NASA Rover Drills Into Martian Rock

LOS ANGELES (AP) – NASA’s Opportunity rover extended its arm and played robot geologist, drilling into a martian rock that has intrigued scientists back on Earth.

The six-wheeled rover used the rock-abrasion tool on its instrument-tipped arm to grind a fraction of an inch into the surface of a rock in a formation dubbed “El Capitan,” project manager Richard Cook said Tuesday.

The rock’s weathered surface was ground away so that the rover could examine the material underneath and photograph it in microscopic detail. Results were expected to take several days to reach Earth.

“It’s Christmas Eve and all the scientists are anxious and excited with anticipation,” deputy main scientist Ray Arvidson said Tuesday.

Opportunity also took a siesta, shutting down briefly to recharge its batteries. NASA scientists said the rover has been doing a lot of scientific work at night, expending the energy from its solar cells. Because Mars is beginning its winter season, the days are getting shorter and less sunlight is hitting the solar panels.

“El Capitan” has been the rover’s main concern for several days. The outcrop, about the height of a street curb, rings a portion of the crater in which the rover is rolling. Previous microscopic images show fine layering in the rock and mysterious BB-sized granules.

Scientists involved in the $820 million Mars mission are mulling several theories of how the glossy, sandblasted rock formed, including volcanic eruptions, windblown dust or sediments settling out of a body of water.

The new data could settle the issue. Scientists are also hoping the rover mission can uncover evidence of a watery, life-supporting past for the Red Planet.

Halfway around Mars, Opportunity’s twin rover, Spirit, continued to roll toward a crater, traveling nearly 100 feet on Tuesday. NASA planned to send the rover a short distance farther, then pause for a few days for observations, Cook said.

Spirit, which drilled a rock earlier this month, is about 300 feet from the crater nicknamed “Bonneville.” Scientists expect the rover to reach its rim and peer into it for the first time in mid-March, Arvidson said.

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