Mars Rover Opportunity Climbs Red Planet Ridge (Photo)

NASA's Opportunity Mars rover is tackling some of the toughest terrain the robot has encountered in its twelve years on the Red Planet. Opportunity began climbing up a 30-degree slope known as Knudsen Ridge late last month, in an effort to reach and study Mars rocks that may have been exposed to liquid water billions of years ago. The six-wheeled robot has managed very well on the slope — the steepest Opportunity has dealt with since March 2004, just two months after it touched down on the