[UPDATED] Mars Express chats with Curiosity: Practice makes perfect

UPDATE 16 June: MEX Deputy Spacecraft Operations Manager James Godfrey just emailed to report that yesterday's MSL overflight seems to have gone rather well! "We have received good telemetry from the MEX Melacom radio and we are now in the process of analysing the data to extract the signal from MSL."


Today, Mars Express established a communication link with NASA's Curiosity rover (MSL) on the surface of Mars to conduct an important test prior to the arrival of ESA's ExoMars Trace Gas Orbiter (TGO), carrying the the ExoMars Entry, Descent and Landing Demonstrator Module (EDM), Schiaparelli, in October.

Curiosity selfie Credit: NASA/JPL-Caltech/MSSS

Curiosity selfie Credit: NASA/JPL-Caltech/MSSS

The test saw Curiosity serve as a stand-in (rove-in?) for Schiaparelli on the surface, transmitting a signal to MEX similar to how Schiaparelli will transmit during landing on 19 October. From orbit above, MEX had its lander communication system (Melacom) – with recently updated software – configured as it will be in October, and the orbiter tested receiving signals from below.

Here's the timeline of how today's test went, as programmed; all commands were uploaded in advance and the sequence was executed automatically on board (times in UTC).

  1. 2016-06-15 06:22:53.000 - MEX begins to slew to point the radio antenna towards MSL's position on the surface
  2. 2016-06-15 06:40:00.000 - Melacom Switches on
  3. 2016-06-15 06:55:00.000 - MSL starts transmitting its beacon
  4. 2016-06-15 06:55:00.000 - After a 15-minute warm-up, Melacom starts recording the signal from MSL
  5. 2016-06-15 07:05:00.000 - Melacom is powered down and the first part of the recording is complete
  6. 2016-06-15 07:10:00.000 - After a 15-minute wait, Melacom is powered back up
  7. 2016-06-15 07:14:00.000 - No waiting this time; 4 minutes allowed for start up as Melacom starts its second recording
  8. 2016-06-15 07:23:00.000 - MSL stops transmitting
  9. 2016-06-15 07:23:00.000 - Melacom is powered down and the second recording is complete
  10. 2016-06-15 07:23:10.000 - Test complete; MEX now begins to slew back to Earth; data will be dumped in a few hours
Melacom

A photo of the Melacom UHF communications package carried on Mars Express.

Note: Data were still arriving as we posted this, so no analysis to report yet:

Here's a brief description of the actual Schiaparelli arrival activity that this test was meant to exercise (see also: A little help from friends):

On 19 October, about 80 minutes before landing, expected at 14:48 GMT (16:48 CEST), Schiaparelli will wake up and a few minutes later begin transmitting a beacon signal (Schiaparelli will have se4parated from the ExoMars/TGO orbiter on 16 October).

Mars Express will already have pointed Melacom’s small antenna to the spot above the planet where Schiaparelli will appear, and will begin recording the beacon signal, ‘slewing’ – rotating – continuously so as to keep its antenna pointed to follow the module’s descent trajectory.

ExoMars 2016 Schiaparelli descent sequence Credit: ESA/ATG medialab

ExoMars 2016 Schiaparelli descent sequence Credit: ESA/ATG medialab

“Recording will continue through touch-down and the first approximately fifteen minutes of surface operation, after which Schiaparelli will be programmed to switch off and Mars Express will stop recording,” says Mars Express Spacecraft Operations Engineer Simon Wood.

The Schiaparelli signal data will be saved on board Mars Express in two segments; the first, larger, segment will record signals from wake up of the module until about 20 minutes before it reaches the Martian atmosphere, while the second, smaller, segment will record the descent through the atmosphere, touch down and the first 15 minutes of surface operations.

“Then, Mars Express will re-orient its main antenna toward Earth and download the second, smaller segment of recorded data, which should contain the first in-situ confirmation from Mars of Schiaparelli’s arrival and landing,” says Simon.

The data will be received via ESA’s Cebreros deep-space ground station, in Spain, by the Mars Express flight control team at ESOC, ESA’s mission control centre in Darmstadt, Germany, and then passed on to the ExoMars mission controllers.

Even more friends

Mars Express won’t be the only ‘set of ears’ listening in to Schiaparelli’s descent that day.

At Mars, NASA’s Mars Reconnaissance Orbiter (MRO) will monitor signals from Schiaparelli, but only after its landing, due to MRO’s orbital geometry.

MRO - Mars Reconnaissance Orbiter

Credit: NASA/JPL-Caltech

The TGO orbiter, while conducting its own critical orbit entry manoeuvre, will also record Schiaparelli’s descent and landing, but this data can only be downloaded some hours after it has completed orbit entry.

In the following days, Mars Express and MRO – as well as the other NASA Mars orbiters, Odyssey and MAVEN – will each serve as data-relay platforms, overflying Schiaparelli’s landing site in Meridiani Planum once or twice per day, picking up data transmitted from the lander during its nominal two- to four-day surface science mission, and relaying these to Earth.

Mars Express will also support the Schiaparelli mission through remote sensing measurements over the landing site during several weeks prior to the event.

 

Beagle retrospective

The UK-led Beagle-2 Mars lander, which hitched a ride on ESA’s Mars Express mission and was lost on Mars since 2003, has been found in images taken by NASA’s Mars Reconnaissance Orbiter. This close-up image has been sharpened to show possible details of the Beagle-2 lander on the surface of Mars.Credit: HiRISE/NASA/JPL/Parker/Leicester

The UK-led Beagle-2 Mars lander, which hitched a ride on ESA’s Mars Express mission and was lost on Mars since 2003, has been found in images taken by NASA’s Mars Reconnaissance Orbiter. This close-up image has been sharpened to show possible details of the Beagle-2 lander on the surface of Mars.Credit: HiRISE/NASA/JPL/Parker/Leicester

The big news today is the discovery, courtesy of NASA's Mars Reconnaissance Orbiter (MRO), of the UK-led Beagle 2 lander on the surface of Mars.

Beagle 2 was meant to parachute to the surface of Mars in December 2003, but after separation, the small craft was never heard from again.

In 2014, remains of Beagle 2 were spotted by the HiRise camera on board MRO; the images and full details are here.

We thought you might enjoy seeing some archive pics of Beagle, so we gathered a selection of images showing the craft on Earth, during launch and its last-ever view seen from Mars Express from space (by the VMC camera), just after separation on 19 Dec 2003.

And, today's YouTube video via University of Leicester

The UK-led Beagle 2 was due to land on Mars on 25 December 2003. The spacecraft was ejected from Mars Express on 19 December 2003. Nothing had been heard from Beagle 2 and the mission was presumed lost. Until now.

It has now been announced that the Mars Lander has been identified partially deployed on the surface of Mars by images taken by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter (MRO). These images show potential targets on the surface of Mars for the lander and key entry and descent components within the expected landing area.

Following analysis by members of the Beagle 2 team, which includes Leicester scientists, and NASA, the images show the Beagle 2 lander in what appears to be a partially deployed configuration with the main parachute and what is thought to be the rear cover close by.

Several interpretations of the image of the lander have been identified, consistent with the lander’s size and shape and changes in light reflections suggest that the object is metallic – again consistent with Beagle 2.

NASA to discuss science findings of Mars comet flyby

Our colleagues at NASA have announced a media briefing at 18:00 today to discuss initial findings from the 19 October comet Siding Spring flyby. Original post below, including links to webcast.

NASA will host a media teleconference at noon EST on Friday, Nov. 7, to provide initial science observations of comet C/2013 A1 Siding Spring’s close flyby of Mars and the impact on the Martian atmosphere.

NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft, Mars Reconnaissance Orbiter (MRO), and a radar instrument aboard the European Space Agency’s Mars Express spacecraft provided the first close-up studies of the comet that originated from the distant outer reaches of our solar system.

Briefing participants include:

- Jim Green, director, Planetary Science Division, NASA Headquarters, Washington

- Nick Schneider, instrument lead for MAVEN’s Imaging Ultraviolet Spectrograph, University of Colorado, Boulder

- Mehdi Benna, instrument scientist for MAVEN’s Neutral Gas and Ion Mass Spectrometer, NASA Goddard Space Flight Center, Greenbelt. Maryland

- Don Gurnett, lead investigator on the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument on Mars Express, University of Iowa, Iowa City

- Alan Delamere, co-investigator for MRO’s HiRISE instrument, Delamere Support Services, Boulder, Colorado

For dial-in information, media representatives should e-mail their name, affiliation and telephone number to Dwayne Brown at dwayne.c.brown@nasa.gov by 17:00 CET Friday.

Visuals will be posted at the start of the event at:

http://www.nasa.gov/mars/telecon

Audio of the teleconference will be streamed live at:

http://www.nasa.gov/newsaudio

The event will also be streamed, with visuals used by the participants at:

http://www.ustream.tv/nasajpl2

 

Waking up with a little help from our friends – Part 2

Not only is NASA helping Rosetta exit hibernation: ESA's very own Mars Express has been standing in for Rosetta in a series of crucial tests to ensure the NASA ground stations are ready to track the comet chaser. Andy Johnstone, from the Mars Express team here at ESOC, sent in this report.

Although all the attention for Rosetta wake up is mainly on the spacecraft itself, the other half of the equation is the ground stations that will be used to listen for the signal, NASA's DSS-14 in Canberra and DSS-63 in Goldstone.

If, by chance, no signal were to be detected on 20 January, this could mean that either (a) Rosetta has a problem, or that (b) possibly there is something wrong at the ground station.

Mars Express Credit: ESA/Alex Lutkus

Mars Express Credit: ESA/Alex Lutkus

Therefore, to reduce the possibility that there are any problems on ground, and since the radio systems on our two spacecraft are very similar, a test campaign was carried out using Mars Express; MEX 'pretended' to be Rosetta transmitting to the ground stations to ensure they are in perfect working condition.

The testing involved us, the MEX team, setting Mars Express to use its S-band transponders (which are normally only used for radio science or for emergency communications) to transmit at a very low bit rate, as Rosetta will on Monday.

This involved a lot of behind-the-scenes work from both ESA's Mars Express team and our colleagues at NASA DSN (including having them come in to work on weekends and on US Thanksgiving). But it paid off: a series of five test passes demonstrated to us that the 70m antennas and the teams manning them do a great job and are ready for Rosetta's wake up.

Best of luck to the Rosetta team and we're looking forward to the event on Monday!