Three Generations of Mars Rovers with Engineers at JPL
Front and center is the flight spare for the first Mars rover,  Sojourner, which landed on Mars in 1997 as part of the Mars Pathfinder  Project. On the left is a Mars Exploration Rover Project test rover that  is a working sibling to Spirit and Opportunity, which landed on Mars in  2004. On the right is a Mars Science Laboratory test rover the size of  that project’s Mars rover, Curiosity, which is on course for landing on  Mars in August 2012. (via NASA)

Three Generations of Mars Rovers with Engineers at JPL

Front and center is the flight spare for the first Mars rover, Sojourner, which landed on Mars in 1997 as part of the Mars Pathfinder Project. On the left is a Mars Exploration Rover Project test rover that is a working sibling to Spirit and Opportunity, which landed on Mars in 2004. On the right is a Mars Science Laboratory test rover the size of that project’s Mars rover, Curiosity, which is on course for landing on Mars in August 2012. (via NASA)

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