10 km. https://www.aanda.org/articles/aa/full_html/2015/11/aa26046-15/aa26046-15.html
https://onlinelibrary.wiley.com/doi/10.1002/2015GL064504/full
Any instances where these densities have been recorded? Well, obviosly not, because any spacecraft in the way of such a flux would be fried. I guess Rosetta keeps getting lucky. Philae seemed to do OK as well, even detecting H2O where it sat, and managing not to get fried by either the SW or combustion.
Not to mention the fact that a number of comets have been studied in x-ray from spaceborne platfoms. Such a huge increase in the solar wind density, and its subsequent interaction with cometary neutrals, would be very obvious. No real need to say that this has never been seen. Must be the SW in stealth mode.
Then, of course, we have the diamagnetic cavity seen at Halley and 67P. No solar wind whatsoever reaching the comets. Still outgassing though. Strange that. Outgassing increases as the solar wind interaction with the nucleus declines, and eventually ceases.
And then there is the sputtering data. If these ludicrous SW fluxes were happening, and breaking the Si-O bonds, then we should see roughly as much Si as O2/ H2O, right? No surprise that we don’t. Roughly 600 Si atoms detected in a 20 s period at peak, compared to many millions of H2O molecules! Also no surprise that the Si is detected in areas where the water production (and therefore O2 production) is lowest, as the areas of highest H2O outgassing would be restricting the Sw access to the surface. And no, the SW ions cannot penetrate to more than a few microns. Most experimental data I’ve seen talk in terms of nanometers, so microns is quite generous. Unless you can link to your claim of meter type depths?
https://www.aanda.org/articles/aa/full_html/2015/11/aa25980-15/aa25980-15.html
As for combustion, that is equally unscientific nonsense. Any instances of that you can provide a link to? Any theory? Experiments?
You’ve also conveniently forgotten this: https://www.nature.com/nature/journal/v525/n7570/abs/nature14869.html
H2O seen in the neck region, intimately mixed with organics, and then subsequently sublimating. All happening at no more than ~210K.
And you simply cannot wave away the Hartley 2, Tempel 1 and 67P temperature data as if they never happened, or were too inaccurate. If they’d had error bars of +/- 1000 C, then maybe; but they didn’t. Outgassing, low temperature = no combustion (even if it were possible).
Then, of course, there were the jets at Hartley 2; CO2 with ice grains entrained. Not very hot, then. Combustion would vapourise any ice immediately. Mind you, according to this EU “hypothesis”, solid ice shouldn’t even have been seen at that comet, or Tempel 1, also strongly inferred around Hyakutake, and apparently detected subsurface at 67P by MIRO:
Tempel 1, DI: https://www.planetary.brown.edu/pdfs/3546.pdf
Tempel 1, XMM-Newton: https://home.strw.leidenuniv.nl/~stuwe/MyPapers/AuAv448pL53y2006.pdf
Hartley 2, DI: https://www.sciencemag.org/content/332/6036/1396.full
Hyakutake: https://www.sciencemag.org/content/277/5326/676.short
67P, MIRO: https://agu.confex.com/agu/fm15/meetingapp.cgi/Paper/85998
In short, it’s just one unevidenced, unrealistic and/ or impossible mechanism heaped upon another (i.e pseudoscience). And all to try to explain away something we already know, and have evidence for; that comets have ice beneath their surfaces, and that it sublimates.
I couldn’t agree less with your interpretations ian. Can’t you see that everything you deduce goes back to the dogma of the Whipple model. It is then compounded by a severe lack of understanding of what is normal behaviour in a plasma. And yes whether you believe it or not it is possible for ion densities and energies to change by orders of magnitude within very small distances, certainly centimetres. You forget that ions exist on a scale measured in nanometres.
And once again you have no evidence that the nucleus is composed of ice, beyond a bit of surface frost.
No evidence either as yet of the temperature of the jets of this comet or their ion content. And by jets I mean within 5 kilometres of the nucleus surface at the most, preferably nearer.
When this mission cost a billion why do you keep referring back to other far less capable missions for your argument. The Rosetta results would trump everything, when available.
No evidence either that the lander has survived undamaged, just hope, my hope also.
As far as possible depth of penetration of incident protons goes, think about it. It is a continuous flux so if the depth were microns in a microsecond, that is just one layer. The next layer in the flux then removes the next layer in the rock and so on. And with a background proton speed and density even of around 500 km/sec and 1-10 per cubic cm that is a lot of layers of proton flux, continuously smashing into the freshly exposed surface. The result in one orbit probably will be nucleus material removed in some areas to depths of metres at realistic current densities.
Finally how does the figure you quote of low silicon to water ratio fit in with the recently stated by the ESA ratio in the jets of 80% dust/ 20% water. What is the dust if it is not mainly silicon, ie rock dust.
The sputtering efficiency of protons of this energy on say SiO2 is in the low percent range. Exactly what target you use doesn’t change things much.
Of course there is silicon in compounds in the dust.
That does not resolve the issue that there should be *atomic* silicon sputtered off at well as atomic oxygen, and it’s not seen.
The whole process is umpteen orders of magnitude too weak.
Download the free SRIM/TRIM software and run it, it’s not difficult and quite intuitive to use.
Can’t get any of the reply links to work, so this is for Gerald’s 5/11/15 14:22 post:
Now Gerald, the lottery can pretty accurately determine what the odds of winning are to the millionth (which oddly enough, even though it’s very very very unlikely that any one individual would win, people around the world win lotteries every day, so the likelihood of somone somewhere winning on any given day is actually very very very high), how exactly do you or anyone else accurately determine something like the possibility of active microbes on P67 to some millionth of a chance? Trying to apply some form of statistical math in this case, though scientific sounding, is nonsense. And how long a list of possible explanations could there really be? Not all that long I suppose. And how hard is it to at least keep an open and nonjudgmental mind to those possibilities for at least awhile as more data is gathered. I guess based on your response, exceedingly. Anyway, I myself would be very dubious of life being on a comet (though I’m still rooting for a colony of mole people hitching a ride in there – they have to come from somewhere, right?), but I would not rule it out off hand. And aren’t there any ESA scientists that are experts in this area that could weight in? Anyway, I guess I’m still a bit taken aback at how quickly you, other posters, and the ESA scientists publishing papers seem to rush to judgment and decisive positions (and counter positions) based on little actual data, and claim the scientific high ground while utilizing rather questionable scientific processes and methodology. Many indications of systemic and institutionally rigid and confined thinking patterns (that really have nothing to do with being “scientific) resting upon a huge bedrock of widely agreed upon assumptions that are not recognized as such.
Hi Gerald,
A mini Nova would explain an outburst such as comet Holmes.
Hi Gerald,
Replying here due to Captcha.
You have covered a lot of ground, and there is a great gap between my interpretation of the evidence and the generally accepted interpretation. With regards to the solubility of Oxygen in water, I couldn’t easily find it for the temperatures and pressures I was guessing for inside the pressurised comet (say 20′ C and 20 mBar) . You made your point with the ridiculously high pressures etc. still being inadequate if just from dissolved gases.
However, given I am already postulating a pressurised interior, which is mostly empty space, due to the density, the gases, rather than being dissolved due to not being soluble enough are an internal atmosphere in the pressurised interior being the source of the Oxygen. Proportional to the amount of water because the internal atmosphere is being pushed out roughly in proportional quantities as the water boils off on the edge of the crust pores. I am not questioning any observations, and I am not discarding my mechanism.
There are a lot of assumptions when the thermal inertia is calculated, including the assumption that heat is being lost at the surface due to sublimation. I don’t think the day/ night differential in temperature can tell us much without knowing the thermal transport and cycle…
THOMAS,
“…the abundance of detected oxygen is inversely proportional to the distance from the nucleus. This is clearly due to oxygen’s essential *property* described in the blog-post: ‘it is highly reactive and readily breaks apart to bind with other atoms and molecules’…”
is a major glitch in your conclusions.
Just an inverse square rule for a gas, expanding with a constant velocity, needs to be applied.
Your subsequent conclusions are hence unbased.
High porosity is a straightforward consequence of rough grains accreting in micro-gravity.
Sovereign Slave,
thanks for the good reply
“Now Gerald, the lottery can pretty accurately determine what the odds of winning are to the millionth (which oddly enough, even though it’s very very very unlikely that any one individual would win, people around the world win lotteries every day, so the likelihood of somone somewhere winning on any given day is actually very very very high)”.
I’ve been expecting it. The point is: A million experiments is a different kind of experiment than a single experiment.
The probability for finding liquid water or even life in at least one of a million of randomly chosen samples in our solar system is much higher than finding liquid water or even life on one randomly chosen comet.
I wouldn’t buy a house, and rely on winning the million in a lottery next week.
But I would rely on the lottery company making the million with those who hope to make the million.
Regarding accuracy of the probability: That isn’t necessary as long as you can estimate it to below one in three millions.
And usually you don’t need to go that far, when there are a few clear and obvious options, and there is a consensus among all relevant experts, that certain other options are hopelessly unlikely.
Then you make a decision among the reasonable options and take a tiny risk to be wrong.
When taking a taxi, I’m preferring drivers who stay on the obvious road, instead of spontaneously driving straight down the next-best slope, just because there might be an exceedingly small chance, that the apparent road could be a hologram, and the true, but invisible road makes a curve.
“But there exist holograms” is a bad excuse.
Exobiology is a field of interest for ESA and NASA. But it’s well-known, that it’s like searching a needle in a haystack.
And there are planetary protection protocols to protect celestial bodies from contamination from Earth, whenever there is any non-negligible chance of extinct or extant life there.
Comets are classified as category II
(“Bodies of “significant interest relative to the process of chemical evolution and the origin of life, but where there is only a remote chance that contamination carried by a spacecraft could compromise future investigations.””)
https://planetaryprotection.nasa.gov/categories
Re ianw16
Ian it’s always good to read your articles full of facts as to why not , it would be much more interesting to sometimes hear from you the how!
It would be interesting to see what you make of it all. There are plenty of people on the blog doing it, their comments are as interesting as yours, right or wrong.
What do you make of the free oygen for instance, ok not much to go on but how did it get there how did it stay there and how is it released?
@Thomas
“The problematic 0.4 g/cm3 density figure now needs to be addressed seriously.”
Why? Comets are quite obviously icy, as has been pointed out elsewhere. You want to rewrite gravity theory, just to accommodate this unevidenced electric comet nonsense? How is Rosetta managing to orbit in various configurations, over 15 months, if this density, and therefore gravity, was wrong?
Why did it measure the density at two asteroids and find them to be consistent with rock, but 67P is suddenly different?
Time to remind ourselves that 15 months ago, as Rosetta caught up with 67P, the EU idea of comets was unevidenced pseudoscience, with nothing to back it up. 15 months on, it is still unevidenced pseudoscience with nothing to back it up.
Unless we’ve missed something?
At @SS
“Many indications of systemic and institutionally rigid and confined thinking patterns (that really have nothing to do with being “scientific) resting upon a huge bedrock of widely agreed upon assumptions that are not recognized as such.”
Examples? Specifically to do with comets, seeing as that’s what we’re discussing here. Like to give an example of something that was claimed as “true”, despite being only a possibility?
I think you are confusing *real* science with EU pseudoscience. They are the ones that are getting confused between reality and delusion. Umpteen examples of that.
Anything else? How come *real* scientists have to go through the tortuous process of submitting a paper, getting it past the editor, getting it peer reviewed, and then, finally, getting it published?
Care to tell me how many woo merchants go through that procedure? And why not?
@ianw16,
you may be on thin ice with psuedo science if you excuse the pun, the blog is full of it.
Even the mission itself has exposed some of it.
– dirty snowball
-Comets seeded water on earth (well not this one)
-Comets were forrmed by acretion 4.9 million years ago from a dust cloud (well with the free O2 find the jury is out on this one as well)
There are many more from all sides, but it does make for a lively debate.
regards
Originaljohn’s “hypothesis” (or the more appropriate term article of faith) has been debunked in the comments section using chemical kinetics and thermodynamics.
https://blogs.esa.int/rosetta/2015/09/23/rosetta-reveals-comets-water-ice-cycle/.
Unfortunately originaljohn doesn’t understand the science and another way of pointing out the failure of his hypothesis is to put it to the test.
Whereas originnaljohn has to pretend the comet is made out of rock in order for his hypothesis to have some traction, we can use the Moon instead.
We know
(1) The Moon is made out of rock no pretending is necessary.
(2) Has silicates.
(3) Has a weak magnetic field and is therefore subjected to surface bombardment by the solar wind.
Since O is depleted in originaljohn’s mechanism it is a simple case of measuring the O/Si ratio in sample moon rocks and comparing it to Earth silicate rocks where there is no depletion of O.
The facts are that moon silicate rocks are typical pyroxenes, olivines, feldspars etc and are no different from their Earth counterparts. No depletion occurs.
The other point is the presence of water on the Moon in permanent shadow areas. Originaljohn’s hypothesis would require it to rain on the moon since water is not formed in situ.
Water is formed in situ due to the action of protons in the solar wind on oxygen bonded to the rocks despite the high proton energies.
As explained in the comments section, one needs to understand the chemical kinetics and thermodynamics as to why this mechanism occurs instead of protons shattering Si-O bonds.
As far as 67P/C-G is concerned, even if one assumes originaljohn’s hypothesis was possible, he seems to have missed an obvious point.
How does he explain this combustion or “discharge” activity given the presence of a diamagnetic cavity which prevents the solar wind from colliding into the comet nucleus in the first place?
In fact you have an absurd scenario where this effect should be observed only when the comet is nowhere near perihelion when there is no diamagnetic cavity.
In his model these “combustion” jets should disappear as the comet approaches perihelion which is the very opposite to observation.
After falling off my chair with the free oxygen revelation and its possible implications for solar system evolution, a week or so ago, I was also surprised on Monday by an artical by Nasa (Jim Green diecrtor of planetory ervices)and their Pluto mission.
Paraphrasing, they say due to the lack of small crators across Pluto and Charon it indicates that their may be less small objects in the Kuiper belt than predicted
This leads to doubt about the long standing model of the Kuiper belt that the objects were formed by accumalating small objects ( less than a mile wide).
This supports other models, that the kuiper belt objects 10 miles across may have directly formed
In fact, evidence is that many Kuiper belt objects could of been ”born large” – 40 to 50 kilometer wide.
No mention of how though.
With the surprises on 67p ref the O2 how did it get there, how did it stay their, what was the bith process of the comet etc, its perhaps not that surprising that in another region of space we have some other challenges to belief of long held models?
Dave,
Please check out all the recent articles in NASA’s New Horizons site. The photos and findings there ofPluto and Charon show lack of craters in most areas, but a lot in small areas. And that they both are incredibly, amazingly, dynamic geologically!
Charon and Pluto are being resurfaced by cryovolcanism and occasional mass melting or flooding.
So, pease don’t build anything upon, “…indicates that (there) may be less small objects in the Kuiper Belt than predicted”, at least using Pluto and Charon.
Thanks! 🙂
Logan: “Small, dense particulate is less evolved than the ‘cryo-burnt’, dry, accretional ‘dandelions’.”
https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-575386
This is deep and profound thought.
Are you sure, you’re not a scientist?
[Dropping the mop] Sure about not, Gerald 😉
Average technician here. Most of my discourse and lexicon belong to Teams, Out-Reach and ESA Blog’s Parishioners.
Love for natural sciences, Science of the Planets occupying a special place at hart.
Got to download some of the last ‘bunch’ of Endorsed Papers, before them going beyond a subscription wall 🙂
According to table 3, on page 260 of this paper
ftp://ftp.astro.princeton.edu/draine/papers/pdf/ARAA_41_241.pdf
large grains are e.g. attributed to supernovae, but also to asymptotic giant branch stars.
This paper
https://arxiv.org/pdf/1304.0763v1.pdf
assesses oxygen near supernovae of type Ia-CSM (my first ad-hoc preference) as ambiguous, with oxygen more clearly identified for supernovae of type IIn.
The paper
“Explaining the Galactic Interstellar Dust Grain Size Distribution Function”,
E. Casuso and J.E. Beckman, (direct link didn’t work)
supports your suggestion of a population of primordial large grains:
“Moreover, the effective destruction of grains in supernova remnants affects only the grains of lower sizes…”
Reading comprehension a 30%
[page8] “…it is possible that part of the very broad emission feature around 7400 A ̊ is produced by O I λ7774 blended with [O II] λλ7319, 7330, along with the almost certain [Ca II] λλ7291, 7324.
Moreover, note that the broad emission just blueward of Hα often seen in SNe Ia-CSM might be due to [O I] λλ6300, 6364, adding to the evidence for oxygen emission.”
If understood graph 4, SuperNova 2008cg really ‘blasted’ CSM [Mother Nebula] away.
Should comment something: Not the big objects, maybe not the small ones, perhaps the little ones survived at exilium.
Better yet, as you point: E. Casuso and J.E. Beckman go down the scale, when suggesting the survival of big grains [Maybe those at outskirts?].
Every scale of [solid] matter should be treated as a different entity. Come on, We have the computing power.
[page11] Here is the lexicon: “the SN ejecta may be interacting with thin, relatively dense, slowly moving [compression?] shells of CSM that have cavities on either side of the shell, as one would expect from recurrent [same?] nova eruptions” [Effect of Star providing a stable axis?]
[page9] And finally found what you are talking about: “In more typical SNe IIn (i.e., ones that almost certainly came from the core-collapse of a massive star), decreased flux in the red wing of Hα compared with the blue wing has been interpreted as a sign of new dust forming in the post-shock material (e.g. Fox et al. 2011; Smith et al. 2012).
[cont. on page17] “…It is also plausible that some SNe IIn that can be described by many of the items listed above are, in fact, SNe Ia-CSM where the CSM interaction is too strong or begins too early for any hint of an underlying SN Ia to be identified.”
“Detailed modeling of both the core collapse of massive stars and the thermonuclear explosion of WDs (with an assortment of binary companions) within various arrangements of CSM is beyond the scope of this paper, but we hope that future theoretical work on this subject will be informed by the observational results presented herein.”
[Theoretical models have to fulfill observational results].
Both Star kinds are strong oxygenator candidates.
Logan,
thanks for investing your time for the review!
I’m going to see the Rosetta mission filling in some data points into the big knowledge void about the interstellar medium (ISM) before the formation of our solar system, and back to the stars feeding the ISM.
Really great would be age estimates of the dust grains, so that we get a picture of the star formation environment of our Sun. How many predecessor stars were involved, which types of stars, and when? Are there remnants of old solar systems conserved in the comet? Can we learn something about these old solar systems?
“… How many predecessor stars were involved, which types of stars, and when? ”
If Science so ready to accept Star generations and Nebula genealogy, why not so about comet-esimals’? Lack of data? Too much speculative?
[Seems to be not that much difficulty to talk about the first ‘hours’ after the BigBang…]
Star populations evidenced by metallicity:
https://en.wikipedia.org/wiki/Metallicity
Old cometesimals would have formed in low metallicity environment, hence less likely, not impossible. Relative velocities possible problem; collisions return dust.
Evidence could be provided by isotope ratios:
https://en.wikipedia.org/wiki/Radiometric_dating
But not quite straightforward.
Less likely just means rare in this case. Sufficiently large number of samples could possibly find these rare old grains.
Hope GIADA or Stardust ready for “surprises”.
Finding whole “old” cometesimals would be superexciting beyond expectations – I don’t think so.
Dense fragments of old planets better chance to survive collisions, still unlikely to find. More likely have been gas giants, if existed.
Finding single small “old” grains would be a first step to look deeper into the past. Those may have fomed in early star populations. Grains showing old alteration only possible in a larger parent body would be interesting.
Reality more humble:
https://www.hou.usra.edu/meetings/lpsc2014/pdf/2348.pdf
This single post has told a lot about the Status of the issue. Thanks a lot, Gerald 🙂
“…Are there remnants of old solar systems conserved in the comet? ”
Then comets would be compositionally ‘multi-aged’. Then not a lot case on trying to position their time or place of ‘bird’ 😉
This is cometary fiction.
Star population theory very dubious Gerald. Consensus once again. And radiometric dating nothing like as reliable as some of you believe and suggest. Your confidence implies that nothing could have happened in millions of years that could have had any effect on the isotope ratio. Hmmm.
Consensus among those who know what they are talking about, is good for me, combined with my own consistent understanding. It’s clear, that things are more complex than they look from a distance. But the general trend from low to higher metallicity is clear. You may look at the spectra of very distant galaxies, meaning into the past, to get an idea, how galaxies and their elemental abundances change over time, statistically..
Possible issues with radiometric dating are well-known, and considered, even exploited. Therefore I’ve written “But not quite straightforward.”
ianw16 says :
“Not to mention the fact that a number of comets have been studied in x-ray from spaceborne platfoms. Such a huge increase in the solar wind density, and its subsequent interaction with cometary neutrals, would be very obvious. No real need to say that this has never been seen. Must be the SW in stealth mode.”
To begin with Ian, the very fact that comet nuclei emit X-ray radiation AT ALL and with such utterly unexpected and unpredicted (by the standard theory) intensity is ALREADY proof of the “huge increase in the solar wind density” around comet nuclei whose occurrence you are curiously seeking to deny by bringing up the issue of cometary X-ray emissions….
Above all, while often invoking selected episodes and aspects of the history of cometary exploration and research, you somehow seem to have forgotten the utter amazement with which the first detection of X-rays being given off by a so-called “dirty snowball” was greeted back in 1996 when, to quote the NASA/science news article https://science.nasa.gov/science-news/science-at-nasa/2000/ast23aug_1m/, “Astronomers using ROSAT decided to look at Hyakutake and they were shocked by what they saw. ROSAT images revealed a crescent-shaped region of x-ray emission around the comet 1000 times more intense than anyone had predicted!” The predictive ability of the standard theory was already starting to be severely challenged by the embarrassing reality of actual observations and it has ever since been going from bad to worse…
The article then goes on to describe the subsequent Chandra observations of X-rays on comet LINEAR in 2000, hypothesized as a simple “charge exchange” phenomenon, in the following terms, which take on a whole, extraordinarily high, level of significance in the light of last week’s long-awaited disclosure of “very abundant” oxygen pouring off 67P (without forgetting the nitrogen also detected by ROSINA, some months earlier):
“One of Chandra’s instruments, its Advanced CCD Imaging Spectrometer (ACIS), is able to pinpoint x-ray emission from particular types of atoms. ACIS observations of Comet LINEAR revealed a strong x-ray signal from oxygen and nitrogen atoms that had lost most of their electrons, such as O6+. It’s easy to remove one or two electrons from an atom like oxygen, but stripping away six electrons is hard to do. IT CAN ONLY HAPPEN IN A HIGH-ENERGY ENVIRONMENT WHERE VIOLENT COLLISIONS OR STRONG RADIATION DISRUPT THE ATOM. STRONGLY CHARGED IONS ARE NOT PRODUCED BY THE RELATIVELY GENTLE VAPORIZATION OF COMETARY ICES, but they are common near the core of the Sun and in the Sun’s super-heated outer atmosphere, the corona. SCIENTISTS BELIEVE THAT THE IONS DETECTED BY CHANDRA AROUND COMET LINEAR WERE CARRIED THERE FROM THE SUN’S CORONA BY FAST-MOVING SOLAR WINDS.” (my capitals for emphasis).
Well, well, well! It is now thus clear that this alleged high-speed transport from the Sun’s corona of heavily ionized oxygen was only hypothesized in the first place because no-one in the mainstream community ever imagined for an instant up until Rosetta’s recent paradigm-shaking findings that comet nuclei could THEMSELVES be the source of huge quantities of molecular oxygen as has now been proved to be the case (cf. Kathrin Altwegg’s “in denial” admission). And when the article states that (I repeat) “It’s easy to remove one or two electrons from an atom like oxygen, but stripping away six electrons is hard to do. It can only happen in a high-energy environment where violent collisions or strong radiation disrupt the atom”, we are now left to infer, in all logic, that these “violent collisions” and “strong radiation disrupt[ing]t the atom” are taking place in the “high-energy environment” of the *comet itself*, where the oxygen and nitrogen are being produced. Good grief! (and I mean that quite literally…!)
Presumably only “a HUGE increase in the solar wind density” (to quote your attempted refutation, with my capitals for emphasis) via an electrical pinching mechanism focusing on the nucleus, could produce such violent events and thus so heavily ionize the oxygen molecules now known to be pouring so abundantly off comet nuclei. These then react with solar wind hydrogen to produce the observed hydroxyl and water molecules. There is thus no longer any need whatever for the hypothetical, elusive sub-surface ice. The spectacular collimated jets and violent outbursts have absolutely nothing to do with ”sublimating ice”, they are simply the visible, material manifestations of the “high-energy environment” created by ongoing electrical exchanges between the plasma in the coma and the plasma making up the solar “wind”.
QED.
Like a jack in the box, the resident EU spin doctor comes to life as soon scientists make a “surprising” discovery.
Sorry to disappoint you but the O2 molecule is neutral gas not a plasma.
As a result it won’t conduct a current to form a magnetic field resulting in a Lorentz force with an external magnetic field. This would form the basis of your “electrical pinching”.
Being paramagnetic the O2 molecule will simply orientate itself with an external field.
O2 gas=No electric current = No magnetic field= No Lorentz force with external field = No pinching = No conditions for ionization of O2 moleclues.
QED.
Sjastro your debunk has been debunked in the blog thread that you hyperlink to.
And now sjastro, a permanent diamagnetic cavity assumed from a single measurement and a complete lack of proton flux assumed at the nucleus surface, despite no actual measurement of proton flux near the nucleus surface. Excuse my mirth.
On the Moon, unsuitable though it is as a comet analogy, (because it has a near circular orbit around the Sun, as Earths partner, because it has no coma, because it has no hydrocarbon coating and because it is relatively large) , I can agree it is indisputably rock and has silicates. It does not however have a single dipolar magnetic field. It has isolated and separated magnetic fields associated with particular crustal features.
As I have explained to you already oxygen is not depleted by proton radiolysis. Both silicon and oxygen are removed in the same ratio as they exist in the rock. The Si/O ratio in the remaining rock is unchanged.
i do not understand the point you are making about “rain on the Moon”. Perhaps you could express it in another way. As I understood before you were asserting that a proton reaction with combined oxygen was more favourable to the point of exclusion of the proton radiolysis of oxygen. I have dealt with this elsewhere. However the lack of hydrocarbon on the Moon’s surface means that there is no alternative water production route there to the proton +O > OH > HOH. The OH and HOH must still survive the subsequent proton flux to persist. The release of oxygen by proton radiolysis provides free oxygen to combine directly with post impact protons. It would be indistiguishable however from OH formed by the other route and subject to the same limitations. All would be surface reactions and the products would be expected to remain on the surface. Anyway nothing like the comet situation where the hydrocarbon is a key factor as is the plasma discharge.
You have confused yourself into a bizarre implication that an electric comet could only be active remote from the Sun by your assumption that the diamagnetic cavity is permanent nearer the Sun and that it covers the whole nucleus surface. No evidence of either of these at all. In fact the electric comet model requires the proton current density and the discharge activity to typically increase as perihelion is approached, as generally observed. It is however possible with other cause, related to the relative charge of the comet and its environment, for activity to decline or stop in the vicinity of the Sun. This has been observed with other comets. It has also been observed for comets to become relatively or completely inactive near the Sun and then to flare up again suddenly in the vicinity of Jupiter. The factors controlling activity are complex and not necessarily linear and of course not easy to align with the sublimation model.
The electric comet is far from an absurd concept as measurements yet to come will prove beyond doubt. You think it is an open and shut case, problem solved beyond dispute, but let’s see the measurements anyway shall we then we can continue the discussion.
You wrote,
“Sjastro your debunk has been debunked in the blog thread that you hyperlink to.”
Your “debunking of my debunk” involves the following.
(1) Ignoring the rebuttals and repeating the same nonsense over and over again.
(2) Ignoring the evidence.
(3) “Creating” evidence to support your logically inconsistent arguments.
For example the density of the comet cannot be right hence there must be a physical variation of G.
(4) On the very rare occasion where you attempt to defend an issue, you end up creating a more absurd scenario.
For example the Si/O depletion ratio which I will describe in detail below.
You wrote,
“And now sjastro, a permanent diamagnetic cavity assumed from a single measurement and a complete lack of proton flux assumed at the nucleus surface, despite no actual measurement of proton flux near the nucleus surface. Excuse my mirth.”
Originaljohn if you had the ability of joining the dots and knowing some basic science there would be no need for you to be so mirthful.
The comet lacks an intrinsic magnetic field and any measured magnetic field is a contribution from the solar wind. The fact that Philae did not measure a magnetic field on the surface indicates the solar wind never reached the surface and your “proton smashes into the surface mechanism” ends up in the dust bin.
One doesn’t have to measure the proton flux as a zero magnetic field indicates there is no proton flux hitting the surface.
You wrote,
“On the Moon, unsuitable though it is as a comet analogy, (because it has a near circular orbit around the Sun, as Earths partner, because it has no coma, because it has no hydrocarbon coating and because it is relatively large) , I can agree it is indisputably rock and has silicates. It does not however have a single dipolar magnetic field. It has isolated and separated magnetic fields associated with particular crustal features.”
Now you are throwing in red herrings. The orbit and size of the Moon are irrelevant. Using your own mechanism the combustion of this comet hydrocarbon layer is due to protons penetrating this layer and initiating reactions with the underlying “silicate rocky layer” exactly as one would expect to see on a bare lunar surface.
The fact that sample silicate lunar rocks are like their Earth counterparts indicates your mechanism fails for both the Moon and comets.
You wrote,
“As I have explained to you already oxygen is not depleted by proton radiolysis. Both silicon and oxygen are removed in the same ratio as they exist in the rock. The Si/O ratio in the remaining rock is unchanged.”
This is ridiculous.
One of the basic building blocks of silicates is the [SiO4]4- group.
There are four oxygen atoms bonded to every Si atom which form a tetrahedral shape.
To preserve the depletion ratio four O atoms would need to be removed per Si atom.
For this to occur these very clever protons will need to navigate around the surrounding O atoms and collide into the Si atom which is sterically hindered by the four O atoms. The collision cross section would be very large as the proton is likely to lose energy through scattering given that the Si atom is surrounded by a negative charge from the O atoms.
The colliding proton needs to take out all four O bonds to the Si atom in a collision, not one or two or three which would leave [SiO3]2-, [SiO2], and [SiO]2+ fragments respectively.
The follow up chemistry would be anyone’s guess.
Even if we assumed this nonsense was possible where does the Si go?
If it redeposits on the surface, the Si/O ratio will differ from Earth rocks.
The alternative is upwards. Where is the evidence of a “Si atmosphere” around the Moon.
Given the moon has been bombarded by the solar wind for around 4.5 billion years, one would expect silicates to be completely stripped from the surface of lunar rocks.
To top it off here is a paper where silicates are irradiated in the laboratory with H+ and He+ ions simulating the solar wind.
https://www.pnas.org/content/111/5/1732.full.pdf
The only depletion that occurs is the metal cation bonded to the silicates. The Si and O atoms stay put but the metal cation/O ratio decreases.
You wrote,
“i do not understand the point you are making about “rain on the Moon”. Perhaps you could express it in another way. As I understood before you were asserting that a proton reaction with combined oxygen was more favourable to the point of exclusion of the proton radiolysis of oxygen. I have dealt with this elsewhere. However the lack of hydrocarbon on the Moon’s surface means that there is no alternative water production route there to the proton +O > OH > HOH. The OH and HOH must still survive the subsequent proton flux to persist. The release of oxygen by proton radiolysis provides free oxygen to combine directly with post impact protons. It would be indistiguishable however from OH formed by the other route and subject to the same limitations. All would be surface reactions and the products would be expected to remain on the surface. Anyway nothing like the comet situation where the hydrocarbon is a key factor as is the plasma discharge.”
The point I was making is that the formation of water in situ in lunar rocks can only be explained via the preferential reactions that are determined kinetically and thermodynamically. How do you account for water in moon rocks when the O is sputtered off the surface by your mechanism. You can’t and water in moon rocks is yet another piece of evidence that refutes your theory.
You wrote,
“”You have confused yourself into a bizarre implication that an electric comet could only be active remote from the Sun by your assumption that the diamagnetic cavity is permanent nearer the Sun and that it covers the whole nucleus surface. No evidence of either of these at all. In fact the electric comet model requires the proton current density and the discharge activity to typically increase as perihelion is approached, as generally observed. It is however possible with other cause, related to the relative charge of the comet and its environment, for activity to decline or stop in the vicinity of the Sun. This has been observed with other comets. It has also been observed for comets to become relatively or completely inactive near the Sun and then to flare up again suddenly in the vicinity of Jupiter. The factors controlling activity are complex and not necessarily linear and of course not easy to align with the sublimation model.”
As long as the comet has a coma which is formed as it nears the Sun due to sublimation, the diamagnetic cavity is formed in the inner coma at a boundary where the coma exerts enough pressure on the solar wind to keep it at bay.
Its called a diamagnetic cavity because the magnetic field associated with the solar wind stops at this boundary and the solar wind which behaves like a fluid will flow around it. The diamagnetic cavity or boundary expands during periods of intense outburst activity.
https://www.esa.int/Our_Activities/Space_Science/Rosetta/Comet_s_firework_display_ahead_of_perihelion
Where does this leave your combustion or electric comet model or whatever term you use describe it? Basically up the creek without a paddle.
Not only can your model not explain why the diamagnetic cavity expands but is totally contradicted by the its existence as your so called proton current (which actually doesn’t exist) and electrical discharge would go all the way down to the surface. If this was the case a magnetic field have been measured.
Rather than accepting the evidence you go into full blown denial mode claiming no such evidence exists and go down blind alleys.
We disagree sjastro about what the evidence such as it is means and what in fact is evidence and what is not. As far as I am concerned that is the end of the argument. You are welcome to your opinion and interpretation and I will stand by and reiterate mine. Leave it to the readers to decide who is more rational and objective in relating the observed behaviour of comets to likely mechanisms and then wait for the big gaps we have in the data to be filled to prove you are barking up many wrong trees.
Oh by the way I will educate you in one significant respect with regard to your assertion about the Lorentz force. Without the filamentary flow of current in a plasma there is no Lorentz force therefore filamentation stands at the beginning of the sequence. However the continued effect of the Lorentz force throughout the sequence increases current density and consolidates filamentation. You chose the wrong metaphor therefore with the cart and the horse. Chicken and egg would have showed some perception.
Oh and the protons and electrons in the solar wind current are indeed moving in opposite directions.
Oh and I note that you choose to ignore Dr Glassmeier’s confirmation that the comet we are observing does exhibit a magnetic field.
Originaljohn,
“… the protons and electrons in the solar wind current are indeed moving in opposite directions.”
Relative to which observer? Which ratio? Reference please.
“Oh and I note that you choose to ignore Dr Glassmeier’s confirmation that the comet we are observing does exhibit a magnetic field.”
Which field strength? Reference? Consequences?
If I remember correctly, we are talking about a few nano Tesla, at most, as upper bound.
Your statements are too fuzzy, Originaljohn, to be meaningful. More substance, please.
Otherwise it looks, as if you’re again trying to create legends out of nothing.
Sjastro, I am interjecting in your dispute with THOMAS to observe that once again you attempt sarcasm as insult. It diminishes your argument sjastro, which does not stand scrutiny anyway.
As I understand both molecular and ionised oxygen have been detected in the coma. I know THOMAS is well aware of this. You appear not to be.
Also you fail to grasp the Lorentz force aspect. There are ions aplenty in the solar wind plasma and it is this flow of current, the solar wind proton current, that can become naturally pinched and accelerated and greatly increase the energy input into the comet nucleus surface, acceleration occurring at the electric field boundary between the nucleus and the coma, as well as at the coma boundary with the interplanetary medium, and possibly elsewhere in the coma.
solar wind plasma filaments = electric current = radial magnetic field = Lorentz Force = multiple plasma pinches = extreme current density + natural boundary accelerations = sufficient energy density at the nucleus surface for all the observed effects and some yet to be observed.
Originaljohn once again you demonstrate a lack of comprehension. Claiming that I did not read the article or do not understand the Lorentz force concept is dishonest, hypocritical and mildly amusing.
Whereas a current is composed of moving charges, the converse is not necessarily true. Moving charges in a current are driven by an electromotive force and opposite charges move in opposite directions. The solar wind is an example of moving charges that is not a current. It is ludicrous for you to refer to a “solar wind proton current” when the electrons are moving in the same direction.
There are ways of creating a current in the solar wind and ultimately a “filament”, such as a time varying external magnetic field that induces the current. Unfortunately for you the comet does not have a magnetic field let alone a varying one.
Your chain of events “solar wind plasma filaments = electric current = radial magnetic field = Lorentz Force = multiple plasma pinches……….” illustrates you have no understanding of the subject.
The “solar wind filaments” are created as a result of the Lorentz forces and should be at the end of the chain, not at the start. This is the classic case of putting the cart before the horse and a circular argument in operation. As a result the rest of your mechanism doesn’t follow.
The generation of an electric current as result of this “solar wind filament” is another question in itself…….
You seem to be struggling with what is the cause and what is the effect.
Repetition of same old pseudoelectric nonsense soup.
Ignorant of physics and data. Measurements replaced by ideology.
The mere ability of the Rosetta probe to send data and to survive the space environment rules your “extreme current density” definitively out.
“Extreme current density” produces “extreme” magnetic fields, in strong contradition to magnetometer measurements.
The comet is not a Tokamak nuclear fusion reactor. There is a “tiny” but perceivable difference, the difference is a little larger than between a nuclear magnetic resonance (NMR) tomograph and, say, the Gobi Desert.
Well, ok, that’s maybe the same for electric universe proponents, but with some will, you might learn to find out the tiny little difference.
None of the reply links working, so these threads no doubt busted up. Main post for bottom still works, so this is @ Thomas. Just wanted to say, Thomas, you’ve laid out some scorching posts here. Can almost smell the singed eyebrows. Nicely done. I guess no answers to your posts (that I’ve seen at least) is sometimes the most revealing answer.
SS
I’m afraid Thomas’ posts scorch no eyebrows at all; they do cause combination of amusement and irritation to those allergic to pseudo science. They are *replete* with basic scientific errors at the most fundamental level, and frequently a complete lack of understanding of what the measurements mean.
I’m not talking about Whipple v any other model, I’m talking about conservation of charge, energy, moment etc etc. Also for example claiming two measurements are incompatible when they measure different things, utter mangling of things like electromagnetic induction, etc etc.
This isnt about ‘closed minds’, ‘establishment bias’ etc etc; its about the most basic, absolutely firmly established physical ‘laws’.
The lack of responses was a cata issue.
(Capta prevents replies in the right place.)
Thomas; re ‘conflicting’ oxygen measurements.
They are not incompatible, because *THEY ARE MEASURING COMPLETELY DIFFERENT THINGS*
ALICE is measuring OI, atomic oxygen.
The results here are for O2, molecular oxygen, a completely different species likely to have completely different origins.
Whilst they might be *some* linkage (eg, via photodissociation of O2?) there is absolutely no reason to expect the two measurements to ‘agree’ in a simplistic sense.
Capta problem forces reply here.
Thomas:
That sylph-like young comet called Chury,
Had been on a diet must surely
Its mass was so slight
It slipped by in the night
But its density’s known quite securely.
Thomas; in more coventional form, re density.
A density requires a volume and a mass.
Unless both OSIRIS and NAVCAM are really rather drastically miss calibrated – to put it mildly – I think we know the volume rather well.
By now ESA must have literally thousands of measurements of the position of Rosetta relative to 67P from imagery, and its velocity from radio Doppler measurements. From that we deduce a mass using standard gravitational theory.
To falsify that measurement, the force messing things up must have the same variation as gravity and opposite sign, & the only one available is electrostatic repulsion; but a trivial calculation shows the numbers required are insane, & would lead to a multitude of other obvious effects. Furthermore the charges on Rosetta & 67P (strictly, the product of the two) has apparently remained exactly constant, despite these fictional discharges and change in distance to the sun. In addition the charge distribution would have to mimic the mass distribution, to the extent that is determined by the data on Philae & Rosetta. Philae’s ‘rebound’ in particular is a complete ‘killer’ for this nonsense; it would have neutralized on contact and shown totally different dynamics; it didn’t.
In addition the limited CONSERT data would report *far* higher real parts of the dielectric constant if it were ‘sold rock’.
Unless there is totally new physics operating,every scrap of evidence is that the density is ROBUSTLY established at 470kg/m^3
(Its also of course broadly consistent with what has been seen at other comets.)
You change your theories to fit the evidence, not the other way round. *ALL* theories have to live with that.
Cant post in the right place, capta problem.
Marco.
You say that
“I have suggested thermal conduction (of the sun’s heat) through a thick (non-porous) crust rich with PAHs which are as thermally conductive as metal.”
Could you provide some *a reference* for the high thermal conductivity of PAHs? I’ve looked but not found one. Metallic thermal conduction is largely electron mediated. PAHs do not have metallic electrical conduction. One quickly to hand, anthracene, has a K of just 0.1416W/(m.K) at 240C according to Wiki; FAR lower than metals which are tens to over a hundred W/(m.K)(though anthracene would rise towards 0C if behaving as an electrical insulator.) Anthracene is probably too volatile to be a candidate though. The rest don’t seem to have K reported, suggesting its nothing special, and a quick search threw up nothing suggesting PAHs have unusual thermal conductivity.
As it happens I’ve spent several weeks mired in calculations involving thermal conductivity – albeit of different materials in a different temperature range – but if true, the mechanism is interesting.
Can you provide a reference please.
We are getting quite a lot of ‘reasoning’ along these lines, from Thomas, but from others too:
“Since the hydroxyl/water detected in comet comas is thus seen to be the result of a continuous, large-scale oxygen + hydrogen reaction, …….”
Remember that *molecular water* is unambiguously measured by MIRO & a few earlier ground based instruments; hydroxyl has been measured for decades.
I can see why this might seem ‘natural’; but unfortunately it relies on an ‘earth bound’ image of chemical reactions; it’s *very* different in the comet environment.
But before addressing that, remember that *the supply of protons from the solar wind is extremely weak*; there are many, many orders of magnitude too few to supply the hydrogen to make the observed quantities of water. But that’s another story.
We think of H2 and O2 as, obviously, reacting to form water. 2H2+O2=2H2O, schoolboy stuff.
Firstly of course you can mix H2 & O2 *and absolutely nothing happens* until you ‘ignite’ it.*
That leads to a propagating reaction, & a nice loud BANG
But only at relatively high pressure; it requires the collisions between molecules to transfer the excess energy liberated from one reaction to initiate the next.
Incidentally that H2/O2 mixture stays there quite happily despite the odd cosmic ray, despite weak alpha & beta emission from radioactive materials in the container, even at one bar. These deposit too little energy to get a propagating reaction going. In industry, very intense alpha sources (usually based on Po210) are placed very close to high speed moving, *inflammable* plastic films in air to prevent electrostatic charging; they don’t ignite, same reason. A hydrocarbon, in (partial) 0.2 bar oxygen, strongly illuminated with MeV alphas – doesn’t ignite. I suspect a ‘sufficiently intense’ radioactive source could ignite a flammable gas mixture maybe; but we are talking something *UMPTEEN* orders of magnitude stronger than the solar wind.
Furthermore, reactions like A+B=AB, even if exothermic, cannot readily happen at low pressure, because they cannot readily simultaneously conserve both energy and momentum. At high pressure, it’s A+B+X->AB+X* where the ‘inert’ X carries off energy & momentum to balance things up.
Reactions of the form A+B->C+D have an easier time satisfying conservation laws.
So to consider whether solar wind protons (of which, I reiterate, there are far too few) could react with molecular oxygen to form molecular water is not a straightforward matter.
(Quite energetic in chemical terms) H+ plus O2 can’t form water; you are short of an electron & a hydrogen & have one too many oxygen atoms. You need a step by step list of credible processes to get from there to water – in a low pressure environment. The more steps, the rapidly less likely it becomes, because of the very low density.
I’m afraid ‘obvious’, schoolboy chemistry arguments just don’t apply.
Harvey ‘getting quite a lot of reasoning of this kind’.
Harvey your blog is a nice peiec of reasoning about what is not happening and why, thats great I always admire your blogs, but, as always what actually is going on? The free O2 pooring of the surface plus other than condensed Ice on the surface, water ice is still mysteriously playing hide an seek.
The O2 blog was such a surprise – what is actually going on and how?
Its a bit of a rhetorical question, but Im sure you can see we are all on the edge of our seats lots of different theories from all sorts of people, but the what and the how remains illusive.
regards
The evidence appears to be that the comet is indeed producing a large & unexpected flux of molecular O2.
A very interesting result, which indeed seems to challenge some established ideas; great!
How it got there I do not know, & needs much further thought. I don’t consider myself an expert on that, so, unlike others, I don’t comment of things I don’t understand pretty well.
But there is little point in including in that process mechanisms which blatantly disregard basic physics & chemistry & misinterpret the observations.
Dave, they just identified neutral O2. You’ve now the choice between waiting for well-founded answers obtained from follow-up research, or out-of-the-hip answers, which may or may not turn out to be correct.
One out-of-the-hip answer might be, that a supernova or an aging star released oxygen (and other elements) to the interstellar medium. (Oxygen has been in excess of carbon, hydrogen and silica.) The excess oxygen formed O2, (either directly or via decomposition of intermediate H2O2) and cooled down to close absolute zero (to a few Kelvins), such that it condensed (resublimated) on silicate grains (which formed at more than 1000K near old stars or supernovae). It either resublimated together with water vapor to form a clathrate, or as H2O2 to later decompose into a H2O / O2 clathrate hydrate, or it formed a coating on top of a water ice layer.
The interstellar dust later locally densified (e.g. by a nearby supernova, or some random instability). The densest part of the cloud collapsed to the Sun. Surrounding gas and dust formed a disk by friction and release of excess heat.
This protoplanetary disk contracted locally to form cometesimals and planetesimals. Those then merged to planets, asteroids and comets; some were ejected out of our solar system, some fell into the Sun.
Comets have always been in the outer parts of our solar system, sufficiently far away from the sun, not to sublimate away (those closer to the Sun lost most of their volatiles, hence lost their property of being a comet).
By some gravitational disturbance, e.g. by a nearby star, or by planets within our solar system, some comets happened to change their orbit to closer to the Sun, with the effect, that the ices started to sublimate (by solar heat), with the evolving gas dragging dust off the comet, visible as jets.
When sublimating, the ices release their compounds, like H2O, CO2, CO, N2, O2. The dust is made of the silicate grains which initially served for ices to nucleate.
On some silicate grains volatile organic components nucleated; those grains aren’t well-suited for water nucleation. So we get hydrophilic and hydrophobic grains.
All “baked” together in a more or less random mix as a comet.
… to prevent mis-understandings: The most abundant elements of the collapsing cloud are hydrogen end helium; then oxygen.
But locally and temporarily after a supernova explosion or near aging stars, oxygen may be most abundant.
It then cannot react with (lack of) hydrogen.
Later, after cooling down, oxygen can coexist with hydrogen.
Find Gerald’s the most preferable version of 67P’s history, within the blog 🙂
Thanks, Logan, just gluing pieces together 🙂
SS: What is questionable about the scientific processes and methodology? In my opinion they did a pretty thorough study on this paper, and they put out their conclusions. I do not begin by suspecting that the authors are not doing their work properly. As I said earlier, any one who has a better and smarter model will be out with their paper at the next conference. No one is “rushing to judgement”, this is not a court case. Everybody on this blog is expressing opinions. You have opinions on what you think being “scientific” is and this colours your opinions on other matters.
Hi Gerald,
Regarding your comment on my thermally conducting crust.
I am not questioning the observations, and I am not discarding the mechanism, except for the withdrawal of the requirement that the Oxygen be all dissolved in the water. Most of it would exist as a gas in whatever voids makes the density low. The Oxygen gas would be escaping proportionally to the water vapour gas escaping.
I disagree with the assessment that 200′ K in the polar night rules out a warm interior. The polar night lasts several months at least, and temperatures should be way lower.than that if the interior was “tens of Kelvin”
A Carnot cycle would indeed exist if the heat conducted down warms the liquid at the interface driving convection away from the interface, but heat conducted up would cause the water to freeze and cause an insulating “igloo” layer of ice at the interface. The interface between the PAH rich crust and the liquid water layer would be tens of metres below the surface. The assumptions used for calculation of thermal inertia are completely contradictory to my thesis, so not much can be concluded from that….
Hi Marco,
re post https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-576183
At 1 bar pressure and 0°C, you need about 22.7 liters for 32 g O2 oxygen gas.
https://en.wikipedia.org/wiki/Molar_volume#Ideal_gases
22,7 liter water at 0°C are of a mass of about 22.7 kg, hence about the 709-fold.
At 20 mbar, it would be a factor of 35,450, meaning 35,450-fold the volume for the same mass of O2 gas as for liquid water.
For a low estimate of 1% oxygen relative to liquid water, still a volume ratio of 1:354.5.
At 25°C another factor of 1.09 worse, but the same order of magnitude.
So you would be off by a factor of about 1000 with respect to the observations.
Assuming much faster release of O2 relative to H2O to heal the discrepancy would have depleted oxygen rapidly.
Re thermal inertia:
Clothes protecting from cooling protect from heating as well. That’s the same for the comet, and its thermally insulating layer. You may have seen infrared images showing the effect of thermal insulation:
https://www.animations.physics.unsw.edu.au/jw/thermal-radiation.htm
Thermal conduction would show up the same way for 67P.
Hi Marco. “I disagree with the assessment that 200′ K in the polar night rules out a warm interior. The polar night lasts several months at least, and temperatures should be way lower.than that if the interior was “tens of Kelvin””
It is, indeed, much lower, i.e. in the lower 10s of K range.
200K would be evidence for a warm interior, and high conductivity, but it’s more like 20K at the polar night.
(When did I say 200K?, maybe below -200°C)
200 K have been near the upper end on insolated surfaces near 3 a.u. from the Sun.
Harvey,
as I’ve read between the lines, Marco has been referring to in-plane thermal conductivity of graphene:
https://arxiv.org/ftp/arxiv/papers/1301/1301.6181.pdf
That’s of course not applicable to PAHs in general, but although very very unlikely, it’s equally impossible to disprove entirely. You would need a highly crystalline arrangement of rare PAHs. On the comet purely hypothetical in my eyes. In some laboratory, maybe.
Gerald. You are probably right!
Though last time I looked graphene & graphite were a tad short of the ‘H’.
Yes, there might be a little of either on 67P I guess. But the IR signature is clearly C-H. And did little green men carefully stack they all up the right way? 🙂
! 🙂
Hi Marco,
I’d like to learn more about your proposed Carnot cycle.
How is nature forced to work the opposite way it usually does? What’s the mechanisms?
Besides the invisible and unmeasurable “electric universe” wirings I don’t see the source of energy nor the motor driving convection backward.
@Thomas,
Sorry wrong again.
You seem to have forgotten all the instruments that would measure these non-existent pinches, or whatever electric woo you are proposing. Why is it invisible, after 15 months, in every conceivable orbital configuration and distance?
Why have they never been seen before at any comet? Why do we even need to invoke them?
15 months alongside this comet, and EU still has zero evidence of anything. I think that needs to be stressed.
30 years ago we were sure H2O had to be in the coma of comets. KAO subsequently proved it in 1986. EU were still denying that it was H2O, and was being mistaken for OH! (LOL) until recently (or maybe still are?) It has subsequently been found on many comets. Unambiguously. 200 000 l/s at Hale-Bopp. Lot of water, is that.
10 years ago we knew comets had to have ice beneath their surfaces, and DI subsequently proved it. at Tempel 1. Unambiguously. It was seen in the jets at Hartley 2 some years later. Unambiguously. Seems like MIRO has detected it in the southern region of this comet. Shouldn’t that be rock, by the way? Where is all this rock?
So, as I said, you are inventing unseen/ impossible mechanisms to explain away something that is already a done deal. Comets have ice beneath their surfaces.
As for the x-ray data, yes, it wasn’t a mechanism they had considered prior to Hyakutake. However, since then there is nothing in the data (scientific papers, not cherry picked media releases) that tells us that it is anything other than charge exchange between the SW and cometary neutrals.
Quite why you had to capitalise the sentences you did is beyond me. Of course these minor, high energy ions were formed by the Sun. Where else are you expecting the solar wind to come from? Mars? Ions reach comet, ions CX with cometary neutrals, X-rays produced.
Charge Exchange-Induced X-Ray Emission from Comet C/1999 S4 (LINEAR):
https://www.sciencemag.org/content/292/5520/1343.full
CXO X-ray spectroscopy of comets and abundances of heavy ions in the solar wind:
https://www.researchgate.net/profile/Vladimir_Krasnopolsky2/publication/267572307_CXO_X-ray_spectroscopy_of_comets_and_abundances_of_heavy_ions_in_the_solar_wind/links/546a15690cf20dedafd380a0.pdf
Nothing in either of those, or many more, that would be of any help to EUs non-existent mechanisms.
Logan “Think you have kind of a Gordian Knot there, Gerald”.
Only a problem for some intuitionists:
https://en.wikipedia.org/wiki/Intuitionism
““We humans have funny ways of solving problems that no one’s been able to articulate,”
Warren Powell, director of the Castle Laboratory at Princeton University’s Department of Operations Research and Financial Engineering.
https://nautil.us/issue/3/in-transit/unhappy-truckers-and-other-algorithmic-problems
Our most relevant problems are not mathematically describable, not remotely.
Describable mathematically, they are.
Described in detail, no.
Description not equal solution.
If described, beyond human cognition.
Made this doing machines;
better not repeat.
Switch off.
Not a toy.
Too easy to get out of control.
Makes human redundant,
before solving problem.
Replaces problem by bigger one.
Think twice.
Be humble.
Modern homunculus.
“The success, when it comes, has to be tested rigorously and then it has to be considered for what it doesn’t tell us, not just what it does tell us. It has to be used to get to the next stop in our ignorance—it has to be challenged until it fails, challenged so that it fails.”
“…But failure is not backsliding in science—it moves things forward as surely as success does. And it should never be done with. It should become a habit.”
Find this so Aristotelian that can’t explain to Marco why also is so Scientific.
Stuart Firestein is a professor of neuroscience in the Department of Biological Sciences at Columbia University. He is a fellow of the American Association for the Advancement of Science, a Guggenheim Fellow, and serves as an advisor to the Alfred P. Sloan Foundation.
https://nautil.us/issue/30/identity/why-scientists-need-to-fail-better
Gerald could say this is intuitionist, too.
Scientists have been spectacularly “failing [at] just to try again without trying to fail”.
Dangerous [Just to say the least].
Is Science -the stricter-, as many other human disciplines before, starting to ‘perform’?
Quite un-self-indulging and introspective this short article from Professor Firestein.
We can see an Engineer actively trying not to fail [at final output]. We ask for it.
[When an Engineer do testing, is making ‘small scale’ Science, ad-hoc Science, not Engineering].
But when I see a Scientist actively trying not to fail, I feel un-fulfillment, lack of rigor.
That is why I find so heart-warming that legend about the Australian radio telescope and the long lived microwave oven.
Having openly spoken about it, and documented it, is Science at the strictest. Is Science I take my hat off. Is Science I put a knee on the floor. It is Slack Science 🙂
Not needing to go too far… If Svletana had followed protocol in order to bring consistence to their Team work, Then that glass plate would had been discarded, without second thoughts. She actively tried -and succeed- at diverging.
Professor Firestein goes further on asking Contemporary Scientists to go back to healthy ancient custom of expending time -and resources- to try and succeed at failing. And see -and measure- up to which point that failing agrees with our expected ‘failure’ scenarios.
At least one ‘Igg’ project should be also selected, awarded -and carried on- at Elite Scientific Endeavors 🙂
Failure is not bad science, just the unexpected kind. The kind of science you do walking back. Deliberate failure has to be ‘programmed’, and budgeted, into elite Science.
That’s why OutReach, ‘College’ CubeSats, and similar efforts are so important, in my perspective 🙂
Some tasks are straightforward.
Challenging (interesting) tasks use to teach you abundant failures on the path to final success.
Re bulk density of the comet: If I remember correctly, after refining the shape model, the density has been adjusted from 470 kg/m³ to 510 kg/m³.
The shadowed regions seem to have been more concave than formerly estimated.
But solid silicate rock as main constituent of 67P is still clearly ruled out.
Due to the 4:1 dust/ice ratio, the comet needs to be very porous.
As GIADA has shown, some dust particles are like an aerogel, extremely porous, less dense than air.
“the fluffy particles have effective densities of less than 1 kg/m3, literally lighter than air (at sea-level)”
https://blogs.esa.int/rosetta/2015/04/09/giada-investigates-comets-fluffy-dust-grains/
@Thomas,
Further to the previous, you quote from the NASA article:
“to quote the NASA/science news article https://science.nasa.gov/science-news/science-at-nasa/2000/ast23aug_1m/, “Astronomers using ROSAT decided to look at Hyakutake and they were shocked by what they saw…………….”
All you’ve done here is what I’m afraid I see with a lot of pseudoscience posters; you not only cherry pick from press releases and the like, as opposed to the scientific papers, but are also very selective about which part of those articles you actually quote. Pseudoscience 101.
Given that the whole tenor of that article is to explain that Chandra has solved the “mystery”, then that is somewhat disingenuous, if I’m being kind.
I’ll cherry pick some quotes now:
“That problem — the enigma of intense x-rays from comets — would persist for four more years……………..until last month when Chandra observed Comet LINEAR that the answer finally emerged.”
And;
“Soon after astronomers discovered x-rays coming from comet Hyakutake, a team of scientists at the University of Michigan suggested charge exchange reactions between the solar wind and cometary gases as a possible explanation………..but it was impossible to fully test their theory until last month when Chandra looked at Comet LINEAR…………………..This observation solves one mystery. It proves how comets produce X-rays,” said Dr. Carey Lisse….”
And you obviously misunderstand the reference to the production of highly ionised ions, such as O6+. You seem to think they have been produced at the comet! What the article (and any number of papers) is saying, is that it is these ions that have been created by the Sun, and then entrained within the SW, that are responsible for the CX and subsequent X-rays, ONCE THEY REACH THE COMET. They are not produced in situ!
I stand by my original point; you increase the SW density, you increase the density of these highly ionised species also. You do that, and the X-ray production from CX would most definitely be noticeable. It hasn’t been, although they have noticed increases due to solar flares. So a billion fold increase in the SW will not go unnoticed. Even if it were possible.
THOMAS,
regarding O6+:
“Scientists believe that the ions detected by Chandra around Comet LINEAR were carried there from the Sun’s corona by fast-moving solar winds.”
“Positively charged ions like O6+ make up about one percent of this solar wind.”
https://science.nasa.gov/science-news/science-at-nasa/2000/ast23aug_1m/
What does your “QED” mean? That your comment demonstrates the unwillingness of electric universe proponents to understand solar and plasma physics?
“ESA’s Rosetta spacecraft has made the first in situ detection of oxygen molecules outgassing from a comet, a surprising observation that suggests they were incorporated into the comet during its formation.”
Related to questioning the scientific process to new findings that I’ve raised and to which others such as ianw16 have basically said I’m out to lunch concerning, and more specifically to the finding outlined in this article, I would think that instead of immediately trying to slot new findings into already agreed upon beliefs, or pointing out how it doesn’t fit current beliefs and is a “surprise,” the first order of business would be to determine or list how many known phenomena could produce this result…in others words, take the finding as is without any other consideration and build from there. But as the first line of the article says, “oxygen molecules OUTGASSING from a comet, a surprising observation that SUGGESTS they were incorporated into the comet during its formation.”” which clearly shows that there’s already a major underlying assumption at play: outgassing, which then leads to another assumption: incorporation into the comet during its formation. These assumptions are not based on any scientific process at all. They’ve revealed data, but revealing data then jumping to possible conclusions is not science. And any science done will now likely be skewed by the assumptions of outgassing and something to do with formation. Why not this approach – what are all the known processes, activities, etc for producing oxygen? Outgassing accounts for one, but there are others. How about a simple list of every known process that can produce oxygen (can’t be that many), I’m sure it would be easy for Harvey or Gerald or whoever to do. Then take each one and honestly consider each, apply some if/then logic, factor in other gathered data, and hold an open arena as more data is gathered and see what emerges. Instead, data always seems to be pigeon holed into existing beliefs, which again, is not a scientific process.
SS.
*By far* the most probable source is outgassing.
Somehow you have to find two oxygen atoms & assemble them into an oxygen molecule; it turns out that in a low pressure environment that is rather hard to do, for reasons set out previously. For example two oxygen atoms from ohotodissociated water will be very ‘reluctant’ to form O2.
Given the rather high densities observed, I very much doubt you could source anywhere near enough
It would need a full model of the environment to be sure, which would be a complex undertaking & require as yet unpublished data; but I think it would be *very* hard to find a credible alternative source.
“How about a simple list of every known process that can produce oxygen (can’t be that many)”:
Depends on the detailedness.
I’m aware of essentially three groups of processes: Those of nuclear physics producing the oxygen atomic nucleus (nucleosynthesis), the chemical ones leading to O2 molecules, and low-engergy physical processes.
Oxygen nuclei may form by fusion, by fission (photodisintegration), or by several other forms of nuclear reactions.
The list of chemical processes releasing oxygen is huge, if you go into detail. For any oxygen-bearing molecule there exists at least one option to remove an oxygen atom/ion, usually a large number of options along more or less complicated reaction paths, with or without catalysts.
Low-energy physical processes include changes of phase, like sublimation, or release from some cavity.
I wholly sympathize, Sovereign Slave, with what I sense to be your growing scepticism and frustration at how scientists often seem to be over-eager to have their conjectures on their own unexpected findings blessed and enshrined by their peers via their publications. I went through a similar process many years ago. To give vent to my own similar feelings, I find it useful to spend a few minutes trying to encapsulate an issue which is bugging me in a limerick. Here then is a double one, for double relief to double frustration, on the subject in question (with a special h/t to Lewis Carroll and his “Hunting of the Snark” for his famous insight into the curiously compelling power of ritualized expression, which I have taken the liberty of adapting slightly to make up the concluding line).
Some experts on comets now state
That they form after two snowballs mate.
When we say “No way!
You can say what you may,
But…” – “It’s published” they cry, “You’re too late!”
“But are you aware” we would argue
“That’s something pure Chance is the path to?”
Yet they just won’t hear,
Sneering “Go on and jeer,
For what we say three times is true!”
… the hungry electric wulf lurking on easy prey …
@Harvey and Gerald, great replies and thanks. Your three groups of processes Gerald seem like such a fertile ground for intellectual investigation and just playing with the possibilities with an open and uncluttered (and scientifically well informed, which mine is not) mind, especially when something unexpected like this is presented. Can’t help but think that is what may be required to go from unexpected data to perhaps the unexpected realizations needed to explain the data.
THOMAS!
So many Captcha problems! I’ve been trying to post for four days now ….
Re. your comment of 06/11/2015 at 22:17
Reading technical papers for comprehension is a skill that is easy to learn. You have apparently missed the obvious difference between the two papers. A simple mistake that someone with limited scientific experience might make.
Feldman et al. (2015) discusses ATOMIC oxygen as a dissociation product of H2O and (to a lesser extent) CO2. Bieler et al. (2015) deals with the existence of MOLECULAR oxygen in the composition of the nucleus and coma of 67P. If you reread the papers, you will realize that these findings are not at all incompatible.
Sublimation of comet ices produces water, carbon dioxide, carbon monoxide, and (according to Bieler et al. (2015)) molecular oxygen. Dissociation processes tear these molecules apart yielding ionized hydrogen, oxygen, and carbon (Feldman et al. (2015)). Simple!
I also have a concern about the source of a quote you provide in the first sentence of the second paragraph. You write, “In the present case, the May 2015 article …, published by Feldman et al., found that the oxygen of indeterminate abundance detected close to the surface of the 67P nucleus was the result of “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface”, i.e. by UV photodissociation.” The issue is with the section, “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface ….” I assume these are your “quoted” words, as I cannot find them anywhere within the Feldman et al. text. Your context implies Feldman et al. made this statement, which of course would be a lie. An explanation is warranted. What say ye, Sir?
Now, to answer all your questions ….
“Does anyone know which of these two incompatible sets of findings is the right one?”
First of all, the results are not incompatible! They deal with different aspects of comet behaviour – Bieler et al. deals with issues of nucleus composition, while Feldman et al. addresses dissociation of sublimated molecules. Both papers present stout science!
“Are we supposed to conclude, … that the Alice team members were mistaken in attributing the oxygen they detected to the rapid breakup of water molecules?”
No! Again, completely different processes are being discussed. The ALICE science team is using well established physics and chemistry to address dissociation processes and products (e.g., early research on electron impact dissociation of CO2 was conducted by Ajello (1971) and Mumma et al (1972) – both references are cited in Feldman et al.).
“Who is the arbitrator in this sort of case?”
The mainstream science community! Based on my previous statements, it should be obvious that no arbitration is required here. I find the research and results presented by both science teams to be solid. Still, there are numerous examples where different scientists will disagree on published results. When there are disagreements, the science community discusses, debates, conducts more research, develops better mathematical models (based on real, measurable physics and chemistry), and eventually, through iteration, comes to some kind of “consensus.” In the worst case, this process can take decades or ….
“Is there a procedure for withdrawing a peer-reviewed article if its findings are shown to be questionable or plain wrong?”
Yes! However, the appropriate term is “fraudulent” and there can be serious consequences. Problems associated with fraud are more often encountered where financial gain is involved. For example, pharmacology and medicine. The anti-vaccination movement, for example, got it’s original impetus from a fraudulent study that linked vaccinations with a particular medical/developmental condition.
“Can the Feldman et al. paper still be referred to by subsequent researchers to prove the supposed reality of UV photodissociation of H20 to produce oxygen on comets, even if it is now considered to be obsolete?”
The results presented by Feldman et al. are still valid! They have not been rendered obsolete by Bieler et al. As an aside, dissociation does not “produce” oxygen in the coma, it liberates atomic oxygen from water, carbon dioxide, carbon monoxide and (apparently) molecular oxygen.. Photo and electron impact dissociation are integral to the creation of an ionosphere, and in the case of comets, an induced magnetosphere and ionization tail! You may be disturbed to discover that the Feldman et al. paper has already been cited twice!
“Why is there not more coordination and communication between the various Rosetta teams before going into print so as to avoid this sort of confusion?”
There is no confusion! You, Sir, seem to be the only one confused! As I said at the outset, reading technical papers for comprehension is a skill that can be learned. Perhaps in your haste to find fault and flaw with the science, you missed this line in the Feldman et al. paper … “We also note that the electron impact cross sections for O2 to produce the atomic oxygen emissions are very similar to those for CO2, with the OI] λ1356 to OI λ1304 ratio well known to be 2.2 (Kanik et al. 2003), so that O2, recently reported in ROSINA mass spectra (K. Altwegg, private communication), could also be contributing to the intensity ratio increase observed by ALICE.” That is but one example of communication between the various Rosetta science teams! You can find countless others when you read for comprehension!
@ Booth
You write:
“In the present case, the May 2015 article …, published by Feldman et al., found that the oxygen of indeterminate abundance detected close to the surface of the 67P nucleus was the result of “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface”, i.e. by UV photodissociation.” The issue is with the section, “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface ….” I assume these are your “quoted” words, as I cannot find them anywhere within the Feldman et al. text. Your context implies Feldman et al. made this statement, which of course would be a lie. An explanation is warranted. What say ye, Sir? »
This is what I retort, my dear man: The statement referring to “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface” is not my invention, as you claim: it is true that it does not come from the article itself, but it is as near as damn it, Sir! It is actually quoted from the introduction to the official ESA blog-post presenting the findings of the article: https://blogs.esa.int/rosetta/2015/06/02/ultraviolet-study-reveals-surprises-in-comet-coma/. It is thus a synthesis of the article’s main findings and of the authors’ value judgment on them, as is confirmed by the words of one of the authors reported lower down in the blog-post: “The discovery we’re reporting is quite unexpected,” says Alice Principal Investigator Alan Stern. […] “And, it is fundamentally transforming our knowledge of comets.” Moreover, the blog-post was necessarily read and approved by a representative member of the research team (no doubt by “Alice Principal Investigator” Alan Stern in person…) before publication.
So your insinuation that the words I quote in any way misrepresent the paper’s findings (and might even be considered as tantamount to a “lie”) is utterly groundless. My position stands, Sir! And if you are simply quibbling with the fact that I did not explicitly attribute the quotation to the covering blog-post rather that to the article itself, then that simply proves that you are merely hair-splitting as regards formal academic reporting conventions, for want of being able to actually refute the substance of the argument itself. That says it all! What say *YE*, Sir?
As to your other points, see my post for Harvey here: https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-578123.
Hi Harvey,
…You say that
“I have suggested thermal conduction (of the sun’s heat) through a thick (non-porous) crust rich with PAHs which are as thermally conductive as metal.”
Could you provide some *a reference* for the high thermal conductivity of PAHs? I’ve looked but not found one. Metallic thermal conduction is largely electron mediated. PAHs do not have metallic electrical conduction….
I know you want references, but I will just go through the thought experiment aspect of it first. Graphene is essentially an infinitely large PAH molecule, and its thermal conductivity is far higher than metal, because the conjoined aromatic bond is very thermally conductive. Fractionation processes in the low pressure environment evaporate the smaller molecular weight PAHs and leaves the very large PAH molecules stuck together on the thick surface. Gases from below would push through, but the surface would remain a thermally conducting gunk impervious to erosion…
Hi Gerald
Re:
“Marco,
I’d like to learn more about your proposed Carnot cycle.
How is nature forced to work the opposite way it usually does? What’s the mechanisms?”
The primary source of energy, I’ve worked out is insolation. When you say “nature” biological systems are nature, and have very sophisticated energy cycles, say within living bodies, so although it is opposite to non-living natural systems, life, and the immediate antecedents to life, may have naturally occurring Carnot cycles.
So thermal energy is conducted down say 50m when the surface is insolated. The evident outgassing is evaporation from 50 metres down which keeps the thermal gradient when sun facing.
When the surface is in shadow, the water vapour condenses and freezes on to the pores that were outgassing them, evident in both the visible water ice cycle and the “turning off” of the outgassing. The thermal gradient reverses as the surface cools, but at the interface between the crust and the bubbly water “mud”, the water freezes, becoming insulating (igloo style). This allows the conducting layer to cool, insulated from the warm interior it was warming.
The Oxygen ratio may or may not be problematic to this Carnot cycle scenario, but the suggestion of “Gaia” has already been made, as well as the suggestion of biota being responsible for the Oxygen. The pieces fit in reasonably well without a multiplicity of potentially contradicting primordial formation parameters.
Hi Marco,
maybe I’ve missed something, but I don’t see a working Carnot cycle here.
The thermally conductive layer looks like essentially neglectible regarding the temperature of the “wet mud”.
It “just” protects the proposed water from escaping.
Below, the mud is exposed to thermal cycling. In the long run, we get a temperature of the mud close to the planetary equlibrium temperature, the mean of which is well below the freezing temperature of water. The proposed liquid water would hence freeze in the long run, or ice would never melt below some depth, assuming ices as initial state.
Just the surface layer would undergo seasonal and diurnal thermal cycling, roughly the same way as it would close below the surface without the proposed conductive PAH layer.
Hi Gerald,
Yes. There is certainly more to it.
Incidentally, the equilibrium temperature should be expected to be far higher than “tens of Kelvin” but yes, also far lower than 300K if we are looking at it in terms of the planetary equilibrium temperature.
I do tend to look at it in terms of energy flow to the interior until all the water has been liquefied, and after that, homeostasis is maintained by outgassing – ie energy lost to the latent heat of the vapour is gained from thermal energy that makes its way in to the nucleus.
My assumption is that we are not looking at anything near an “initial state”. I am hypothesising that the interior of the nucleus is currently in the order of 300K and 30 millibar, and has water as a major constituent and is very porous making an internal atmosphere subject to convection. The latent heat associated with billions of tonnes of water would take a lot of cold soaks to freeze again.
The process to get to complete melting may have involved little to no outgassing whatsoever. Thus “comets” in that process may look like class D asteroids, such as the Halloween asteroid.
And yes, this would possibly include long period comets.
But getting to the Carnot cycle – the Carnot cycle may not even be operating in an energy capturing way.. I can see a number of ways that heat can be “pumped” to the core, just from Goldilocks material properties making a natural reverse cycle air conditioner, but I do not see the necessity of it happening now, when the core is already melted.
Hi Marco,
ok, so take Jupiter’s moon Kallisto with a mean surface temperature of about 134 K as a reference for the comet since 1959:
https://de.wikipedia.org/wiki/Kallisto_(Mond)
Before 1840 the distance to the Sun has probably been much larger.
Heat takes 1000s of years, if not longer to migrate to the deep interior. So for the core temperature this more distant past is relevant. Therefore the few 10s of K.
But ok, assume 134 K mean surface temperature.
Usually the interior will approximate this temperature with time by thermal conduction:
https://en.wikipedia.org/wiki/Heat_equation
That’s far below the freezing point of water.
Which mechanism can overcome this?
We’d need at least 200K to get some brines liquid.
Hi Marco,
you might try some greenhouse effect. But I doubt, that this works, since the comet is almost dark grey over all relevant wavelengths.
You may postulate the existence of a greenhouse effect. But this would be a mere existence conjecture without evidence.
I just mention it, to be fair. But I’ve no idea how to underpin it with observational data.
The only way would have been MUPUS. But I think, it would have shown either the contrary, or only a small greenhouse effect.
Hi Gerald,
My main issue with engaging with you in regards to mechanisms to heat the core is that I don’t accept the premises (or axioms) with regards to the narrative of cometary history. Bibring often recites the history of comets as being pristine remnants from the cold reaches of the early solar system, then says “But we are not too sure about this”
The premise that I have, that over the last few million years, that 67P has gone from a much larger body, has had several episodes of orbit that goes inside the orbit of Venus, has had paths that are perturbed by the planets, without hitting the planets and so forth – are hard to reconcile with conventional axioms to come to reasonable conclusions given the same observations, and the same accepted physics.
The current scientific paradigms are under a reasonable amount of stress with most new discoveries being unexpected and challenging – such as the discovery of O2, but plenty of others.
As far as the original question goes, with how O2 is outgassed when there is no reasonable way to store it at high temperatures, I retract my hypotheses that it could be in the gas and dissolved in liquid water. The quantities do not add up as you have described. For it to be consistent with a warm liquid H2O bubbly mud interior, the O2 can only be the result of biota with radically different chemical pathways than photosynthetic sources of O2. I have a link to the study of such bacteria in extreme Earth environments, so I do think it reasonable if liquid water were evident, at any rate.
Hi Marco,
well, there may exist lithotrophic bacteria, which may be more active under warmer conditions.
From a very superficial point of view, this would coincide with the comet being more active near perihelion.
But without evidence of abundant aqueous alteration, and without evidence of abundant organic molecules with specific biochemical properties, this is more fiction than science.
A cold interior with frozen volatiles is so much easier to fit to observations.
The O2 emanations rule out some formation models, particularly those involving much of the inner solar system. But I don’t see the Whipple approach as being fundamentally challenged. Well, the dust/ice ratio needs to be adjusted for each comet individually, as well as the possible region where the comet could have formed.
So we see significant refinements of the initial idea.
But Whipple couldn’t know this lot of new detail.
67P is particularily dusty.
Hi Gerald,
Regarding comment on O2 thread:
“Hi Marco,
well, there may exist lithotrophic bacteria, which may be more active under warmer conditions.
From a very superficial point of view, this would coincide with the comet being more active near perihelion.
But without evidence of abundant aqueous alteration, and without evidence of abundant organic molecules with specific biochemical properties, this is more fiction than science.
A cold interior with frozen volatiles is so much easier to fit to observations.
The O2 emanations rule out some formation models, particularly those involving much of the inner solar system. But I don’t see the Whipple approach as being fundamentally challenged. Well, the dust/ice ratio needs to be adjusted for each comet individually, as well as the possible region where the comet could have formed.
So we see significant refinements of the initial idea.
But Whipple couldn’t know this lot of new detail.
67P is particularily dusty.”
I don’t perceive refinements at all. Every failure of the initial idea to predict new facts has been “hindcast” into the model, with the unverifiability of formation scenarios providing unchallengeable saving hypotheses. Thus a dark organic (to take the first paradigm threatening example) coating has gone from being a surprise unexpected observation in 1986, to being “predicted by the Whipple model” in subsequent cometary probes. Similarly for jets, unpredicted compounds detected by Stardust, bilobed shapes, dry surface, temperatures outside the range predicted, and so forth. Formation hypotheses that “save” the hypothesis of primordial material of comets may well contradict other formation hypotheses proposed to explain other detail unexpected by any initial formation hypothesis. For instance one detail of 67P may suggest formation in the deep dark cold recesses, while other detail may imply formation far closer to the sun.
Far better to go with “We are not too sure about this” quoting Bibring, and toy with some other, science consistent paradigms, to see if they are less “surprised”, less reliant on initial pristine conditions, more predictive.
When it comes to “evidence of abundant organic molecules with specific biochemical properties”, I go back to what may or may not have been discovered in Stardust. Together with the verified Glycene, many other biologically relevant compounds were found. These were so biologically relevant that they were classed as Earthly contamination. I read the passages which explained the process of deciding whether they were contamination or not. Basically, without any evidence that any protocol was breached that may have contaminated the aerogel, all the biologically relevant evidence was discarded.
Hi Marco,
before claiming the discovery of amino acids, you first need to verify, that it’s not a contamination.
Glycine is the most simple stable amino acid.
Carbamic acid (https://en.wikipedia.org/wiki/Carbamic_acid) is unstable.
For biologically meaningful peptides, you need more than one amino acid. If there would exist abundant proteins, e.g. within bacteria, other amino acids would be present, too.
And not in some random way, but accompanied with other biologically meaningful compounds, e.g. nucleic acids, needed to encode peptides.
You need the translation, or at least replication mechanisms, i.e. either something like a ribosome, or in the more simpler way some appropriate nucleotides, or in the most simple way, ingrediants for a polymerase chain reaction (PCR,
https://en.wikipedia.org/wiki/Polymerase_chain_reaction).
The biochemically difficult part is the polymerase (https://en.wikipedia.org/wiki/DNA_polymerase).
Fragments of it would show up in chemial analysis.
If you compare this complexity to glycine (https://en.wikipedia.org/wiki/Glycine), you may note the big gap between biology/biochemistry, and actual findings at comets.
The best we can hope for, are very early precursors needed for abiogenesis (https://en.wikipedia.org/wiki/Abiogenesis).
… when findings are too similar to microbes on Earth, it’s suspect, too, and cannot easily claimed to be of extraterrestrial origin.
Probes built on Earth usually aren’t entirely free of contamination. Knowing the details of this contamination, is crucial for interpretations of later analysis results.
Only finds definitively not interpretable as contaminations from Earth meet the criteria of a discovery.
(keyword: round trip contamination)
“Every failure of the initial idea to predict new facts has been “hindcast” into the model, with the unverifiability of formation scenarios providing unchallengeable saving hypotheses. Thus a dark organic (to take the first paradigm threatening example) coating has gone from being a surprise unexpected observation in 1986, to being “predicted by the Whipple model” in subsequent cometary probes. Similarly for jets, unpredicted compounds detected by Stardust, bilobed shapes, dry surface, temperatures outside the range predicted, and so forth. ”
Indeed, Marco. I couldn’t have put it better myself… (except perhaps to add: the double flash observed on Tempel 1 when the Deep Impact impactor slammed into it in 2005, at least 3 violent short-lived large-diameter outbursts on 67P with attendant intrinsic brightness at the base of the ‘jets’ for which the mission teams are presumably still trying to “understand the data”, or the strange ‘music’ attributed to coma/solar ‘wind’ plasma activity, among many other utterly unexpected *observations*).
Reassuringly, there now seem to be several of us on the board who are pointing out the paradigm-saving tactics you depict, despite our coming from extremely different places and clearly getting quite different sorts of intellectual and/or ‘citizen-scientist’ kicks from doing so.
This issue scaled quickly.
Of course Scientists could be going in wrong directions [as referring to what We know and suspect today]. Deliberately going in wrong directions. But directions that can be tested against ROSETTA’s Scientific frame.
Doing other way would yield low results -positive or negative-. And issues would remain speculative, until new mission designs provide necessary [organic chemistry] framing.
“Origanljohn
What always intrigues me about your posts is you utter certainty that you are right & everyone else wrong. […] It is frequently apparent that you have no understanding at all of the mathematical & numerical aspects, yet you feel able to make ‘ex-cathedra’ statements about what is going on.”
Harvey, it is not Originaljohn but yourself who are using the ex-cathedra “argument” (even if it is true you have dropped the “Professor Rutt” title over the past few months…). The rest of us are happy to just use real arguments based simply on 1/empirical observations of what is happening in the universe, 2/correct application of the principles of “real physics and chemistry” (to use your own expression), and 3/rigorous logic. This is what I take to be the “scientific method”. Everyone, whatever their scientific leanings, claims it as their own but unfortunately it is never actually applied whenever inconvenient observations come to falsify the original theory… again and again and again…. This has repeatedly been the case with the standard ‘dirty snowball’ comet theory, with the successive waves of “unexpected”, “surprising” or “mysterious” images and data which have been sent back by Rosetta over the past 15 months. The theory can only be saved, repeatedly, by the stubborn repetition of mere underlying ASSUMPTIONS such as the existence of sublimating sub-surface ice. Sub-surface ice has never been observed and the assumption of its very existence has now just been made totally redundant by the discovery that the hydroxyl and water molecules observed in the coma are NECESSARY products of the abundant oxygen seen to be pouring off the surface, to immediately react with the equally abundant hydrogen in the solar “wind”.
The 67P laboratory-in-the-sky, with its naturally free behaviour patterns and its unbridled agenda, is teaching all of us an abundance of extremely interesting things about the workings of the cosmos which cannot possibly have been observed and cannot possibly be replicated in your own necessarily regulated manmade laboratory. Comets like Chury will always behave as they see fit and will never agree to conform to your dictates.
If you refuse to take account of this obvious truth, you will simply confirm the similarity you increasingly bear to the highly eminent, deeply learned and impeccably reputed members of the early 17th century astronomy and ecclesiastical establishments who refused to look through Galileo’s telescope. Their misplaced certainties presumably also proceeded from an absolute faith in the validity of the type of ex-cathedra argument which you are yourself still using, four centuries later. It’s now a different epoch at a later date, in which people like yourself have fabricated and managed to impose the increasingly challenged “settled science” doctrine which is simply the modern-day equivalent of 17th century geocentrism and its attendant epicycles. But fundamentally, the cognitive fallacy inherent in any perceived need to resort to the ex-cathedra argument in lieu of real scientific method, in a last-ditch attempt to maintain the status quo, is still as ineffective today as it ultimately turned out to be in Galileo’s time. In terms of paradigm-shifts, 67P’s recently averred abundant oxygen and the soon-to-be-disclosed extremely high temperatures and plasma activity in the “jets” will be seen retrospectively to have played the same role in the shift from a gravity-only to an electrically-powered universe as Jupiter’s moons did a few centuries ago in the shift from a geocentric to a heliocentric universe. The importance of the 67P findings cannot be overstated: it can be confidently predicted that they will be even more of a “game-changer” in the history of astronomy than Matt Taylor initially believed when he used this expression to comment on the earliest Rosetta findings, over 15 months ago now. He could hardly have anticipated just how right he was going to be…
THOMAS,
nice how you begin with citing rules common in science, just to utterly violate them in the rest of your comment.
How? Please explain. Throw-away lines just won’t cut it, Gerald.
THOMAS: “the discovery that the hydroxyl and water molecules observed in the coma are NECESSARY products of the abundant oxygen seen to be pouring off the surface, to immediately react with the equally abundant hydrogen in the solar “wind”.”
Could you please point to the paper describing the “discovery” that water is “necessarily” a product “of the abundant oxygen seen to be pouring off the surface”?
And to a paper showing that hydrogen is “equally abundant in the solar “wind”” as the oxygen “pouring off the surface”?
I choose to omit the title because I don’t use in in everyday conversation, & don’t wish to appear to ‘pull rank’ by using it all the time here. Neither do I use the post-nominal letters I’m entitled to, other than in a business context.
It was included in one or two early posts, & I think once by mistake in a cut & paste.
However there are secondary reasons for preferring not to use it, & I would be grateful if you would do me the courtesy of sticking to the name I choose to use here, as everyone else does.
As I said, I & other professional scientists are continuously reviewed for our competence in many ways; not least by consultancy customers. What ‘quality control’ do you apply?
The *only* ‘assumption’ is that textbook basic physics applies; conservation laws for example; unfortunately your knowledge of it is too limited for you to understand that you break them in virtually every post you make.
I couldn’t care less whether Whipple was right or wrong, or whether there is or is not ice under the surface. And there is much that neither I, nor I suspect at this moment anyone else, understands about the genesis of & mechanisms operating on the comet. What I dislike is pseudo science of the type we see here all the time; explanations which are simply ridiculous if you have any understanding at all of the underlying science.
(Incidentally, many of the individual processes operating can be observed perfectly well in the lab – photoionisation, charge exchange etc etc; but not of course the large scale phenomena.)
Wow! I’ve been trying to post responses to people for 4 days now, without realizing that the CAPTCHA function now only works at the bottom of the page….
So this one is for Gerald, who says:
“Originialjohn,
your post
https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-574611
is false from beginning to end.”
Please spell out your refutation by all means, Gerald, taking account of these new oxygen findings if possible. Without which, your empty statement will simply be taken as such by everyone except the standard theory faithful like yourself. You are hardly doing your side any sort any sort of service by this sort of comment.
This is comical Thomas.
Your support for originaljohn is a contradiction of your own version of events.
You can’t have it both ways.
Please explain where the contradiction resides.
THOMAS, The new oxygen findings are interesting. They tell something about the early origins of the comet in the interstellar medium.
Molecular oxygen in the interstellar medium is difficult to observe from Earth. So the comet provides new information which would otherwise be difficult to access.
That’s simply exciting. This great yield hasn’t been expected. So, it’s “surprising” in the positive sense. The instrument scientists deserve to be proud and happy..
@ Gerald
“The instrument scientists deserve to be proud and happy.”
I couldn’t agree with you more, Gerald! I’ve always made it clear that I have much greater admiration for the engineers and technicians who have made this whole thing happen, with the extraordinary observations they are providing, than for the theorists who are putting forward over-hasty conjectures founded on a very long series of questionable assumptions.
It is precisely the observations acquired by the former which will ultimately lead to the falsification of the theories elaborated by the latter. In short, I feel hugely grateful towards the former…
Why then, THOMAS, do you (and Originaljohn) explain close to everything by z-pinches, before knowing the data?
Just as a parody of some – in your eyes – over-zealous theorists?
What Gerald? Really? You acknowledge the difficulty of observing oxygen in the interstellar medium, without acknowledging why that might be. Then you suggest that the presence of oxygen in a cloud around the comet nucleus may somehow relate back to the origin of the solar system, implying rather strongly that free oxygen simply evolved from the comet having somehow managed to survive as free oxygen for billions of years. A new form of inert oxygen eh.
The reason you skated over the difficulty of observation is that oxygen is strongly electronegative, one of the most electronegative elements, with only two electrons required to complete its outer shell. It rarely therefore survives in the free state for any length of time without reacting with something. The idea then that it could exist in the free state for your billions of years as part of a comet nucleus then all of a sudden or even periodically evolve into a cloud around the nucleus is absurd. As unlikely as to be impossible in fact.
Far more likely, that with unknown origin it would remain bound and inertly trapped in the rock of the comet nucleus for an unknown period of time until it encountered periodically an input of sufficient energy to break its bond to silicon and release it.
Obviously the free oxygen is produced at the comet nucleus in the short term and obviously in such profuse quantity that despite the intimate presence of an abundance of reactive hydrocarbons and the energy to initiate the reaction, enough oxygen remains unreacted for a long enough time for it to be detected by the Rosetta instruments.
It is indeed a crushingly devastating ( as THOMAS has coined it above) effect ( blow) for the primordial comet theory. Objectively it kills it stone dead. Not only that it absolutely confirms that oxygen is being produced ( freed) at the comet nucleus. Good stuff. Keep it coming.
Well, Originaljohn, you are right, that atomic oxygen is very reactive. In this case, it reacted with other oxygen atoms, to form O2.
O2 isn’t the same as oxygen in statu nascence. In O2, the two missing electrons are partially filled by the electrons of the other oxygen atom, such that we get a double bond:
“In this dioxygen, the two oxygen atoms are chemically bonded to each other. The bond can be variously described based on level of theory, but is reasonably and simply described as a covalent double bond that results from the filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atoms, the filling of which results in a bond order of two.”
(https://en.wikipedia.org/wiki/Oxygen#Properties_and_molecular_structure)
Without activation energy, as ice, how should O2 react? Or “bound” in a clathrate hydrate, why should the oxygen react with water at very low temperatures?
“the energy to initiate the reaction”: No, the energy to sublimate O2 at below -200°C is insufficient to initiate “the reaction”.
“…The idea then that it could exist in the free state for your billions of years as part of a comet nucleus then all of a sudden or even periodically evolve into a cloud around the nucleus is absurd.”
Pause is the ‘default’ state of mater. Why not?
Hi OriginalJohn: “… A new form of inert oxygen eh. ” Not discarding ACTUAL electro-chemistry.
But as for initial grain formation We are talking of hardly double digit temperatures. We are talking of another -snap on kind of- chemistry.
And authors are suggesting a preference, within the [reduced] Universe of Solutions ROSETTA allows for testing.
They do not present ‘biological’ options just because they can’t. Would be pure speculation. Knowledge empty.
This one’s for ianw16, who, in his meaasge of 08/11/2015 at 21:24, mentions “…areas where the WATER PRODUCTION (AND THEREFORE O2 PRODUCTION) is lowest… » (my capitals for emphasis)
No Ian, you’ve got it the wrong way round: in case you haven’t yet realized, the findings of the May 2015 Astronomy & Astrophysics article which you are presumably alluding to (“Measurements of the near-nucleus coma of comet 67P/Churyumov-Gerasimenko with the Alice far-ultraviolet spectrograph on Rosetta”), which hypothesized “an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface” by UV photodissociation, have just been superseded (as I understand it) by the findings of “very abundant molecular oxygen” spewing directly from the comet surface, as reported in the blog-post at the head of this thread.
Quite contrary to what you affirm, it is thus actually a case of “O2 PRODUCTION (AND THEREFORE WATER PRODUCTION)”.
Please tell us if you believe that this averred inversion of the causality you invoke has no incidence on your conclusions, and if so why.
BTW, your concluding, never-supported reference to “something we already know, and have evidence for; that comets have ice beneath their surfaces, and that it sublimates” just doesn’t cut any ice whatever any more with anyone able to apply rigorous logic to actual observations, for the reasons I’ve just given. Your so-called “evidence” was never anything more than a set of unsupported ASSUMPTIONS, as has just at last been demonstrated by the new findings. The hydroxyl and water detected in the coma are produced by a series of oxygen + hydrogen reactions. This is REQUIRED by the most basic laws of real physics and real chemistry, as has constantly been pointed out by EU proponents for decades now.
What’s that, THOMAS?
Electric universe dadaism with some shouting capital letters mixed in to pretend importance?
Well, water can form from hydrogen and oxygen.
But which “most basic laws of real physics and real chemistry” dictate, that this must take place in a deeply frozen comet, where it cannot take place by exactly those “most basic laws of real physics and real chemistry”?
How can oxygen and plants on Earth coexist according to your nice try of logic?
Thomas wrote,
“The hydroxyl and water detected in the coma are produced by a series of oxygen + hydrogen reactions. This is REQUIRED by the most basic laws of real physics and real chemistry, as has constantly been pointed out by EU proponents for decades now.”
Why don’t you the provide the chemical equations for this “O2 + protons in solar wind gives H2O reaction”, particularly when it involves highly ionized intermediate O species and “is REQUIRED by the basic laws of real physics and real chemistry.”
The reality is you don’t know and this is nothing more than an exercise in hand waving.
Even we assume that such a reaction was possible, the fairly constant O2/H2O ratio completely and utterly contradicts it.
Since jet activity “comes and goes”, O2 is used up to produce H2O in a finite period of time.
The concentrations of O2 and H2O will decrease and increase respectively in that time frame until the reaction ceases, hence the O2/H2O ratio will decrease with time.
The fact that the O2/H2O ratio is constant indicates no such reaction occurs and is dependant on the emission of each gas from the nucleus.
Thomas
The problem is:
“causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface” by UV photodissociation, have just been superseded (as I understand it) by the findings of “very abundant molecular oxygen” spewing directly from the comet surface, ”
No, you don’t understand it.
You cannot readily form O2 from two O1 at low pressure; you cannot readily form H2O from O2, O, H or energetic H+ at low pressure.
You can readily produce O, OH etc from H2O by photodissociation.
You *probably* can produce O from O2 by photodissociation.
There are aspects of the two measurement which need to be checked for consistency; but they are not in immediate & obvious conflict as you suggest, neither does one supplant the other.
This one’s for Harvey, again, in answer to his
11/11/2015 at 07:38 post:
@Harvey
I quote from the abstract of the Astronomy & Astrophysics article on the Alice findings:
“The Alice far-ultraviolet spectrograph onboard Rosetta is designed to observe emissions from various atomic and MOLECULAR species from within the coma of comet 67P/Churyumov-Gerasimenko”.
Are we therefore to understand that Alice detected O1 atoms but failed to detect the apparently much more abundant 02 molecules? Or were the authors also “in denial” of the O2 molecules they had in fact detected (or alternatively had no explanation for …)? Or might there have been some sort of sharing agreement between the ALICE and ROSINA teams to define who announced what? In my view, the problem of how to reconcile the findings of these two articles to make something useful of them clearly persists. (Quite apart from the fact that the origin of the detected oxygen, whatever its chemical form, is seen in both articles to be a matter of pure conjecture, based on unproven assumptions).
You can hardly claim there is no problem here…
ALICE is a UV instrument covering 70-205nm
It detects the emission lines of atomic oxygen, O1 (O Roman numeral one). That says *nothing* about its ability to detect O2 (O subscript Arabic figure 2; molecular oxygen.)
Atoms produce discrete lines from electronic states.
Molecules produce complex ro-vibrational bands which tends to spread the intensity out. There is also the question of the relative absolute intensities of the bands (which I don’t know.)
The O2 Schumann-Runge B-X system does indeed just overlap the long wavelength end of the ALICE range, extending to maybe 175nm. But you need to look at – and understand – some nice things called Franck Condon factors, & know what vibrational levels your source molecule is in, to determine whether ALICE could see it or not.
It cannot see molecular oxygen in its electronic ground state other than in absorption; interesting question is whether ALICE could make an absorption measurement using the sun as a source? Probably not.
There is no direct, simple-minded ‘conflict’ between these measurements. There is a need to look at the two data sets & check for consistency. One measures apples; the other oranges; but they are both measuring whats happening in the fruit basket.
@Sovereign Slave
“Just wanted to say, Thomas, you’ve laid out some scorching posts here. Can almost smell the singed eyebrows. Nicely done. I guess no answers to your posts (that I’ve seen at least) is sometimes the most revealing answer.”
CAPTCHA still isn’t working for the individual “Reply” links, so here’s another “bottom of the page” post…
Thanks, Sovereign Slave. There have since been one or two responses on minor points, as you’ve no doubt seen, but it’s true that in the main these latest findings seem to have left the standard theory defenders decidedly groggy since they are literally inexplicable in mainstream terms… It’s Chury that’s doing all the work, though, not me! I feel a bit like a striker being fed inch-perfect passes in front of an open goal. Can’t wait for the upcoming temperature and plasma data, even if it’s a long time coming, (of which, for example, the abstract of the “In-situ investigations of the ionosphere of comet 67P” article presented at the 2015 European Planetary Science Congress recently gave us some tantalizing hints of:
https://meetingorganizer.copernicus.org/EPSC2015/EPSC2015-656.pdf ), to slam in the final “game-changing” goals (to quote Matt Taylor’s famous expression)….
@Thomas,
“…..to slam in the final “game-changing” goals (to quote Matt Taylor’s famous expression)….”
Really, that is hilarious! Considering you’re 10-0 down with no striker on the field!
In other words, EU have zero evidence for any of their claims at this or any other comet, and there is a shed load against it.
The abstract for the meeting you quote has nothing in it for EU proponents. Not those that understand what electron temperatures are, anyway. This has already been pointed out previously.
Perhaps you can tell us when you, or anybody else, is going to submit the evidence for all these daft claims to a respected scientific journal? Failing that, you are no further on than you have ever been; zero evidence, and clogging up comments sections of blogs and pop-sci websites with crazy ideas. Taken no more seriously by the scientific community than is homeopathy or astrology.
Whew!
As Bruno Mars sings, it’s “Too hot! Call the Police and Firemen!”
@ Harvey
Many thanks for the limerick (https://blogs.esa.int/rosetta/2015/10/28/first-detection-of-molecular-oxygen-at-a-comet/#comment-577049). I honestly believe it’s a very useful form of expression since the rigorous demands imposed by this verse-form require the writer to convey distilled meaning in very few words, a bit like a Shakespearian sonnet or, in a different culture, with Racine’s masterly use of the alexandrine in French neoclassical literature. Every single word counts, and in this respect (although each author is entirely responsible for his own work), I believe that your first line contains an oversight: I began myself by “There was a *young* comet named Chury” because this is precisely the claim made by EU comet theory. I suggest that you should have replaced “young” by “old” in your own first line “That sylph-like young comet called Chury”, since this is an *objective expectation* of the standard theory – at least 4.6 billion years old (and apparently even older, if the latest mainstream attempts to explain away the abundant, newly-found molecular oxygen are taken into account). I’ve never equated old ducks with sylphs either, but there we’re getting into the realm of mere subjective perception and everyone is obviously free to feel whatever they want.
Here’s another one, in which I sum up what I take to be the game-changing chemical reaction which, logically, has just been discovered on Chury:
When oxygen’s born on wild Chury
Its lifetime is short and quite gory.
To wed it is fated,
By force it is mated
With H, to sporn water… what glory!
And another, on the academic process whereby the news was ultimately revealed and on the conclusions which might be drawn from it to guide future research:
With O2 found pouring off Chury,
The experts reacted unsurely.
They longed to deny
It was there, and then why.
But it’s there, on all comets like Chury!
I look forward to reading your own next offering.
Young as a short period comet; old as a long period object; its a Limerick, who cares.
If you only would apply –
instead of simply deny –
poetry to reality,
I would like to see.
You can do, don’t be shy.
Not bad for a first try at a very demanding verse-form, Gerald. It doesn’t scan, but I’m sure you can quickly improve by following the guidelins in the Wiki article on limericks: https://en.wikipedia.org/wiki/Limerick_%28poetry%29
So, given the frequent rather ill tempered exchanges, let me make my position clear.
I’m a professional scientist/engineer; but I’m *not* in any way involved in comet science, or indeed any other astronomy. But I do have knowledge of a great deal of related science and technology. I don’t have anything ‘invested in’ any particular comet model; it wouldn’t cause me any grief if conventional views were proved wrong; it would in fact be fascinating, rather fun.
So ‘contrarian’ view are great; fascinating; *PROVIDING* they fit the ‘basic laws of physics’, and the observed evidence.
What’s a ‘basic law of physics’? Well in a sense there are none – unlike religion. Everything is always up for grabs, valid just as long as the evidence supports it. You want to overturn, say, charge conservation? Absolutely fine; but given the huge weight of evidence in its favour, you’d better have pretty darn convincing evidence you are right and conservation of charge is wrong. If you have that, it’s no longer a law of physics, your new ‘law’ is; until it’s overturned.
But there are a number of such basic ‘laws’ which one expects to operate in any explanation of what’s going on around 67P; the conservation laws for example. There is also a large body of experimental evidence, much of it from laboratory measurements, on things like photo dissociation, charge exchange, photoionisation cross sections etc etc.
The problem is this stuff is complicated. If you can’t do vector calculus, are not comfortable with things like cross sections, big and small numbers etc etc, it’s hard to understand. The comet environment is very counter intuitive in many ways; much earth origin ‘common sense’ and experience just does not apply. Just calling yourself ‘citizen scientist’ doesn’t magically replace the years of training and experience it takes to become a ‘real’ scientist. I wonder if ‘citizen scientists’ would be happy with the services of a ‘citizen’ dentist, doctor, surgeon should they need one? I suspect not!
Now most people who don’t have that background understand the limits of their own understanding. So they might ask ‘there are these two papers, both measuring oxygen, which seem to disagree, could you explain?’ ‘Yup, sure, no problem; one measures atomic oxygen, the other molecular oxygen. The first can’t originate from the comet itself, it’s formed in the coma; the second is difficult to form in space, it very probably originates from the comet itself; but there could be some linkage between the two, however no reason they should ‘agree’; you are comparing apples and oranges.’
But that’s not what we get, based on a total lack of understanding of the material, it’s presented as evidence of a serious discrepancy. Similarly, based on a total misunderstanding of the law of electromagnetic induction, it’s presented as an explanation of how the fictional discharges are powered, etc etc.
The people concerned simply don’t understand the limitations of their own understanding of the underlying physics and chemistry. NOT ‘comet physics’, nothing to do with cosmology, the origins of the solar system, whatever, just absolutely basic ‘physics101’. And I reiterate, that *can* be overturned too; but not by specious arguments starting from no understanding of the ‘law’ in question. So, time and again, we just get what can only be called ‘nonsense’ – the politest word I can think of for it. Arguments which are simply risible if you actually do know the underlying basic physics – and have the evidence that you know it.
Yes, sometimes people in a field get too attached to a particular theory. Yes, the existing theories are unable to explain everything going on on 67P (great! – more interesting!). But those facts are *NOT* evidence in support of ‘theories’ breaking basic laws, in obvious contradiction to observation – when you actually understand the observation – which have no quantitative or analytical content whatever; they are evidence real physics needs to do better; which is why we sent Rosetta to 67P .
I wouldn’t equalize citizen science with “electric universe” nonsense.
There are several fields of research which wouldn’t work well without citizen scientists – just think of observations by the amateur astronomer community, of faunistic and floristic observations, or “the dusters” screening the aerogel of the Stardust mission:
https://stardustathome.ssl.berkeley.edu/
But I’m unaware of anything useful contributed by the “electric universe”.
They just claim themselves being citizen scientists. That’s as misleading as other “electric universe” claims.
@ Harvey
“We are getting quite a lot of ‘reasoning’ along these lines, from Thomas, but from others too:
“Since the hydroxyl/water detected in comet comas is thus seen to be the result of a continuous, large-scale oxygen + hydrogen reaction, …….”
May I set the record straight here: I take no responsibility for what others are claiming, but my OWN argument is rather that since no oxygen has ever been detected in the coma of any comet, either by ground-based facilities or by space probes during fly-bys, the inescapable conclusion is that as it moves away from the surface of the nucleus, it must NECESSARILY be reacting with something to produce something else; and by far the most likely candidate is clearly hydrogen to produce water, particularly in view of very close relationship proved by the more or less constant 02/H2O ratio observed by ROSINA. Despite your objections to this most ‘obvious’ schoolboy chemistry solution, I suspect you would be hard pressed to suggest any better alternative. You can’t escape the conclusion that something drastic is certainly and very rapidly happening to ALL the oxygen molecules pouring of the surface of comets…
When you then go on to concede “I can see why this might seem ‘natural’” before objecting “but unfortunately it relies on an ‘earth bound’ image of chemical reactions; it’s *very* different in the comet environment”, I’d like to know what enables you to make this “very different in the comet environment” distinction. In fact, I’ve noticed that you tend to change your position on this particular issue (the similarity on not between the comet environment and earth-bound conditions) to suit the argument you’re putting forward – a classic case of ‘goalpost shifting’ …. When, for example, it comes, in contrario, to the idea of comets being the focus of an electrical pinching of the solar “wind”, you deny outright the very possibility that anything might be happening which is different from what is experienced on Earth, as if a comet could be akin to a terrestrial body such as an aeroplane flying through a terrestrial wind, with no electromagnetic interaction taking place between the object and its medium. It is precisely in THIS particular case that the earth-bound comparison totally breaks down, since the expression “solar wind” is utterly misleading and just shows how little the astrophysicists who originally coined this term knew at the time about the electromagnetic properties of the stream of plasma radiating from the Sun. We now know a lot more about the Sun’s own electrical properties which determine the charged nature of the solar “wind” plasma, but we are unfortunately now saddled with this total misnomer which is having lasting effects on the mental representations even of astrophysicists, let alone the layman. It is precisely these electromagnetic properties of comets, via their exchanges with the plasma of the solar “wind”, which are now being spectacularly demonstrated by the behaviour of 67P, as has been observed in close-up by ROSETTA for over a year now through the spectacular discharge activity which also bears a misnomer in the form of the term “jets”.
To summarize, I believe that the essential defining characteristic of a comet is precisely its electrical reaction with the solar “wind”, and that it is this unique phenomenon (unique to comets as opposed to objects on more or less circular orbits around the Sun, which therefore possess little or no charge difference with respect to the Sun) which, through the literally incalculable effects it necessarily has on the yet ill-defined make-up of the comet’s surface, accounts for possibly different chemical reaction chains from those commonly obseved on Earth to produce the observed water from the averred oxygen and hydrogen. It is no doubt not simplistic, “schoolboy” chemistry, but so what? You can hardly claim that the relevant reactions, whatever they are, are not happening since the results are there: not a trace of oxygen ever detected in the outer comas of comets, despite the abundant oxygen spewing off their nuclei (being the “fourth most abundant gas” detected by ROSINA)… Please tell us how YOU account for this, if only in general terms (you don’t necessarily have to propose the precise, detailed reaction chain).
Thomas:
I’d like to know what enables you to make this “very different in the comet environment” distinction.
Its explained in the previous post; pressure & collision rates. These totally change ‘what chemistry happens’.
So let me be a bit more specific.
Look at Fig 1 in
https://www.dtic.mil/dtic/tr/fulltext/u2/a264896.pdf
Below 0.4mmHg (about 52Pa – & lower than I expected) there is *NO* mixture of H2 & O2 which will ignite. This is the most favorable case, a pure H2/O2 mixture, which has an extremely wide flammability range at 1 bar of about 4 to 94%.
Why? The processes involved are:
H2 =2H (1)
H + 02= OH + 0 (2)
0 + H2 =OH + H (3)
OH+H2=H+H20 (4)
H+H+M=H2+M (5)
0+0+M=02+M (6)
H+O+M=OH+M (7)
H+OH+ M=H20+M (8)
(From https://www.dtic.mil/dtic/tr/fulltext/u2/a264896.pdf)
These all depend on collisions; note that reactions giving a *single* product, 5-8, involve an ‘inert partner’ ‘M’ (which could be any species – but it doesn’t ‘react’) needed to conserve energy & momentum. Now collision rates vary linearly with pressure, & so (say) radiative energy loss etc has more time to operate, & the three body collisions of type 5-8 become very rare.
At low pressure, chemistry is just *very* different.
More anecdotally, its often claimed La Paz in Bolivia has no fire brigade, because no fires burn at that altitude, with an air pressure very roughly 40% lower. *it is not in fact true*! – but what is true is that at altitudes of 4-5000m camp fires are hard to ignite & keep going, due to the reduced pressure (I know, I’ve climbed to over 6000m.)
So burning hydrocarbons in a *FAR* lower pressure in oxygen diluted in water vapor, carbon dioxide etc, is most certainly NOT going to happen.
Incidentally Thomas I don’t expect evidence & data to change *your* views, but it might interest others.
Sure, no doubt on Earth, Harvey. But what about on comets, where you yourself claim that everything is so totally “different” that we can no longer reason in earthling terms with respect to the acquired observational data.
I say it again, *you can’t eat your cake and have it* (to quote a saying which is nearly always *misquoted* by inversion of the salient terms and which is thus also, in a totally different domain, a too-frequent victim of automatic, logically-challenged “thinking”)…
THOMAS: “Sure, no doubt on Earth, Harvey. But what about on comets…?”
That’s what Harvey explained:
“At low pressure, chemistry is just *very* different…”
Your auto-reply is completely mis-placed here.
It applies, instead, to your own preceeding comment.
@ Gerald
And by its selective quotation of what I was saying, your answer carefully and conveniently evades the point I was making. It would be nice if you actually addressed the issue I’m raising here .
THOMAS, what’s your issue?
When packing too much of rhetoric into your comments, it’s hard to tell, whether there is actually something you’re trying to say.
If it’s about the difficulty to detect molecular oxygen from a distance, just try to distinguish oxygen from nitrogen, when looking into an empty glass.
The molecular oxygen near the comet is very dilute. Any attempt to detect it from Earth needs to distinguish those small amounts from abundant oxygen in Earth’s atmosphere.
Once the oxygen near the comet is ionized – and easier to detect – you cannot easily say, whether its origin is water or molecular oxygen.
… the presence of ionized oxygen in the coma of comets is well-known since decades:
https://articles.adsabs.harvard.edu//full/1981A%26A…103..154F/0000154.000.html
“The forbidden oxygen lines … have been formally identified in a high resolution spectrum of comet Mrkos (1957V) by Swings and Greenstein (1958)”.
“A very large set of observations of te forbidden lines of O1 is presented by Swings (1962).”
So THOMAS, your statement “…not a trace of oxygen ever detected in the outer comas of comets..” is wrong. It’s unclear, whether you’re simply ignorant of the facts, or whether you’re intentionally ignoring or confusing the facts to create a false basis for your reasoning.
Please explain.
Or aren’t you aware of the difference between molecular and atomic oxygen, THOMAS?
Do you ever actually read or think about replies?
That’s exactly the point; the environment of the comet is a low pressure, low collision rate environment.
That’s exactly why the ‘chemistry’ is totally different to ‘1 bar 300K’.
In fact we can readily reproduce such conditions in the lab to check much of this. But it follows from laws as basic as conservation of energy & momentum.
Thomas wrote,
“To summarize, I believe that the essential defining characteristic of a comet is precisely its electrical reaction with the solar “wind”, and that it is this unique phenomenon (unique to comets as opposed to objects on more or less circular orbits around the Sun, which therefore possess little or no charge difference with respect to the Sun)…….”
Absolute rubbish.
Solutions to a gravity inverse square force law give rise to conic section solutions where an orbit can have an eccentricities from 0 (circular) to infinity (hyperbola).
Comets follow Kepler’s laws of planetary motion irrespective of the eccentricity of the orbit assuming there are no gravitational perturbation effects from planets.
If your so called electrical effects perturbed the orbit of the comet, Rosetta would never have reached its target as the calculations are “gravity only”.
Please explain this “electrical reaction” involving solar wind pinching given that the comet does not even have a magnetic field let alone a varying one to induce a current in the solar wind and create pinching through Lorentz forces.
My position has not shifted in the slightest in terms of the rationale applied.
The conditions at and around 67P are wildly different to those most people are used to, and common sense extrapolation of earth bound experience readily gives wildly wrong answers.
However that does not mean ‘anything goes’.
The fundamental ‘laws’ of physics apply around 67P just like anywhere else. Indeed that is often why what happens in that environment is so different.
But those laws also completely preclude the ‘electrical’ nonsense which is in obvious conflict not only with conservation laws, but observed data.
The problem is indeed neatly summarised in the opening sentence of your final paragraph. “Insummary, *I believe*…..’ (Emphasis added.) that’s the problem; it’s a belief, it has no basis in science whatever.
The current evidence suggests that molecular oxygen is degassing from the comet, water undergoing photolysis etc as expected. Electronic ground state molecular oxygen is difficult to detect remotely; I muse in another post on that possibility.
There is an interesting detailed issue regarding photolysis of the molecular oxygen and whether the effects of that are observable; it might be, see my other post. It might have been missed because molecular oxygen wasn’t expected or modelled, and at 5% of the water, you’d have to unscramble things very carefully; the O/OH ratio, and observed electronic state emissions recorded by ALICE, might give some clues.
Where the oxygen came from and how it survived etc I don’t consider myself competent to comment on. I restrict my comments to things I know about and understand.
Gerald, something does occur to me regarding putting your statistical probability math powers to work. What’s the probability that two large comets could smash into each other at just the right speed and angle to create a contact binary, as reflected in the ESA video. Given that they ran into each other at just the right orientation as to sheer away close to half of them (instead of completely obliterating them), and they had to be the exact right density to allow this to happen, and slowing them down enough for their gravity to bring them back together, and for there to be no spin created by the collision for either comet. A million to one seems highly optimistic. And if this is supposed to explain all the other two lobed comets and asteroids, it becomes even more unlikely. And if it doesn’t explain the others, what does, and why can’t it also explain P67? Yet now contact binary is the officially accepted explanation, but what are the odds?
Sovereign Slave,
all your points look reasonable and need a satisfying answer.
My knowledge is limited, so all I can do is providing a partial answer, not quite free of opinion.
First some opinion: As far as I see, the simulations done so far are preliminary, and are likely to undergo several steps of refinement. I wouldn’t take them too literally, despite all the efforts already comprised. It’s good work, but probably not yet completed.
My partial answers:
Q: “What’s the probability that two large comets could smash into each other at just the right speed and angle to create a contact binary, as reflected in the ESA video.”
A: It’s impossible to provide absolute numbers. Instead, you need to consider a framework of initial conditions, where you may estimate probabilities. This can be done by Monte Carlo methods:
https://en.wikipedia.org/wiki/Monte_Carlo_method
The other basic principle needed to be considered is conditional probability:
https://en.wikipedia.org/wiki/Conditional_probability
For 67P, and other comets, this means, that only outcomes with an observable comet as a result should be counted, since observations are biased towards, or even constrained, to these outcomes.
Initial conditions comprise velocity vectors of the components as well as their material properties.
Velocity vectors in disk of debris around a celestial object, for comets probably the protoplanetary disk around a young star (for 67P the young Sun), tend to adjust to each other by “friction”.
This “friction” comprises drag by gases and collisions.
“Inside the Roche limit, orbiting material disperses and forms rings whereas outside the limit material tends to coalesce.”
https://en.wikipedia.org/wiki/Roche_limit
The Roche limit is rather close to the central object, for the Sun and cometary material maybe a few diameters of the Sun.
The Kuiper belt region is far outside the Roche limit. The material that far out therefor tends to coalesce (by the gravity of this material).
This coalescence progresses the faster the denser the rings of debris are.
This coalescence (accretion) can start not before relative velocities are sufficiently low to allow gravity to overcome velocity.
For comets, this means, that the relative velocities need to be near the respective escape velocity.
We get hence near about 1 m/s for local relative velocities, when comets of 67P type start to form at all.
The framework within which probabilities for contact binaries make sense should therefore constrain local relative velocities to a few m/s.
Models of planetary disks may be run, starting with these conditions, and observing the stability of these velocity assumptions.
The resulting local relative velocity distribution would then provide refined reasonable assumptions.
Just colliding two bodies with arbitrary random velocities doesn’t reflect the conditions of comet formation scenarios.
Material properties aren’t exactly known. But starting simulations with rough grains of dust would be reasonable, considering the GIADA data.
The properties of the pristine ice isn’t exactly known. But assuming silicate grains with an ice mantle would be reasonable, since ices tend to nucleate on dust grains.
The ice mantle may be of different shape, like needles, or more like fractal snow crystals. There may also exist shattered crystals from collisions, which later re-accreted to snowflake like structures.
These initial grains are rough, and they accrete to very porous “fluffs”.
Now, when colliding two cometary nuclei, this fluffy structure should be considered.
It leads particularly to a low compressive strength, and to high plasticity. This is in contrast to most hydrodynamical models which assume incompressible spheres as grains.
Collisions between comet nuclei hence tend to behave more like the collision of two snow flakes rather than like the collision of two billard balls.
This means, that they tend to adhere, instead of bouncing back.
Now run the Monte Carlo simulations with this framework to get (model) probabilities of contact binaries.
Q: “Given that they ran into each other at just the right orientation as to sheer away close to half of them (instead of completely obliterating them), and they had to be the exact right density to allow this to happen, and slowing them down enough for their gravity to bring them back together, and for there to be no spin created by the collision for either comet.”
A: Here you need to differ between arbitrary contact binaries as an outcome, and a binary similar to 67P.
The probability for arbitrary contact binary formation is much higher than the formation of exactly 67P.
The small spin change is due to the chosen material properties of the rubble pile. A model material with small tensile strength and few friction with respect to inertia doesn’t allow for much exchange of angular momentum by collision.
The angular momentum with respect to the center of mass of the two bodies remains conserved during and after the collision.
Completely obliterated outcomes wouldn’t be observed as a comet today, but we need to constrain to observable comets.
“A million to one seems highly optimistic.”: Depends on the probability distribution of the initial conditions. Assuming arbitrary conditions is certainly not realistic. Constraining the conditions to scenarios, where comets form at all, improve the probability for contact binaries.
“And if this is supposed to explain all the other two lobed comets and asteroids, it becomes even more unlikely.”
You know, that for asteroids, YORP is still a player.
Two lobed objects may also form due to rotation imposed by a rotating accretion disk forming the object. This would btw. be a catch-all scenario you’re looking for. But reality is more complex.
“Yet now contact binary is the officially accepted explanation…”: At the moment. This will either be confirmed by more and more evidence, or eventually replaced by a better solution.
Remembering stunts ‘landing’ on piles of empty boxes. Visual allegory.
Good question.
Its not clear one can do a real calculation, because you would have to make a huge number of assumptions about the density of objects with a given size, velocity distribution etc etc.
But its the intuitive improbability that always made me lean to an ‘erosive’ origin for the shape – & I believe Gerald did too.
The ‘contact binary’ paper makes a persuasive case in many ways, but some stab at this sort of analysis is certainly needed – may already exist? Need to check that paper’s references.
Harvey and Gerald, thanks again for the replies. Difficult to capture solid answers figuring probabilities obviously. I do notice though that it seems that the simulations apparently assume a great deal of “working” knowledge of how the solar system formed for base line input, which could be pretty problematic for obvious reasons. If the scientists were bored enough, seems one approach would be to simply shoot two very scaled down “comets” at each other in a lab over and over using a high speed camera, different speeds, angles/approaches, densities, materials, etc. Would like to know if they could ever make them cut each other in half like the simulation shows, which just seems beyond belief. Simulations much less messy though.
SS
Unfortunately gravity is far too weak a force to have any effect on an in-lab simulation like that. But its effect is crucial.
In some areas, like aerodynamics, you can legitimately do scale model measurements, by keeping things like the Reynold’s number the same.
But I don’t think any scale model experiment is meaningful for an interaction involving gravity.
(The electrostatic force has the same functional dependence, but of course charge will transfer in the collision, & I’ve no idea if you could get the scaled forces right; it would seem very difficult – the computational ‘experiment’ is probably better.)
Well, I guess that’s the rub, simulations that are completely unprovable and unfalsifiable should really not be presented as evidence of anything at all, and the contact binary theory is completely far fetched to begin with, and in my mind, the simulation even makes it more so. What makes this science trustworthy?
Sovereign Slave,
on Earth you can’t do the microgravity experiments.
The other issue is the material properties.
Once you know them, you can either simulate them or do physical experiments.
But for a fully realistic physical experiment you would need to actually collide two km-sized cometesimals in outer space.
That’s certainly beyond the budget of a lab.
Feasible within the budget are small experiments with”comet analog” material, and scaling them up within computer models. The laws of gravity are very accurately known; so that’s not the problem in realistic simulations.
To a substantial degree I agree with you.
In some circumstances, where the physics and material properties etc are really well known, a simulation can I think validly support a hypothetical explanation where direct experiment is not possible. But even here I’d regard it with caution.
But it’s clear that here is there a lot of very, very complex physics which may not be fully modelled, material properties poorly known, and a lot of queries about velocity and mass distributions of the colliding objects.
So I’d regard the simulations as a fairly weakly supporting bit of ‘evidence’ at best, of a qualitatively different kind.
In short, I’m not ‘sold on’ contact be nary as yet.
Fortunately gravity is such a weak force, otherwise each of us would be crushed flat against the surface of the Earth, unable to take a single step, unable to breathe, dead in fact. Now the electromagnetic force, there’s a different kettle of fish.
Indeed; but we don’t notice it much; for pretty much the same reasons comets don’t notice it.
We aren’t (significantly) charged, aren’t in high electric or magnetic fields, and are pretty high resistivity.
Sure the EM force is strong; its highly relevant to the tenuous plasma around the comet; irrelevant to the large scale material removing processes.
I may get ruled ‘off topic’, but I think these have interesting relevance to disagreements here 🙂
https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect#cite_note-13
https://www.brainyquote.com/quotes/quotes/c/confucius101037.html
The 2000 Ig Nobel Prize Winners
The 2000 Ig Nobel Prizes were awarded on Thursday night, October 5th, 2000 at the 10th First Annual Ig Nobel Prize Ceremony……………………
PSYCHOLOGY: David Dunning of Cornell University and Justin Kruger of the University of Illinois, for their modest report, “Unskilled and Unaware of It: How Difficulties in Recognizing One’s Own Incompetence Lead to Inflated Self-Assessments.” [Published in the Journal of Personality and Social Psychology, vol. 77, no. 6, December 1999, pp. 1121-34.]
Touché from Harvey 🙂
Feeling myself more like Unskilled but Unwilling to fill my mind with data, -the same way a quick millionaire fill his quick library. Having the one-in-a-lifetime-privilege of Minds like Gerald’s&Harvey’s&OtherSouls’ in this Endeavor 🙂
Oh please, Logan, I’m experiencing my own limitations almost every day, multiple times.
The mind is confined to a small short-lived skull on a small planet around some average of billions of stars in some average of billions of galaxies in some small niche we call the observable universe of a universe we don’t know much of anything, which is again….
Don’t expect too much of it.
The privilege is to get a glimpse of it at all, while knocking at the very finite confining skull all the time, and struggling with exogenic inconveniences of our mere fragile physical existence.
🙂 “a glimpse”….
OK reCAPTCHA, you win, again 🙂
Logan – can I say that comment was not intended for you; you have always been politely explicit about areas where your knowledge is limited.
It’s OK Harvey 🙂 Anyway, don’t like cleaned, beautified blogs. Those feel unreal.
Gerald, Ianw – anyone doing real science 🙂
I’m travelling and don’t have my usual academic access, or books to hand. And as we are on holiday if I spend too long on this I’ll be in trouble with my wife 🙂
I was musing on whether the effects of the O2 ought to be discernible in other ways.
Not at all thought through and no access to references; and molecular spectroscopy of electronically excited states isn’t so much my thing.
One possibility might be emission from the Schumann Runge system, B-X, in the region where it has line structure, 170-200nm ish. It’s probably too weak, and if the molecular oxygen gets fully dissociated well away from the nucleus, probably not observable close in due to dust scatter?
I did find some tentative observations just using Google, but nothing convincing.
But how about photo dissociation of the O2? Just above threshold you will just get invisible ground state O. But higher, you will get potentially observable electronically excited emission? Maybe from Lyman alpha excitation? Possibly in different states to O from photolysis of H2O? Also, if I recall correctly photolysis of water mainly produces H and OH with little O. Would the presence of ~5% molecular oxygen be detectable against the species produced by water photo dissociation, cause a discrepancy in the observed O/OH maybe.
(Molecular oxygen has no infrared signature of course.)
Basically, any thoughts on whether the molecular oxygen can be, maybe should have been, seen by other spectroscopic measurements?
Harvey, without look-up I can say, that the K-alpha line by exitation of atomic oxygen would be “surprising”.
This technique is “widely” applied in planetary exploration.
Usually some transuranic nuclide is used to excite target atoms by alpha particle or x-ray emmisions of the decaying nuclide.
The sensor then measures the x-ray emissions of the target. The first K-alpha lines you get are those of sodium, since a K-electron is removed, and replaced by an L-electron. This is obviously possible only for elements starting with ordinal number 11 (sodium).
You get, however, another effect: That’s scattering, Rayleigh scattering as well as Compton scattering. Rayleigh scattering shows up by some widening of higher-energy x-rays. Compton scattering results in more or less typical Voigt / pseudo-Voigt distributed x-ray energies.
The distributions of these scattered x-rays can be used to infere the presence of elements lighter than sodium.
Although I doubt, that someone has tried to apply or adjust this method to x-ray emissions in astronomy.
https://www.researchgate.net/publication/257021018_Refinement_of_the_ComptonRayleigh_scatter_ratio_method_for_use_on_the_Mars_Science_Laboratory_alpha_particle_X-ray_spectrometer
Any x ray attempt to distinguish O2 from O atomic would require very good x ray resolution surely?
Chandra (https://chandra.harvard.edu/about/science_instruments.html)
LETG (https://chandra.harvard.edu/about/science_instruments.html) in-flight calibration (https://cxc.harvard.edu/cal/docs/cal_present_status.html)
showed an error of 0.006 to 0.01 Angstrom.
The oxygen K-alpha line is near 530 eV, corresponding to about 2.34 nm (https://halas.rice.edu/conversions), or 23.4 Angstrom.
The relative error is hence about 4.27e-4, corresponding to 0.23 eV for 530 eV.
This is sufficiently accurate to narrow down K-alpha emission/absorption for oxygen bound as metal oxides:
https://www.fzu.cz/~kunes/papers/kur.pdf
Thanks. So you could indeed distinguish them that way.
If I’d thought a bit longer, having occasionally used XPS, I should have known that myself!
O2 is a difficult target remotely, whichever way you try.
… but I guess, any attempt to infere molecuar oxygen from x-ray spectra would take very long integration times.
… I thought, observations of oxygen lines have been classified as “water” in a more general sense, without actually pinning down the source species.
Observation of neutral O2 possibly difficult from a distance.
I remember remote CH4 measurements on Mars were difficult due to CH4 in Earth atmosphere; could be similar with O2.
… just some (limited) brain storming …
Ok, silly idea; is there any way the 55-65GHz magnetic dipole transition could be observed, or might have been observed?
The background is low, you are below the black body 2.4K peak.
It would have to be from space of course; I think the high altitude mm wave receivers would still be wiped out by atmospheric absorption.
WMAP had a channel sitting right on it, 61GHz, 21 arc minute, but PLANCK straddled it. Of course the angular resolution is awful due to the 5mm wavelength, and the comet would be a small fraction of the resolution, greatly reducing the signal.
But I wonder if a comet ever happened to cross the view of the 61GHz channel of WMAP? Not likely to put it (very) mildly, but with the fantastic sensitivity of that instrument, just maybe it would have been observable.
As I said, rather wild idea. I think a dedicated measurement might well be possible, but it’s probably too ‘narrow’ to be a fundable concept.
Gerald, Ianw, etc, too crazy for you? 🙂
Some kind of extremely focused laser resonance? Active scanning?
Sending a nano-second signature? Expecting a signature the following seconds, or minutes?
Absorption spectra might help. Again issues with Earth’s atmosphere. Better with space probe.
The only molecular oxygen absorption band that looks any use is Schumann-Runge around 175-200nm. But absorption is always hard; you need a source – the sun I guess. Its not ‘background free’, you are subject to source fluctuations (at a minimum, photon Poisson statistics) & it constrains the geometry badly.
Also molecular bands ‘spread the intensity out’.
Remote O2 is *tough*.
Gaia determines the spectrum of each observed star.
Comparing the spectrum of the same star with and without the comet might reveal absorption lines of the coma.
https://blogs.esa.int/rosetta/2015/11/03/cometwatch-from-gaia/
“they will also use Gaia’s photometric observations of these comets to investigate their composition and surface properties.”
Unfortunately the 175-200nm are outside the spectral coverage of Gaia photometers:
https://www.hindawi.com/journals/aa/2010/781421/fig1/
… but Fraunhofer lines A, B, Y, Z, attributed to O2 in this Wikipedia article
https://en.wikipedia.org/wiki/Fraunhofer_lines#Naming
would be covered.
But maybe a glitch in Wikipedia.
Gerald see:
https://www.nist.gov/data/PDFfiles/jpcrd8.pdf
which I finally managed to get a look at (still travelling. Took forever to download.)
Section 3, page 430.
But I still have limited access & can’t search properly & cant read all that on the small screen!
I’m not clear these Fraunhofer lines are really O2; that may really just mean ‘oxygen’ in Wiki, ie potentially O(Roman numwral follows.). If it really is O2 I think its an atmospheric band which is electric dipole forbidden & seen because of the high pressure-path product – & it should be a *band*, not a *line*.
This is all known for sure, just cant get at it easily right now; indeed it may well be all in that ref.
Harvy, thanks!
I didn’t read all the detail. But it appears, that it should be possible to infer pressure, chemical composition, isotopic composition, and ionization from the spectra.
The difficulty is certainly distinguishing oxygen of the upper Earth atmosphere from the oxygen near the comet. Since Earth’s exosphere is “hot”, the widening of the lines might provide a clue, but possibly also relative intensities.
Certanly difficult. So it’s not a big surprise, that Earth-bound observations, or other remote observations didn’t see molecular oxygen at comets.
… Other sources, e.g.
“Stars and Their Spectra: An Introduction to the Spectral Sequence”, p.71,,
or
https://www.daviddarling.info/encyclopedia/F/Fraunhofer_line.html
say also
7594, 6867 Angstrom: “terrestrial oxygen (O2)”, resp.
“A band O2 (molecular oxygen in Earth’s atmosphere) 7594–7621
B band O2 (molecular oxygen in Earth’s atmosphere) 6867–6884”
Ah, just seen this, thanks.
Cant get the links, hotel wifi 🙁
Almost certainly weak electric dipole forbidden lines in O2 then; but you need the massive pressure-path product of something like earth’s atmosphere to see them.
… Noise/fluctuations of the difference spectra can be beaten down by stacking a sufficiently large number of samples.
Spectral characteristics of stars may change sufficiently slowly in some cases, such that before and after occultation spectra can be interpolated.
I guess, that SOFIA’s HIPO instrument should be well-suited for this kind of investigations:
https://www.sofia.usra.edu/Science/instruments/HIPO-SPIEs/2004SPIE.5492..592.pdf
Overview paper oxygen transitions, as of 1972:
https://www.nist.gov/data/PDFfiles/jpcrd8.pdf
Backgound possibly fluctuating (cosmic dust, other radio sources).
But subtracting background may nevertheless reveal moving foreground object (comet).
My knowledge about radioastronomy is too rudimentary to decide, whether the idea is crazy or doable.
Back-of-an envelope calculation would be needed to compare foreground signal strength with background fluctuations, to infere feasible S/N.
Yet another idea:
Velocity distributions of O+, O, and O2 differ.
This results in different peak shapes due to Doppler shift.
Built over a fast, trans-Jupiterian vessel 😉
All of this is fiction.
We need a basic understanding of logic here.
Given a finite theory, its consequences are usually infinite, and no one knows them all. When someone says that we do not understand gravity, that is true for the same trivial reason that we do not understand electricity, or that we do not understand quantum mechanics, or that we do not understand human beings. We usually use a theory to say that it explains this fact and that fact, and explains many facts in a limited subject area pretty well.
Scientific theories are incomplete: we may neither be able to deduce a particular consequence nor its negation. It might take an awfully long time even with the fastest computers to check whether a particular fact is a consequence of a theory. When your nose is runny you don’t go to doctors and ask them whether this is a consequence of the fact that you now have pneumonia.
When people on this blog say that the discovery of a new fact falsifies an existing theory, or that “scientists” should now tell them how the theory explains the new fact, they are mostly wrong. When people talk about “mainstream” science, they are talking about the combination of some
theories which together explain many facts which we know about many different subjects without contradicting each other. It is far from the case that mainstream science can explain everything. Here is my belief: if your theory can explain everything, then you have a religion.
Going to a comet does not confirm any existing theory. The idea is to discover new facts and see which theories will extend to explain those facts. Most often an existing theory may not have said anything which makes the new fact true or false. What did medical theories say about a new virus before it was discovered?
Extending the theory to explain the new fact is difficult because one has to not lose the facts about that subject that the theory did explain, and now one has to explain this new fact in addition. Different extensions may be possible. Your runny nose may be due to several infections. The doctor suggests tests to decide on which possibility is more likely. With an astronomical object the number of tests one can do is small and quite often zero.
To complicate things further, modern theories talk about facts being true with some probability. Human beings find reasoning about probabilities hard and sometimes counter-intuitive.
Galileo (confirming Copernicus’s prior theory) turned out to be right.
Re Kamal – basic understanging of logic
Nice artical Kamal, but on the comet we seem to be finding gaps, so whether a completely new theory or just an additional theory, to explain the gaps, it does not matter, but it would be nice if there was one or the other to settle some of the disputed ground.
We seem to be struggling to come to terms with some of the surprises at the moment.
regards
Some very nice points, Kamal. Highlights the fact that theories are never complete, and are never a completely accurate representation of “reality.” I think I’ve read through most of the comments on this post, though lots keep getting added. One thing I notice is that the article seems to make clear that there has been a significant and very surprising discovery about oxygen output on P67 that’s potentially something of a game changer. But in all the back and forth of the posts, this new discovery starts getting normalized to the point where it’s like, well, move along, nothing to see here. Also obvious that to the defenders of the mainstream, this can’t have anything to do with electrical causation. In fact, it illustrates the fact that nothing discovered will ever be considered to support EU. As many have pointed out, everything about EU is nonsense and woo, and every mainstream knee is triggered to jerk in reaction against it, no matter what is or isn’t found – it will always be nominalized as discoveries are normalized within mainstream beliefs. Even if the jets are found to be superheated, so to speak, I really don’t think it will matter, even far fetched explanations serve to normalize the abnormal.
Hi SS,
I do admit to having an open mind. There is absolutely no basis in EU for any grain of truth however. It basically tramples over the most basic assumption of uniformitarianism applied to physics and chemistry, of all things. Gravitational, electrical, chemical laws are well known, and are applicable.
It matters little that conventional science hasn’t been predicting things that it should, like O2, it is the narrative that is dubious, not the laws of gravitation and electricity.
No matter how wrong the current paradigm ends up being, there is no way EU will be the next one.
Sovereign Slave,
there exist conditions with changing high magnetic fields, or with high voltages out there. But not near the comet, far away from the Sun and large planets.
So, all this z-pinch stuff applies very weakly, at most, several orders of magnitude off to explain any visible effects.
If traditional convictions turn out to be inconsistent with measurements, it’s a lot more likely, that an entirely new approach succeeds, than “electric comet” ideas, since the latter are “utterly” inconsistent with observations in too many aspects (magnetic and electric fields, including electromagnetic radiation, proton flux, conservation laws, etc.), and they are too poorly elaborated for an option to be useful.
SS,
Rather than stereotyping the 3 or 4 individuals that regularly debunk EU here as defenders of the mainstream faith, perhaps you should find out what motivates each person.
My background is applied mathematics and as such I don’t have a vested interest in the mainstream view.
I support the mainstream view because IN ITS CURRENT STATE OF EVOLUTION it is largely supported by observation and experiment.
A piece of information that has came out this report is the O2/H2O ratio averages 3.8%.
Did EU “theory” predict this result?
No it didn’t, yet the flood of posts that has come from the resident EU supporters would suggest otherwise.
How is a fairly constant O2/H2O ratio consistent with the EU idea that O2 reacts with the SW to form H2O? Well there is no consistency.
Hence the EU posts claiming validity on this result is basically nothing but noise.
Does pointing out this noise constitute a defence of “mainstream belief”.
No it doesn’t.
In fact the term “mainstream belief” is an oxymoron used by individuals who do not understand how science operates.
Ironically the mainstreamers are those that administer this site.
Yet despite the fact these mainstreamers are non too subtly portrayed as incompetent, dishonest, arrogant, dogmatic etc by EU supporters and others, they allow such posts to flourish.
Hardly a kneejerk mainstream reaction.
Dave, SS: In my view the electric theorists are being impractical by trying to do a completely new theory, it would be the work of centuries. So one has to say I give up these-and-these parts of current science and I agree to retain these, and then build a theory from there. If you say I want to start from Galileo on mechanics but I want Maxwell for electromagnetism, that is too many centuries apart and too much work for any one to figure out exactly where you stand on several questions, and I would then believe you are talking through your hat.
The work of centuries ??
Hardly!
Small parts of a century saw the development of QM, QED, the ‘standard model’, nuclear physics, etc etc.
Science moves a bit quicker now than it once did.
A new theory based on sound basic science could develop in a a handful of years at most.
Who cares how many centuries separate them? We use the relevant approximations; when and where they arose is irrelevant.
Hi karmal, re EU completely new theory.
I am really just a very curious observer, I always have been.
The EU seems to start way before Galileo, with inspiration coming from ancient astronomers maybe 7k years or more ago. These ancient drgs and depictions seem to resemble plasma forms, and strangely many of the observations seem also to tell the same story of the classical gods all round the globe.
This is of course a fantasia at the moment mainly because its difficult to interogate correctly, but the observations are clearly real.
Its possible the EU have the wrong end of the stick, there are other explantions of the ancient drgs.
So you are right it is a big task for them, and its probably best to find something that can be easily modeled and supported by experiment and the requisite maths physics and chemistry, so that the door can be opened a little.
However the surprises that arise in projects like 67p, Pluto and Ceres seem to tax the settled scientific community (which is good, its how we learn), but too often the mainstream appears to be quick to dash new ideas but slow to explain what is happening, too keen to just trot out old cliches, with out really examining what is happening ( this is how it appears, of course much work is being done behind the scenes).
So for a curious observer its very entertaining, and few of us on the blog can afford to think that we have the answer.
regards
Thomas: No, you are wrong. Copernicus’s theory extended more easily to the moons of Jupiter.
SS: Re: No one will ever support EU
As I said above, that is because EU starts from so far away, implicitly considering the work of several centuries of scientists as nonsense. I would then believe that it is EU that is nonsense.
Thomas made a smart point about whether Alice discovered something which could be interpreted as a signature of O2, and you can see later discussion on such a possibility, as to whether one can discover a second observational fact which will tell us something more about O2.
No Kamal, Thomas did not make a ‘smart point.’
He fundamentally misunderstood the fact that ALICE measures one thing and the mass spectrometer another, that those two species have different origins, and that the connection between an ability to measure O and O2 is not straightforward. Their spectroscopy is utterly different both qualitatively and quantitatively.
It’s necessary to understand the data before making meaningful comments on it.
There *are* issues to resolve around whether any subtle inconsistency exists; but it’s not a simple minded in your face discrepancy by any means, as was claimed.
The issue revolves around photo dissociation of O2 producing O, and to what extent this introduces issues with O from photo dissociated water; as there is some twenty five times more water, it’s the unclear if the perturbation from the O2 would be noticeable or not, and that may be position dependent due to differing cross sections and energy dependence of the processes. These processes were never mentioned.
In contrast in was claimed the O2 was ‘obviously’ reacting with solar wind protons, which for a multitude of reasons is a non starter.
“..this new discovery starts getting normalized to the point where it’s like, well, move along, nothing to see here.”
Lots to see here. Such a high point in the geography, that we are looking far, far back 🙂
Is not that We are ignoring ROSINA’s Team news. Is that we are hooked at them. Unwilling to leave the forte.
Some interesting responses, some true to form, others not so much, which is always refreshing. Though Marco, I think you should maybe rethink your mindset. To first state that you’re open minded in one sentence, then in the very next sentence to say there’s absolutely a grain of truth in something because it doesn’t line up with other established assumptions tends to discredit your first statement. And while there are some laws or principles that are well known regarding gravity, electricity, and chemistry, I think it’s safe to say that there are still vast amounts of things about them that are not known. And that goes at least double for when they take place in space. Case in point, what seems to be happening with the oxygen presented in this article. And regarding electricity, how many experiments have been done with electricity in space to determine how it really behaves in that environment, or what it looks like, or how it interacts with matter, or how it travels, or the different forms and shapes and characteristics it might take. And who knows what its true scale could be, or pervasiveness, or even how it might be recognized? Even on earth, electricity as it manifests in nature is not well understood, much less in space. Or take all the countless studies that have been done on health and the human body, yet understanding about electricity and it’s role in our own bodies is still very limited, and bioelectromagnetics could probably still be considered an infant science, something which cosmology could be said to have in common.
Without the necessary electrical experiments in space (the vast majority of which are no doubt not feasible), everyone (EU and “mainstream” – sorry sjastro) is pretty much reduced to educated guess work based on very limited data and observation and whatever earthbound “laws” might seem to apply. And yes, for better or worse, EU has a completely different take on cosmology (sleek in it’s proposition of basically one unifying force, which is appealing in it’s simplicity, and oh, they don’t constantly try to fit new data into some kind of creation mythology, which is much appreciated), and though it has some huge obstacles to overcome, so does mainstream (apologies again, sjastro) cosmology.
But as you say, mainstream cosmology is the current state of evolution. However, it’s a simple fact that there’s another evolution taking place in which a growing number of (misguided, no doubt) scientists and academics are seriously looking at and investigating EU. And if that trend continues, EU heresy may become more and more difficult to dismiss out of hand.
Oh, and btw, I don’t assume a lack of intelligence or competence or integrity on the part of the ESA scientists, anything but. But I also recognize that most of the science being done is far far removed from the checks and balances of the lab (though Philae was a brilliant field lab, alas), and should therefore be subject to the most rigorous of skepticism.
Finally, Gerald, I believe I’m correct in interpreting what you posted as indicating that you more or less agree that there are electrical conditions that exist that are somewhat in line with what EU proposes, but these are orders of magnitudes too weak or far away to have significant affects on the comet. So here’s my question…if these electrical conditions, such as z-pinch etc etc, WERE strong and near enough, in what ways would they potentially affect the comet and it’s activities?
To Marco, sorry, NOT a grain of truth…
Hi SS,
In short, I am not so open minded that my brain falls out. The idea that the laws “are necessarily different in space” tramples on the axiom of uniformitarianism. There is absolutely no basis for challenging this axiom on say Coulomb’s law or gravitational laws etc. the list is long.
Without uniformitarianism being correct (enough at the scale of our solar system and beyond), probes would all fail at the point where supposedly the laws “are different in space”
There is huge scope for the mainstream to be wrong, but only on what it cannot hope to measure directly. For instance, I have promulgated theories that involve the interior of the comet to have a radically different thermal profile to that of the mainstream thought. I look for indirect evidence that this is so. Indirect evidence involves value judgements, but there is a lot (such as surface morphology) which is, in my view, very indicative of the radically different internal thermal profile that an am suggesting.
Things like “electric field” and surface temperature are measured directly. EU gets close to questioning the measurements rather than their interpretation to perhaps unknown processes (as opposed to physics not acting uniformally in space as on Earth)
In short, EU tramples on uniformitarianism, and doesn’t seem to acknowledge the need for self consistency in a mathematical, or even logical sense.
You wrote,
“Without the necessary electrical experiments in space (the vast majority of which are no doubt not feasible), everyone (EU and “mainstream” – sorry sjastro) is pretty much reduced to educated guess work based on very limited data and observation and whatever earthbound “laws” might seem to apply. And yes, for better or worse, EU has a completely different take on cosmology (sleek in it’s proposition of basically one unifying force, which is appealing in it’s simplicity, and oh, they don’t constantly try to fit new data into some kind of creation mythology, which is much appreciated), and though it has some huge obstacles to overcome, so does mainstream (apologies again, sjastro) cosmology.”
First of all lets clear up some confusion here. Is this supposed to be a discussion on Cosmology, Planetary Science or both? Unless you think Planetary Science is a branch of Cosmology which it clearly isn’t.
Big Bang Cosmology (assuming this is your creation mythology reference) is NOT a theory about the creation of the Universe.
It is a theory about the evolution of the Universe.
It does not extend back to the cosmological time t=0, the supposed Big Bang event.
One way of understanding this is to take an object of mass M and shrink it.
At what stage does the object go from being described by classical physics to quantum mechanics.
This occurs when the object size reaches it Compton wavelength.
https://en.wikipedia.org/wiki/Compton_wavelength
Similarly for the Universe, the “cosmological version” of the Compton wavelength is the Planck length. Below this value the very early Universe was quantum mechanical in nature. This length is not only beyond the range of resolution of any instrument, but is theoretically impossible to define due to the uncertainty principle.
Hence our knowledge of the Universe up to the time of the Planck length is unknown.
Of course EU has a different take on Cosmology but then so does creationism.
The fact is EU is much more closely related to creationism than Science.
Have to ever seen a mathematical EU model that predicts some particular value that can be tested? Of course not. The EU mantra is that everything is explained by electricity as a divine creator is for creationism.
I can understand why EU is appealing as it is largely bereft of mathematics and physics. It appeals to the individual who either lack the skills or the compulsion of learning the maths and physics.
Unfortunately simplicity is not a prerequisite for a theory to be supported by observation and experiment.
You wrote,
“But as you say, mainstream cosmology is the current state of evolution. However, it’s a simple fact that there’s another evolution taking place in which a growing number of (misguided, no doubt) scientists and academics are seriously looking at and investigating EU. And if that trend continues, EU heresy may become more and more difficult to dismiss out of hand.”
.
Who are these scientists that are seriously looking at EU?
The only EU paper that I know of that on the surface that might appear to be of interest to mainstream is titled “Magnetic Field of Birkeland Currents” by Professor Donald Scott PhD (Electrical Engineering).
By the time I was half-way through the paper I realized the good professor should stick to electrical engineering and not plasma astrophysics.
The paper was riddled with elementary mistakes.
His mathematics was a rip off of the Lindquist solution for force free magnetic fields in plasmas which he did not even acknowledge in the references.
The maths was not even relevant as the plasmas he was describing were not force free.
The maths was provided as window dressing.
If this paper was submitted to peer review in a physics journal rather than the usual haunt such the Institute of Electrical and Electronic Engineers it would have been crucified.
Its papers like this as to why mainstream have no interest in EU.
Another interesting query from that paper.
https://electric-cosmos.org/BirkelandFields.pdf
At the end, it has a brief CV. The highest position noted is ‘Associate Prof’, & it refers to him as Dr.
I’ve not found a later or more comprehensive CV, but my search capabilities are currently limited.
Maybe he got a ‘full Prof’ post later.
Where exactly does the title ‘Prof’ derive from?
Although usage differs in different countries, normally only ‘Full’ Professors use the prenominal ‘Prof’, not ‘Associate’.
The EU crowd refer to him as “Professor” Don Scott probably as a form for exaltation, but more likely they wouldn’t know the difference.
In a similar vein there is Stephen Crothers, the EU hero and supposed mathematician who has “proven” General Relativity is wrong, Black Holes don’t exist, Big Bang Cosmology is wrong etc etc.
Yet Crothers is a failed and bitter PhD student.
https://www.sjcrothers.plasmaresources.com/PhD.html
It seems the EU crowd engages in hyperbole in describing some of its members.
This tongue in cheek description of Crothers is probably more realistic!
https://rationalwiki.org/wiki/Stephen_J._Crothers
Sovereign Slave,
the heliosphere has been investigated, e.g. by Ulysses
https://science.nasa.gov/missions/ulysses/
and by SOHO
https://www.nasa.gov/mission_pages/soho/index.html
SOHO observed about 3000 comets close to the Sun.
The problem with the Sun: In regions of high magnetic and electric activity, the solar heating is a serious problem for comets due to their volatiles.
Very close to the Sun, tidal forces may be able to disrupt comets, as we have seen near Jupiter with comet Shoemaker-Levi 9.
So, for a comet to get near the electromagnetically “interesting” zones, is a challenging task.
For lightnings hitting cometary material, there would be several possible outcomes.
“Refractory” material with low volatile abundance may melt up in the most extreme case to form fulgurites.
https://en.wikipedia.org/wiki/Fulgurite
Hitting material with abundant volatiles would cause more or less hemispherical shocks/blasts of evaporated material..
A dense atmosphere would be necessary for lightnings, e.g. cometary material entering Earth’s atmosphere during a thunderstorm.
In a larger-scale magnetic field, like near Earth’s poles, the sublimated gasses would be excited by charged particles to form an aurora, with the typical spectral characteristics for each species.
We would see it in images, if Rosetta would cross such a van-Allen belt-like structure, not just by the aurora, but also by the hits of the charged particles on the CCD chip.
The images would be heavily degraded, and the camera itself would degrade rapidly.
Such a radiation belt would, however, affect the activity of the comet only marginally, with respet to solar heat. It would just affect the appearance and the shape of the coma, or even blow away the coma.
So, long before the activity is affected, we would get obvious effects in the coma, even visible from Earth-bound observations.
The best candidates to get an idea of what would happen, are SEP events or solar flares.
https://en.wikipedia.org/wiki/Solar_energetic_particles
In a more distant future, exploitation of the presence of oxygen, and of reduced volatile species, like CH4, or partially oxidized species like CO, might open an option to distill the different species as a basis for a space station with solar heat, and exploiting the temperature gradient of the surface layers of the comet, to provide fuel and oxidizer.
In principle, some of the species could be used to grow bacteria or plants (abundant CO2), or provide a breathable atmosphere in a spacecraft, and to use the abundant water as a basis for food production.
On the basis of this kind of technology, combustion would be feasible, e.g. for propulsion.
In this context, ignition of a distilled fuel/oxidizer mix by technically generated electric sparks would be possible.
Ignition of the material, as naturally occuring, however, wouldn’t work without the enrichment technology.
…this is SciFi.
Well yes 🙂
But it is interesting that for the first time we see an ‘ easy ‘source of an oxidiser as well as a fuel.
Unfortunately the energy costs of getting to a comet and matching velocity tend to be rather high. But, at least in principle, you could go and then generate your own return fuel.
Of course we only have the example of 67P; we’ve no idea if the oxygen is a one-off, or ubiquitous, but the default assumption is that it’s ‘typical’.
Sadly I won’t be around to see such a mission; but my children or grandchildren might.
Expecting Harvey to be still around when more testing of hidden Oxygen is made. Chasing a comet could be bypassed 🙂
Harvey,
Thank you for your continued efforts to educate us on these topics. I’m a retired EE and have learned and relearned much from you posts.
Many thanks.
Regrettably I was born with an allergy to pseudoscience 🙂
Costs me a lot of time!
That should read Lundquist not Lindquist.
Evidently the Scott’s latest submission of his paper
https://www.ptep-online.com/index_files/2015/PP-41-13.PDF has found its into Progress in Physics a journal with a reputation of a dubious peer review process.
“The journal promotes individual academic freedom and will consider all work without regard to affiliations. For this reason, the articles published in Progress in Physics may not necessarily represent the scientific views of the Editorial Board or its individual members. All submissions will be forwarded to invited experts, whose professional field is close to the submission. Decision about the submission will be produced by the Editors, according to the recommendations obtained from the side of the reviewers.”
At least in this version he quotes the Lundquist solution probably because the reviewers are astute enough to detect plagiarism.
Unfortunately the errors of the original version are still there.
Fit is entertaining to examine the difference between ‘submitted’ and ‘accepted’ dates in Progress in Physics; they give a rather clear indication of their ‘refereeing’ quality.
You might also try looking up the citation rates of papers there.
The Journal is regarded as valueless by the main stream scientific community, with good reason.
I recently came across a paper there – and (literally) equation (1) was dimensionally inhimogeneous as first glance, and hence unequivocally wrong, as must be anything derived from it. No competent referee would have read past equation (1).
No one can fault the maths in paper Scott’s paper as it has been transplanted straight into the paper.
The reviewers failed to take into consideration whether the maths has any relevance to the subject matter.
Towards the end of Scott’s paper it degenerates into pareidolia science and contradicts the fact the Lorentz force is zero in a force free field.
For example Scott claims the lobes in the image of the planetary nebula M2-9 looks like a z-pinched plasma hence it must be a z-pinched plasma.
Z-pinches are due to non zero Lorentz forces hence the field cannot be force free. Also a plasma pinch increases the plasma pressure resulting in high beta values preventing the formation of force free fields.
Magnetic flux ropes that arise in force free fields are due to magnetic helicity, not z-pinches. These have been observed in the solar corona which is force free.
Then there is the evidence itself. The planetary nebula is not square to the line of sight of the observer and can be measured for Doppler shift. The current must flow through these z pinched lobes in one direction instead of ionized gas moving outwards from the central region as the mainstream model suggests.
The Doppler shift of the OIII transition lines in the lobes is either towards or away from the observer depending on the direction if Scott’s model is correct.
In fact the Doppler shift for one lobe is blue shifted, the other red shifted which is consistent with the mainstream model.
sjastro:
Re Birkeland currents, the Scott reference etc.
The math is straightforward – & anyway Bessel functions routinely appear in solutions in cylindrically symmetric coordinates.
The ‘evidence’ from Saturn etc seems to me nonsense; those structures exist well into the high pressure, unionised atmosphere & the link to any high altitude plasma structure is not made.
But the math of the Birkeland current ‘structure’, dating back to Lundquist, is as you say fine.
It raises three questions in my mind. (at least!)
Firstly there is a *very* obvious fingerprint to this structure. Has such a magnetic field structure ever been directly observed? By satellite transits through an auroral ‘rope’? By remote measurement in any way (Zeeman???)?
Secondly, I would have thought the structure might be very ‘fragile’& easily severely perturbed by anything that violates the infinite extent, uniformity etc assumptions. I think this because the total current is given by an integral to infinity over R of j sub z (and, trivially, over theta of course.) . But j sub z is the oscillating Bessel function, whose peaks decays only as r^-0.5. So getting the finite total current depends critically on the cancellation of the negative & positive regions of the Bessel function, right out to very large r. That suggests to me the elegant structure might very easily get messed up by perturbations. (This type of integral has a name which escapes me; notoriously troublesome numerically, there are special techniques for them…….’stationary phase’ methods??? From years ago!)
Thirdly, how about the kinetics? The complex structure has got to establish itself; has anyone looked at how that happens & the time constants? The fact that the mathematical solution exists does not of itself guarantee there is a route by which it can form.
You clearly know a lot more about this than I do, comments would be much appreciated.
How directly has such a structure been observed?
How stable is it?
How long does it take to ‘get organised’ – and can it do so?
Harvey,
We can use satellite data for Birkeland current activity in the Earth’s polar regions to illustrate the absurdity of Scott’s Saturn example.
https://www.tau.ac.il/~colin/courses/AtmosElec/Potemra%20ASS%20144.pdf
The detection methods are given in section 1.2.
Measurements indicate Birkeland currents enter and exit the polar regions in pairs and are not aligned into concentric, symmetrical and radially dependant structures as suggested by Scott.
If one assumes the physics is the same in the polar regions of Saturn than the observed structures have nothing to do with Birkeland currents.
The stability of magnetic fields and structures requires the of use MHD rather than Maxwell’s equations and electrodynamics.
While Scott is inadvertently describing helical magnetic fields which are as expressed in terms of Bessel functions, the formation of such structures is rather more complicated and is based on variational methods involving the Euler Lagrange equations.
As you are aware you can use the Euler Lagrange equations to show that the path taken by a bead sliding down a frictionless wire under gravity takes a minimum amount of time if the wire is in the shape of a cycloid.
Similarly the variational problem for minimising magnetic energy under the constraint of helicity conservation reproduces the equation for a force free state.
The force free field is therefore the lowest energy state that can only exist under conservation of helicity.
https://books.google.com.au/books?id=68ZVwgUr71cC&pg=PA71&lpg=PA71&dq=helicity+conservation+%22force+free%22&source=bl&ots=jcp724taWy&sig=6qfSe3j__i7I1ndUxpfHhSvdhBU&hl=en&sa=X&ved=0ahUKEwiquK-qgdDJAhWBEpQKHT5CCrUQ6AEIOzAF#v=onepage&q=helicity%20conservation%20%22force%20free%22&f=false
Don’t ask me how the variational equation was derived in the first place!!!
Force free fields have a high Magnetic Reynolds Number due to the magnetic pressure far exceeding the plasma pressure. The magnetic diffusion time scale is very slow and the magnetic field can be considered to be frozen in place in the plasma.
Coronal loops are examples of helical magnetic fields.
Interestingly the Magnetic Reynolds Number for the Earth’s magnetic field which is not force free is low and should have diffused away long ago.
It is being “replenished” by the dynamo mechanism.
Sastro – thanks, some light Christmas reading needed I fear!
Failed again!Retry
SS
You ask “So here’s my question…if these electrical conditions, such as z-pinch etc etc, WERE strong and near enough, in what ways would they potentially affect the comet and it’s activities?”
The problem with answering this is that The nature of the comet & its environment precludes a z pinch. Its a bit like asking ‘what would a fish that lived in air look like’; a contradiction in terms.
But if in some mysterious way it did exist, here are a few things………
– We would have seen obvious magnetic field evidence in the published Rosetta data; the fields would be far stronger, and show characteristic spatial patterns. This is fatal on its own.
– The (limited data seen so far) plasma results should show something strongly differing from the expected photoionised plasma; whilst some new processes were seen, the results were broadly consistent with expectations
– The discharges would be obviously self luminous, & not dependent on sunlight
– There would be a rich line emission spectrum. This would have been seen by ALICE at least, and very probably from earth for many decades.
– Most ‘discharges’ show strong transverse instability; not seen; why not?
– Most discharges show axial structure near the cathode; (we are always told its a cathode; I’ve no idea why) not seen; why not?
(The last two are not ‘fatal’; but would need a lot of explaining.)
– The thermal deposition pattern would not be expected to agree with solar radiant energy; there should be huge problems with VIRTIS data etc.
– ROSETTA would probably have been ‘fried’ by the implied particle densities; since we are never given any *quantitative* predictions, hard to be sure of that, but its certainly an issue.
– Its likely various forms of radio frequency emission would have been detected, from earth, as a source of noise on the communications channels
– Again, as we are given no quantitative prediction, hard to be sure, but if the plasma frequency of the putative discharge was high enough, it should have effects on CONSERT, Philae-Rosetta & Rosetta-earth communications, potentially blocking them. No such effects reported.
– We would see some way in which ‘the circuit is completed’. If its a’cathode’ as we are told, it supplies electrons; where do they come from? A trivial calculation shows it can’t have ‘stored enough’ (& where did t get them if it did?) so somewhere its ‘connected to an electron supply’. Where? How? Why can’t I see that?
– the comet is made of insulating or highly resistive material; all candidates are, & CONSERT confirmed that. So either I should be seeing massive surface discharges to allow current to flow over the surface from wherever/however it ‘arrives’, or there should be massive power dissipation in the comet due to resistive heating.; no such phenomena seen
And on & on & on.
The suggestion these are discharges is at complete & utter variance with a multitude of data, & at variance even with a law as simple as conservation of charge. Its based on some vague perceived visual similarity to a discharge – perceived by people with little or no experience of discharges!
Conventional science has lots of interesting thnigs to explain. It may well be wrong in some cases; it cerainly needs improvement in others; there are certainly surprises.
Great, that’s why we sent ROSETTA there!
The problems of conventional science – even if a Whipple like model is completely overturned, fine by me – do not support pseudoscientific nonsense.
BTW I should have added.
It would *NOT* be very surprising if some sort of low average power, most likely pulsed, discharge activity occurred close to the surface of 67P, though none has been reported.
‘Lightening strikes’, small surface glows, that sort of thing.
It could be driven by triboelectric effects, photoemission, even solar wind interactions at times.
I suspect any such observation would be ‘jumped on’ as proof of EU ‘theories’; no such thing.
My comments above apply to large scale discharges responsible for the major errosive provesses, the ‘jets’ etc, & do not preclude small scale discharge effects which *just might* occur.