NASA's Mars rover Curiosity has survived its four-day "brain transplant" in fine shape and is now gearing up for its first Red Planet drive, mission managers said Tuesday.
Engineers upgraded Curiosity's flight software over the weekend, switching the rover's main and backup computers from landing mode to surface mode. The four-day overhaul temporarily halted Curiosity's science observations and instrument checkouts, which had begun almost immediately after the rover touched down inside Mars' Gale Crater on the night of Aug. 5.
Those activities are resuming on the rover's ninth full Martian day — or Sol 9, in mission lingo — because Curiosity's brain surgery went well, researchers said. The switchover replaced the software that was required for the rover's landing with software that enhances Curiosity's capability to drive and use the instruments on its robotic arm.
"I personally like to think of it as an intellect upgrade, since the 'brain' remains the same," said Jim Donaldson, the mission's avionics chief engineer at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Curiosity mission systems manager Mike Watkins told reporters that ""we're now 'go' to continue our checkout activities." As part of the checkout process, Curiosity's handlers hope to turn the rover's wheels for the first time in the next week or so, Watkins added. [Gallery: Curiosity's 1st Photos of Mars]
"We're going to test the steering actuators on Sol 13, and then we are going to take it out for a test drive here probably around Sol 15," Watkins said. "We're going to do a short drive of, you know, a couple of meters, and then maybe turn and back up."
Seeking habitable environments
Curiosity is the centerpiece of NASA's $2.5 billion Mars Science Laboratory mission, which seeks to determine if the Red Planet could ever have hosted microbial life. To get at this question, Curiosity will analyze Martian rocks and soil with 10 different science instruments for the next two years or more.
The MSL team is interested in studying formations near the rover's landing site, which sits just downslope of an ancient alluvial fan — a feature likely created by water flowing downhill. But Curiosity's main target is the base of Mount Sharp, the mysterious 3.4-mile-high (5.5 kilometers) peak rising from Gale's center.
Mount Sharp's many layers preserve a record of Mars' changing environmental conditions going back perhaps a billion years or more, researchers have said. And Mars-orbiting spacecraft have detected evidence of clays and sulfates in the mountain's foothills, suggesting that Mount Sharp's lower reaches were exposed to liquid water long ago.
These foothills lie about 5 miles (8 kilometers) from Curiosity's landing site as the crow flies, researchers said. The rover will have to pick its way through a dune field to get there, and it will likely make a few stops en route to study interesting rocks.
Curiosity can cover about 330 feet (100 meters) per day — about the length of a football field — so it will take the rover a while to reach its destination.
"It's going to take a good part of a year to finally make it to these sediments on Mount Sharp," said MSL deputy project scientist Ashwin Vasavada of JPL.
Itching to move
It will be another month or so until Curiosity and its instruments are fully vetted and the rover is ready to devote itself completely to science operations, Watkins said. But everything looks good so far.
"We have a fully healthy rover and payload," Vasavada said.
He and the rest of the MSL team are eager for Curiosity to really get rolling on the Martian surface.
"I think it's fair to say that the science team and our rover drivers and really everybody are kind of itching to move at this point," Vasavada said. "So the science and operations teams are working together to evaluate a few different routes that will take us eventually to Mount Sharp."
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