On Dec. 16, 2010, NASA's Mars Exploration Rover Opportunity make a new conquer! Little smart robot reached a crater about the size of a football field (about 90 meters (295 feet) in diameter). The rover team will use cameras and spectrometers during the next few weeks to examine rocks exposed at the crater. You can see image frames taken by Opportunity's navigation camera on Dec. 16
A football-field-size crater, named "Santa Maria"
Picture - Rover Opportunity, Image credit: NASA