Sojourner

On July 5, 1997, the six-wheeled robotic rover, Sojourner, rolled down a ramp from the Pathfinder spacecraft onto the Martian surface. The 23-pound, remote-controlled robot photographed and examined rocks selected by the scientific team on Earth. Sojourner was designed to roam for a week but ended up working 12 times longer than that.

Image credits: main image, courtesy NASA.

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