NASA rover knocked out as gigantic dust storm envelops Mars

CAPE CANAVERAL, Fla. (AP) — NASA's seemingly unstoppable Mars rover Opportunity has been knocked out by a gigantic dust storm that is enveloping the red planet and blotting out the sun.

Officials said today they're hopeful the rover will survive the storm, which already covers one-quarter of Mars and is expected to encircle the planet in another few days. It could be weeks or even months, though, until the sky clears enough for sunlight to reach the Martian surface and recharge Opportunity's batteries through its solar panels.

For now, Mars' oldest working rover is stuck in the middle of the raging storm, in round-the-clock darkness.

"By no means are we out of the woods here," said John Callas, the Opportunity project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "This storm is threatening, and we don't know how long it will last, and we don't know what the environment will be like once it clears."

Flight controllers tried late Tuesday night to contact Opportunity, but the rover did not respond. The storm has been growing since the end of May with unprecedented speed.

NASA launched the twin rovers Opportunity and Spirit in 2003 to study Martian rocks and soil. They landed in 2004. Spirit hasn't worked for several years. Opportunity, however, has kept exploring well past its expected mission lifetime.

Scientists aren't nearly as concerned about the newer, nuclear-powered Curiosity rover on the other side of Mars, which is already seeing darkening skies.

Dust storms crop up every so often at Mars, sending dust tens of miles into the atmosphere and turning day into night. Spacecraft orbiting Mars are too high to be affected.

There's no chance of Opportunity being buried or getting a wheel stuck in dust. Even in the worst of storms, only a layer of fine dust is left behind. Managers said the main concern is that dust could temporarily cover its optical instruments.