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Sojourner

The first rover to operate on another planet. Part of the Mars Pathfinder mission, Sojourner was a small, six-wheeled robotic vehicle that explored the Martian surface in 1997, analyzing rocks and soil using its onboard instruments.

Source: mars.nasa.gov

APODs including "Sojourner"

Pathfinder on Mars

04/07/2026

Pathfinder on Mars
Image Credit: NASA Astronomy Picture of the Day

On July 4th, 1997, using its own array of fireworks, a parachute, and a cocoon of airbags, the Mars Pathfinder spacecraft bounced like a giant beach ball at least 15 times before it came to rest on the surface of Mars at 10:07 AM Pacific Daylight Time. After its then novel airbag-assisted landing sequence was completed, Pathfinder transmitted this color mosaic to mission operators on Earth. In the scene from another world, the Mars Sojourner robot rover is visible in the foreground, crouched on top of the unfolded Pathfinder. About the size of a large house cat, the six-wheeled, solar-powered Sojourner became the first successful Martian rover. Surrounding Pathfinder are deflated airbags and the rock-strewn terrain of the Ares Vallis floodplain. In the distance Martian hills appear against a dusty brownish sky. The Pathfinder lander was subsequently renamed the Carl Sagan Memorial Station.