Both Mars Rovers on Course for Research

The computer problems that plagued NASA’s Spirit rover have been repaired, and its twin, Opportunity, has rolled away from its landing site to begin studying an intriguing rock outcropping that may provide crucial information about the history of water on Mars, mission controllers said Friday.

“Our patient [Spirit] is healed,” said mission manager Jennifer Trosper. Engineers at Pasadena’s Jet Propulsion Laboratory erased Spirit’s flash memory and reformatted it.

The craft’s computer system is “like it was at the beginning, back at launch,” said software engineer Glenn Reeves.

The craft provided geologists with some unexpected results when it used the brush on its tool arm to sweep the surface of a rock called Adirondack.

“To our surprise, there was quite a bit of dust on the surface,” said geologist Ken Herkenhoff of the U.S. Geological Survey. “We selected the rock because it looked relatively dust-free.” The finding, he said, suggests that remote sensing of rocks may not give a true picture of their internal composition.

The team planned to use the arm’s abrasion tool overnight Friday to study Adirondack’s interior.

Opportunity, meanwhile, completed its 17-foot drive to the right end of the outcropping it will study, making stops and a couple of arcs in its path so engineers could determine how well the craft maneuvered in the Martian soil. The rover stopped about a foot farther from the rock formation, called Snout, than engineers had expected, mission manager Matt Wallace said.

That occurred because the rover was going up the side of the Meridiani Planum crater at an angle of about 13 degrees, he said, and there was 10% to 20% slippage as a result.

Now that Opportunity is at the outcropping, it will drive along a route parallel to it and take pictures so scientists can learn more about the layering visible in the rock.