Mars Express (European Space Agency)

Destination: Mars. Launched: June 2, 2003. Arrival: Dec. 26, 2003. Mission: To search for subsurface water from orbit and drop a lander on the Martian surface. Instruments on the orbiting spacecraft study the atmosphere and the planet's structure and geology. The lander, Beagle 2 (named after the ship on which Charles Darwin sailed), was scheduled to take photographs, gather soil samples, and examine rocks and soil microscopically—all in the search for signs of past life on Mars. Beagle 2 separated from the orbiter on Dec. 19, 2003, but contact was lost. The orbiter continues its mission, imaging the planet's entire surface, mapping the composition of the surface and atmosphere, determining the structure of the subsurface, and studying the atmosphere.