The Mars rover Opportunity will head into Victoria Crater in early July, but project managers say it may not make it back out.

There are no guarantees, but "the risk is worth the reward," NASA administrator Allan Stern told a media briefing.

This view of Victoria Crater on Mars was taken by the rover Opportunity as it was looking southeast from Duck Bay toward the dramatic promontory called Cabo Frio.
(NASA/JPL/Cornell )

They believe the rover can go into the crater, gather data and climb back, the project team announcing the mission said Thursday.

The rover's priority is to explore what scientists call "the bright band" visible inside the crater. It's believed to be a one-metre thick band of undisturbed bedrock from before the crater formed, perhaps billions of years ago.

The trip into the crater, which is 800 metres wide and 60 to 70 metres deep, is to begin with a test run as early as July 7.

"We call it a toe dip, but it's really both feet and both hands," said John Callas, the rover project manager. The plan is to advance all six wheels into the crater and, if all goes well, bring it immediately back out.

After any adjustments indicated from this test, they will continue into the crater from the Duck Bay entry point.

The image shows the rim of the Victoria Crater. It's 800 metres across and 60 to 70 metres deep.
(NASA/JPL/University of Arizona)

Duck Bay was selected after months of exploring the edge of the crater. It has a shallow slope, at least 100 metres of clear path into the crater, and an east-west orientation that is good for the solar-powered vehicle.

The Opportunity rover has already far surpassed expectations. What was expected to be a 90-day lifespan on Mars has now lasted 12 times as long.

Nonetheless, the scientists said there is still more science to be done and they don't want to lose Opportunity. Its sibling, Spirit, is also on Mars.

They fear the rover may become imbedded, a wheel may be disabled or the steering apparatus may fail.