NASA’s Mars Reconnaissance Orbiter (MRO), at Mars since 2006, put itself into a precautionary standby mode on Feb. 15 in response to sensing an unexpectedly low battery voltage.
The orbiter is solar-powered but relies on a pair of nickel-hydrogen batteries during periods when it is in the shadow of Mars for a portion of each orbit. The two are used together, maintaining almost identical charge during normal operations.
The spacecraft remains in communication with Earth and has been maintaining safe, stable temperatures and power, but has suspended its science observations and its service as a communications relay for Mars rovers. Normal voltage has been restored, and the spacecraft is being monitored continuously until the troubleshooting is complete.
“We’re in the diagnostic stage, to better understand the behavior of the batteries and ways to give ourselves more options for managing them in the future,” said MRO Project Manager Dan Johnston of NASA’s Jet Propulsion Laboratory, Pasadena, California. “We will restore MRO’s service as a relay for other missions as soon as we can do so with confidence in spacecraft safety — likely in about one week. After that, we will resume science observations.” [More at link]