Mars Express Status: End of Solar Conjunction Period
Overall Mission and Payload Status
Most scientific payload operations were suspended between 22 August and
27 September, due to a period of solar conjunction. During this time,
however, radio science (MaRS) experiments of the solar corona were
carried out. On the egress from conjunction all spacecraft systems were
nominal.
After resuming payload operations, the pericentre position in the orbit
currently is off by about 1 minute with respect to the frozen orbit
prediction. Therefore, it may take up to 2 weeks to get back to the
frozen orbit by using nominal wheel off-loadings (no correction
manoeuvre is required).
Science Planning Status
Planning for the Medium-Term Plan of October 2004 is now finished. Due
to the favourable illumination conditions and latitudes with highly
valuable targets, a major share of the scientific data is being given to
the imaging instruments. During this period, coverage by the DSN 70m
antenna is essential due to the intense scientific activities to be
carried out. Pointing requirements for the November period have been
delivered, and also include high priority for the various imaging
instruments. Preparations for the planning of the second eclipse season
(from early January 2005 onward) have started.
Science planning is being carried out without taking MARSIS into
account, until another directive is given. Studies on the safe
deployment of the radar antenna for the MARSIS experiment are
continuing, and expected to be finished and lead to clear conclusions in
the last quarter of 2004.
It was decided not to use the opportunity to change the current orbit of
Mars Express around day 290. The SWT will establish the programmatic and
scientific need to perform such a manoeuvre during the next opportunity
for changing the inclination (at day 570), which will still be very
effective in modifying the characteristics of the extended mission
(eclipse duration and day-night balance).
Science Highlights
Two press releases were recently issued by ESA on two of the Mars
Express instrument results
PFS
New insights into the water and methane distribution in the
atmosphere.
Full story at ESA Science Media Centre
ASPERA
The solar wind is found to penetrate the Martian atmosphere down
to an altitude of 270 kilometres.
Abstract of article released in Science magazine
Full story at ESA Science Mars Express pages
In addition, the following images taken by the HRSC instrument were
released since the last status report:
10 September 2004
HRSC – Solis Planum
The displayed region is located south of Solis Planum at longitude 271°
East and latitude of about 33° South. It shows part of a heavily eroded
crater.
27 September 2004
HRSC – Ophir Chasma
The Ophir Chasma, a northern part of the Valles Marineris canyon, as
imaged at about longitude 288° East and latitude 4° South, shows
altitudes up to 5 km.
05 October 2004
HRSC – Grabens of Claritas Fossae
The displayed region is the eastern part of Claritas Fossae and the
western part of Solis Planum at longitude 260° East and latitude of
about 28° South, showing the characteristic ‘grabens’ running mainly
north-west to south-east.
