Opportunity At Endeavour Crater

NASA's amazing rover, Opportunity, has reached Endeavour Crater after a three-year drive over rugged Martian terrain. That drive began after Opportunity had already survived on Mars for four years.

Endeavour is the largest crater Opportunity has encountered so far, but the rover will likely not drive down to the crater floor. Rather, the current plan is to study rocks on the crater's rim. They seem to be different than rocks so far examined. Clays also seem to be present on the rim, and scientists are eager to study those. Clay is an indicator that liquid water existed in the area at some point, so studying the clay of Endeavour could produce another data point in the building case that Mars was once wetter and warmer than it is today. That, in turn, would strengthen the case that life could have existed on Mars.