Another Mars Orbiter Goes Into Safe Mode

NASA's oldest Mars orbiter Odyssey has entered a safe mode that has stalled its science observations. But mission controllers think they have identified the cause and plan to revive the spacecraft soon..

Engineers diagnosed the cause of the Saturday event as the 8-year-old spacecraft's proper response to a memory error. The likely cause is an upset in the orbiter's memory error external bus, the same thing that caused a similar glitch in June 2008. Odyssey has been orbiting Mars since 2001.

"This event is a type we have seen before, so we have a known and tested path to resuming normal operations," said Odyssey project manager Philip Varghese at NASA's Jet Propulsion Laboratory in Pasadena, Calif., in an update.

Odyssey's fellow Mars-orbiting spacecraft, the Mars Reconnaissance Orbiter, is also currently in a safe mode, though it has been stuck like that since August.

While Odyssey was in safe mode over the weekend, it remained in communication with ground controllers and maintained healthy temperatures and power.

To clear the memory error, the team commanded Odyssey to perform a cold reboot of the orbiter's onboard computer on Monday. The spacecraft reported that the reboot had been completed successfully, mission managers said.

In addition to Odyssey's own major scientific discoveries and continuing studies of the planet, the spacecraft has played important roles in supporting the missions of the Mars rovers Spirit and Opportunity and the Phoenix Mars Lander.

Until Odyssey is available again as a communications relay, Spirit and Opportunity will be operating with direct communications to and from Earth.

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