Mars Express Status Report – February 2005
Mission Status
The last quarter of 2004 was largely a very productive period of science data taking, except for a 1-week period around early-December, during which an anomaly with the Solid State Mass Memory (SSMM) prevented nominal operations, and some antenna problems towards end-December. The SSMM anomaly, which occurred twice in a row, is most probably understood and can be fixed with a software patch.
Early 2005 saw a repeat, twice within a few days, of an anomaly in the Solar Array Drive Electronics (SADE), reporting a solar array movement not in-line with the commanded movement.
The planning of science observations for the 2005 eclipse season (starting in January) is very complicated with difficult trade-offs between power margins required and requests for science observations being made continuously. The first eclipses of this eclipse season show a thermal and power behaviour fully in line with expectations.
The JPL/ASTRO report on the MARSIS boom deployment behaviour has been received; followed by a report from industry (ASTRIUM) analysing the potential risks to the satellite and the mission. An independent team of experts is evaluating all of these reports and a first review meeting has been planned for 24 January 2005. A decision on the deployment, and its possible date, should follow soon thereafter.
Operations and archiving
Science operations are proceeding well. Illumination conditions are still favouring optical- and spectro-imaging observations.
Following an upgrade of the NASA DSS-14 (Goldstone – 70 m dish) station, it took longer than expected to declare the station ready again for normal operations. Mars Express had no other option than to choose to use the station while in “engineering demo” mode. This meant a fairly large number of unrecoverable data gaps occurred.
The next independent Mars Express Science Archive Review will be held on 26-27 January at ESTEC. This review will focus on the readiness for public release of the archive and actions taken to fix a number of items flagged at the July 2004 review.
Science highlights
Some 300 abstracts have been received in response to the call for papers for the dedicated Mars Express Science Conference, which will take place at ESTEC on 21-25 February 2005.
A paper was published in Nature on a study of the time-stratigraphic relationships of volcanic and glacial structures in unprecedented detail. This provides insight into the geological evolution of Mars. It is shown that calderas on five major volcanoes on Mars have undergone repeated activation and resurfacing during the last 20 per cent of Martian history, with phases of activity as young as two million years, suggesting that the volcanoes are potentially still active today. Glacial deposits at the base of the Olympus Mons escarpment show evidence for repeated phases of activity as recently as about four million years ago. Morphological evidence is found that snow and ice deposition on the Olympus construct at elevations of more than 7000 metres led to episodes of glacial activity at this height. Even today, water ice protected by an insulating layer of dust may be present at high altitudes on Olympus Mons.
