Mars Global Surveyor

The Mars Global Surveyor orbiter, which operated on Mars for more than nine years, was designed to study the composition of Mars, map its topography and monitor weather patterns. The orbiter made a number of discoveries about the Red Planet, including evidence of liquid water at or near the Martian surface.

Observations from the Mars Global Surveyor, especially its identifications of water-related minerals, were used to determine drive routes for the Mars Exploration Rover Opportunity in 2010.