March 19, 2013
Curiosity Active Again After Entering ‘Safe Mode’ Over Weekend
Lee Rannals for redOrbit.com — Your Universe Online
Curiosity has been having a bit of trouble on Mars lately with its software, and yesterday NASA announced its prized rover entered "safe mode" again after more glitches had occurred.
The space agency said its engineers worked to diagnose the software issue that prompted the rover to put itself into the precautionary standby status over the weekend. Curiosity is now back to active status and is on track to resume its science investigations.
At the end of February, NASA first switched Curiosity to safe mode so they could investigate the main computer before returning the rover back to work. Curiosity has two redundant main computers in case one fails, an A-side and a B-side. The rover relied on its B-side for most of the trip to Mars, while it has used its A-side for the majority of its time on Mars since landing last August. However, a glitch occurred on the A-side, prompting NASA to put Curiosity in its safe mode until they were able to investigate and switch the rover to its B-side.
NASA said Curiosity initiated its automated fault-protection action on March 16 at about 8:00 p.m. PST. According to the space agency, the safe-mode entry was triggered when a command file failed a size-check by the rover's protective software.
"This is a very straightforward matter to deal with," said the project manager for Curiosity, Richard Cook of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We can just delete that file, which we don't need any more, and we know how to keep this from occurring in the future."
NASA said bringing its rover out of safe mode status on the B-side is expected to take a couple of days. Curiosity's A-side has been restored, so it is available as a backup.
Next, NASA said it would be checking the rover's active computer by commanding a preliminary free-space move of the arm.
"We expect to get back to sample-analysis science by the end of the week," said Curiosity Mission Manager Jennifer Trosper of NASA's Jet Propulsion Laboratory, Pasadena, Calif.
Engineers will hold off on sending Curiosity any commands for four weeks starting April 4 because Mars will be passing nearly directly behind the sun from Earth's prospective. This moratorium is a precaution against interference by the sun corrupting a command sent to the rover.
Curiosity has been on a roll with scientific discoveries since landing last year. Just recently, the rover was able to offer a better glimpse into Mars' past by revealing evidence for ancient environmental conditions favorable for life. Scientists using infrared-imaging capabilities on the rover said they found evidence of hydration minerals near a clay-bearing rock at a location Curiosity had visited earlier in Yellowknife Bay on the Red Planet.