Mars Curiosity rover reaches Mount Sharp, prepares for drilling mission

June 23, 2014: NASA's Curiosity Mars rover self-portrait.

June 23, 2014: NASA's Curiosity Mars rover self-portrait.  (AP/NASA, JPL-Caltech, MSSS)

NASA's Curiosity rover is about to conduct some serious scientific drilling at Mars.

The space agency announced Thursday that the rover has reached the base of Mount Sharp, its destination since landing two years ago. Officials say drilling could begin as early as next week at an outcrop of rocks called Pahrump Hills.

Mount Sharp, located in ancient Gale Crater, rises nearly 3½ miles.

A scientific review panel has criticized the Curiosity team for an extended mission that involves too much driving and too little sampling. On Thursday, project scientist John Grotzinger of the California Institute of Technology promised "we are going to do a lot more drilling" now that the six-wheel Curiosity is at Mount Sharp.

NASA says Curiosity remains healthy, aside from worn wheels.