The missions main objective is to search for sub-surface water from orbit and drop a lander on the Martian surface. Seven scientific instruments onboard the orbiting spacecraft will perform a series of remote sensing experiments designed to shed new light on the Martian atmosphere, the planets structure and geology. The lander, called Beagle 2 after the ship in which Charles Darwin set sail to explore uncharted areas of the Earth in 1831, is an exciting opportunity for Europe to contribute to the search for life on Mars. After coming to rest on the surface, Beagle 2 will perform exobiology and geochemistry research. As well as its science objectives, Mars Express will also provide relay communication services between the Earth and landers deployed on the surface by other nations, thus forming a centre piece of the international effort in Mars exploration.
http://sci.esa.int/marsexpress/
