NASA's spectacular images of Mars

A Martian crater called "Santa Maria" is seen in this image released by NASA January 20, 2011. NASA's Mars Exploration Rover Opportunity is spending the seventh anniversary of its landing on Mars investigating a crater called "Santa Maria," which has a diameter about the length of a football field. This scene looks eastward across the crater and has been assembled from multiple frames taken by the panoramic camera (Pancam) on Opportunity during the 2,453rd and 2,454th Martian days of the rover's work on Mars on December 18 and 19, 2010. (REUTERS)