Mars Polar Lander

Mars Polar Lander was an American robotic lander meant to study the volatiles and climate history of Mars at its south polar region. It was part of the Mars Surveyor program, managed by the Jet Propulsion Laboratory and built by Lockheed Martin Astronautics in Denver. Launched on 3 January 1999 on a Delta 7425 together with two Deep Space 2 microprobes, it was to land between about 73 and 78 degrees south latitude, dig a trench and analyse soil for water ice and carbon dioxide. Its payload included a robotic arm with camera, a stereo imager, a meteorology package, a gas analyser, a descent imager and a Russian laser ranger. No telemetry was received from just before its atmospheric entry on 3 December 1999. The investigation concluded that the deployment of the landing legs about 40 metres above the surface was read by the craft as touchdown, shutting down its engines, and the loss led to major changes in later planetary probes.