Mars Express Mission Extended

Co-ordinated from thebeginning with the Mars science and exploration activities of otheragencies, Mars Express has revealed an increasingly complex picture ofMars.

Since the start of science operations in early 2004, newaspects of Mars are emerging day by day, thanks to Mars Express data.These include its present-day climate system, and its geological‘activity’ and diversity. Mars Express has also started mapping waterin its various states.

In building up a global data set forcomposition and characteristics of the surface and atmosphere, MarsExpress has revealed that volcanic and glacial processes are much morerecent than expected.

It has confirmed the presence of glacialprocesses in the equatorial regions, and mapped water and carbondioxide ice, either mixed or distinct, in the polar regions. Throughmineralogical analysis, it found out that large bodies of water, suchas lakes or seas, might not have existed for a long period of time onthe Martian surface.

Mars Express has also detected methane inthe Martian atmosphere. This, together with the possible detection offormaldehyde, suggests either current volcanic activity on Mars, or,more excitingly, that there are current active ‘biological’ processes.

Thishypothesis may be reinforced by the fact that Mars Express saw that thedistribution of water vapour and methane, both ingredients for life,substantially overlap in some regions of the planet.

Furthermore,the mission detected aurorae for the first time on the Red Planet. Ithas made global mapping of the density and pressure of the atmospherebetween 10 and 100 kilometres altitude, and studied atmospheric escapeprocesses in the upper layers of the atmosphere. This is contributingto our understanding of the weather and climate evolution of the planet.

Thereis still much to be discovered by the extraordinary set of instrumentson board Mars Express. First, the 23-month extension will enable theMars Express radar, MARSIS, to restart Martian night-time measurementsin December this year.

MARSIS will continue its subsurfacestudies mainly in the search for liquid and frozen water. By combiningsubsurface, surface and atmospheric data, Mars Express will provide anunprecedented global picture of Mars and, in particular, its water.

Sofar, the High Resolution Stereo Camera has imaged only 19% of theMartian surface at high resolution. In the extended phase, it will beable to continue the 3D high-resolution colour imaging. After theViking missions, Mars Express is building today’s legacy of Marsimagery for present and future generations of scientists.

Thanksto the extension, Mars Express will also be able to study for a secondyear the way the atmosphere varies during different seasons, and toobserve again variable phenomena such as frost, fog or ice.

Finally,Mars Express will be able to revisit those areas where majordiscoveries, such as new volcanic structures, sedimentary layering,methane sources, nightglow and auroras, have been made, thus allowingto confirm and understand all aspects related to these discoveries.