When Spacecraft Misbehave
Engineers get creative when the error message comes from 50 million miles away.
- By Zoe Krasney
- Air & Space magazine, November 2013
NASA / JPL-CalTech
The Curiosity Rover, NASA’s Mars Science Laboratory, has been grabbing attention since August 2012, when it landed in Gale Crater in a spectacular fashion. The rover began its trek toward Mount Sharp, about five miles away, and almost immediately began sending back discoveries from the Martian surface. Then one night last February, project mission manager Jim Erickson was awakened by a call. “Ground control said they were getting some interesting telemetry from the Mars rover relay,” Erickson says.
Team members at NASA’s Jet Propulsion Laboratory in California had noticed the problem when Curiosity failed to send back the data it had recorded for the day and go into regular sleep mode. That meant something was wrong with the rover’s main computer. The engineers woke up Erickson and switched the rover over to its secondary computer, which they call the B-side, a move that automatically puts the rover into safe mode so the team can root around for the problem.
Erickson was concerned, but he was a veteran at space hardware troubleshooting, having worked on the Mars rovers Spirit and Opportunity—and Galileo. Sure enough, his team located damaged memory hardware in the A-side primary computer. The team could reprogram the A-side to not recognize the damaged parts, but Curiosity was working just fine using the B-side, so they decided to keep it as the rover’s primary system. In the space business, it’s always good to fly with a spare.