Sojourner Mars Rover

NASA Sojourner is a robotic Mars rover that landed in the Ares Vallis channel in the Chryse Planitia region of the Oxia Palus quadrangle on July 4, 1997. Sojourner was operational on Mars for 92 sols (95 Earth days but was designed for a mission lasting 7 sols, with a possible extension to 30 sols. It was the first wheeled vehicle to rove on a planet other than Earth and formed part of the Mars Pathfinder mission.

The mission carried a series of scientific instruments to analyze the Martian atmosphere, climate, and geology and the composition of its rocks and soil. In addition to scientific objectives, the Mars Pathfinder mission was also a “proof-of-concept” for various technologies, such as airbag-mediated touchdown and automated obstacle avoidance, both later exploited by the Mars Exploration Rover mission.