Rosetta navigation camera (NAVCAM) image taken on 15 August 2014 at a distance of about 91 km from comet 67P/C-G.
Full-frame NAVCAM image taken on 15 August 2014 from a distance of about 91 km from comet 67P/Churyumov-Gerasimenko. Credits: ESA/Rosetta/NAVCAM
Discussion: 21 comments
Where can i find information about the timing and maneuvers during your “pyramidal orbit” . You made big media events about the large burns, but what about your 60° burns? How do you measure the precise distance to the comet? Radar? Cameras? What is your accuracy at 100km? Have the perturbations in the trajectories given you good info about the density profile of the comet? Have you had to do micro-adjustments to the paths because of such perturbations?
The Planetary Society blog has a full schedule at the end of the blog post of 15th August.
Here is the URL, if links are permitted:
https://www.planetary.org/blogs/emily-lakdawalla/2014/08150814-finding-my-way-around-cg.html
This is what the other Emily listed at the Planetary Society
Beginning on Sunday, Rosetta will transition to a slightly lower orbit, at around 80 rather than 100 kilometers, and it will spend the rest of August surveying from that altitude. Here’s a timeline of the upcoming events. Stay tuned for more great photos!
First triangular “orbit” averaging 100 km, August 6 to 17
August 6: arrival, begin first leg
August 10: begin second leg
August 13: begin third leg
August 17-24: transfer to 50 km
August 20: turn at 80 km
Second triangular “orbit” averaging 50 km, August 24-Sep 3
August 24: begin first leg
August 27: begin second leg
August 31: begin third leg
September 3-10: transfer to global mapping orbit at 30 km
September 10-24: global mapping at 30 km
September 24-29: night excursion and transfer to 20-km orbit
(September 25: announcement of landing site selection?)
September 19-October 10: close observations at 20 km
October 10- : close observations at 10 km
November 11: Philae lands
This info is also available here in the blog, which includes an animation to describe the trajectory: https://blogs.esa.int/rosetta/2014/08/06/what-rosetta-does-now/
The belly of duck/ET
That ‘mare’ just at the middle
seems promising for landing.
Orbits shouldn’t get along at all
with 67P shape so its going to be more
of the comet hitting Philae than
some kind of landing.
This belly surface looks less weatherized
than that of the head of even
the back of duck/ET.
The ‘snow’ in the neck
sounds to me the more promissory,
but this area is closer to what Philae
was designed to land on.
🙂
The problem is you would be landing in a thick layer of dust, probably not optimal for research. Easy, safe…assuming you could stick your harpoons in it, but not very exciting science-wise.
Fully agree with you…
Are this harpoons
‘fisher’ kind?,
‘batman’ kind?
slooow motion kind?
The comet has a low density of app. 0,1. Does anyone know if this might be explained by a popcorn or styrofoam -like structure filled with voids?
Yes. Sizeable voids under the surface would explain a lot. Firstly, the low density of course. Then the “jets” where most of the out gassing occurs. Voids would be where gas pressure would build up, burst through a soft spot in the surface. If the voids were tiny, you would expect lots of tiny jets. Hartley and other nuclei had sizeable discrete jets. Of course, the pressure below the jet and the temperature would imply the liquefaction of water, which would explain some of the minerals found in stardust.
nice post health in your hands
Gotta love that hexagonal crater with a flat floor at the right edge of the smooth plain. In fact, several craters appear on the rim of the central smooth plain, and one of these craters (about 4 o’clock position) have a crater on its rim, all with flat, smooth floors and sharp ridges. Only pattern I’ve seen this occur in is electric discharge machining.
I’m sure Rosetta will make its revolutionary discoveries soon enough.
Some chimneys seem four sided.
Hi Ross,
many features look like the result of electric discharge machining, some photos show paired deep parallel sided holes, like a plunge cut. Also some of the rocks on the floor of some of the flat areas even look a bit like the shape of the comet and consistent with the shapes produced in labs when discharging into sand or rock.
regards
After all that sleep, Sleeping Beauty/Rosetta is alive a kicking. Full credit to the Rosetta teams and to all the other wondrous projects ESA has operating and planned either by itself or in partnership with other agencies.
Have you got a chemistry profile yet on the “head” and “body”?
Has any set sequence of the ‘Tumbling path’ been ascertained yet, or is it random?
I read that this is a recent Comet in our Solar system, I wonder why it now decides to enter our system and where was it before?
Clive
I have a question about the 2 discoverers of the Comet 67P/ C – G.
Have they any involvement in the present Rosetta probe workings?
They must be amazed at seeing close up of the comet they discovered.
It would be interesting to hear of any comments about it that they may have made.
Clive
I have since found out that the Comets path going near Jupiter changed its course as Jupiters mass is so large and its gravitational pull so great it could deviate the Comets track!
Also the Comet may not be visible to the naked eye and you would need a telescope to see it!
Clive
Hi Clive, Perhaps you found these links already, but in case you would like to read more, there is more about the history of 67P/C-G’s orbit here: https://sci.esa.int/rosetta/14615-comet-67p/
And more about observing the comet from Earth, here: https://blogs.esa.int/rosetta/2014/06/13/the-role-of-amateur-astronomers-in-rosettas-mission/
Yes, to me it looks like “tuff”: the material that form the “icing” on Yucatan, Mexico. So exiting to follow here, what goes on in the inside in this micro gravitation environment.
Thank you Emily, I was pleased to read through the 2 Links you gave.
I am enthralled by the happenings and to see something that no man has set eyes on before.
Clive
(Editted)
Re the density, I have looked at all the photos, especially where there are steep carved escarpments and also at the striated part of the head (that looks like its been exposed to erosion) and I can see no loose conglomerated of ice snow and boulders.
The comet looks like homogeneous hard rock, no ice and no Styrofoam type porosity.
It makes the low specific density hard to believe, Have you been able to re-access the mass and density of the comet from the pull of the comet?
Will you be able to do this before the lander is launched?