Mars Express Status Report April 2005
The first quarter of 2005 largely was marked by the start of the missions’ second eclipse season. Some of the longest eclipses left only very little margin in which science operations could be conducted, yet this was successfully achieved and, with the eclipse durations getting shorter, science data taking was gradually resumed at full speed.
A problem in maintaining the correct thermal environment for OMEGA caused one week of no science operations for this instrument in February. The problem has since been fixed.
A Solid State Mass Memory (SSMM) anomaly, this time only affecting HRSC data taking, occurred and was investigated. A new delivery of the SSMM software (fixing multiple known SSMM anomalies) was received and should be ready for upload to the spacecraft towards end-June.
As reported earlier, since early 2004 some 21 anomalies have been seen where the solar array on the -Y axis did not reach the commanded position as expected. Recently the control was switched to a redundant unit, and also there the problem manifested itself within a few days. Investigations continue, and in the meantime it has been decided to minimise solar array rotations by not updating its position during slews. The resulting power penalty can currently be accepted, but the effect during the October 2005 eclipse season will have to be investigated.
Following the upload of some outstanding patches on the redundant star tracker unit (applied and functional on the main star tracker since a few months), the star tracker showed anomalous behaviour. This is being investigated.
Preparations for the MARSIS deployment are ongoing and an overall schedule leading up to the deployment has been agreed. A final review is scheduled for 8 April, with a tentative start of the deployment window on 2 May.
Operations and archiving
Science operations are proceeding well. Illumination conditions are gradually degrading and start to favour the night side observations.
A number of activities (regarding data recovery and the implementation of new procedures for Radio Science and new pointing modes) have had to be suspended to free sufficient manpower for the preparation of the MARSIS deployment operations.
The first version of the Planetary Science Archive, containing the public Mars Express data, was released in February 2005. While not all data, which should have been contained in the archive, were actually delivered by the PI teams, the archive is actively being used, and we expect to be able to generate some statistics on its use soon.
Science highlights
After more than one year of operations around Mars, the First Mars Express Science Conference took place on 21-25 February at ESTEC. Registration reached 244 people (excluding media) from Europe, the United States, Japan, Russia and other countries. The programme included 120 oral presentations and 120 posters covering all scientific aspects of the mission, from an historical perspective to the latest intriguing findings. The topics addressed include results from the interior and subsurface of Mars; Mars geology, mineralogy and surface chemistry; the Polar Regions and their ice caps; the climate and atmosphere of Mars and the interactions between surface and atmosphere; the space environment around Mars, and the planet’s moons. A special session on exobiology and the search for life was also held. All in all the conference was a great success, and about 260 participants saw a full week of exciting new results and interesting debates.
A series of papers on OMEGA results, largely focusing on Mars surface diversity and seasonal measurements of the polar caps, was published in the journal Science. These papers were also discussed in an OMEGA dedicated session of the Lunar and Planetary Science Conference (LPSC; 14-18 March, 2005).
A number of HRSC results, on the ‘Frozen Sea’ story and recent glacial and volcanic activity on Mars were published in Nature. Also these results were discussed at the LPSC where, in general, it was clear that the Mars Express results have an important impact on the current thinking about Mars and its (recent) past.
