After a journey of almost three years, NASA's Mars Exploration Rover Opportunity has reached the Red Planet's Endeavour crater to study rocks never seen before.

On Aug. 9, the golf cart-sized rover relayed its arrival at a location named Spirit Point on the crater's rim. Opportunity drove approximately 13 miles (21 kilometers) after climbing out of Victoria crater. Steven W. Squyres, Cornell professor of astronomy, continues as principal investigator for the science payload on NASA's Mars Exploration Rovers.

Endeavour crater, which is more than 25 times wider than Victoria crater, is 14 miles (22 km) in diameter. At Endeavour, scientists expect to see much older rocks and terrains than those examined by Opportunity during its first seven years on Mars. Endeavour became a tantalizing destination after NASA's Mars Reconnaissance Orbiter detected clay minerals that may have formed in an early warmer and wetter period. The name Spirit Point informally commemorates Opportunity's twin rover, which stopped communicating in March 2010. Spirit's mission officially concluded in May.

NASA's Mars Reconnaissance Orbiter, which launched Aug. 12, 2005, is searching for evidence that water persisted on the Martian surface for a long period of time. Other Mars missions have shown water flowed across the surface in the planet's history, but scientists have not determined if water remained long enough to provide a habitat for life.

NASA launched the Mars rovers Spirit and Opportunity in summer 2003. Both completed their three-month prime missions in April 2004 and continued years of extended operations. They made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life.