Mars rover Mars rover A Mars rover is a motor vehicle that propels itself across the surface of the planet Mars upon arrival. Rovers have several advantages over stationary landers: they examine more territory, and they can be directed to interesting features, they can place themselves in sunny positions to weather winter months, and they can advance the knowledge of how to perform very remote robotic vehicle control. There have been four successful robotically operated Mars rovers. The Jet Propulsion Laboratory managed the "Sojourner" rover, the "Opportunity" rover, "Spirit" rover, and, now the "Curiosity" rover. On January 24, 2016 NASA reported that
Opportunity mission timeline Opportunity mission timeline Opportunity, MER-B (Mars Exploration Rover – B), is a robotic rover active on the planet Mars since 2004. Launched on July 7, 2003, "Opportunity" landed on Mars' Meridiani Planum on January 25, 2004 at 05:05 Ground UTC (about 13:15 Mars local time), three weeks after its twin "Spirit" (MER-A), also part of NASA's Mars Exploration Rover Mission, touched down on the other side of the planet. While "Spirit" became immobile in 2009 and ceased communications in 2010, "Opportunity" remains active as of December 11, 2017, having already exceeded its planned 90 sol (Martian days) duration of activity