Mars rover takes the plunge into crater

A Martian rover has taken the plunge into a crater on the Red Planet after a cautious toe-dip to ensure a slip-free way out.

"We want to maintain a safe egress route out of the crater for Opportunity, and by completing the backup drive over the sand ripple at the time, we have confirmed that we have one," said John Callas, Mars rover project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Opportunity is now exploring the interior of Victoria Crater."

Opportunity performed a quick in-and-out wheel slippage test on Thursday before taking a final plunge into the crater to begin several weeks of investigation on the big bowl's inner slope. It ended the day by driving about 20 feet (6 meters) inside the rim.

The robot explorer was set to enter into the crater in late June when a series of dust storms broke out and threatened to cut off sunlight to its solar cells. More than two months later, the dust from those storms has settled and both Opportunity and its twin, Spirit, have largely recovered.

The rover's first destination inside the crater is a light-toned layer of exposed rock that might preserve evidence of interaction between the Martian atmosphere and surface from millions of years ago.

Victoria exposes a taller stack of ancient rock layers than any crater Opportunity has previously visited during its 44 months on Mars. The mission was originally planned for three months.