NASA tries Mars rover's Mastcam to work out where MAVEN is

"The agency last heard from the MAVEN (Mars Atmosphere and Volatile EvolutioN) orbiter on December 6, and the last fragment of tracking data recovered by engineers indicated that the probe was tumbling and that its orbit trajectory might have changed. The latter point is highly significant - if any engineers can't work out where the spacecraft is, contacting it is highly challenging, either from Earth or using one of the other Mars orbiters or rovers."

"According to NASA, on December 16 and 20, the Curiosity trundlebot team used the rover's Mastcam instrument in an attempt to image MAVEN's reference orbit, but the spacecraft was not detected. The problem now is that the solar conjunction is approaching. The Mars solar conjunction occurs when Mars and Earth are on opposite sides of the Sun. This means that from Monday, December 29, until Friday, January 16, NASA will not have contact with any Mars missions and won't be able to fire commands at MAVEN in the hope of getting a response from the stricken spacecraft."

"A spacecraft upset usually triggers safe mode, in which the probe detects an issue, shuts down all non-essential systems, and awaits instructions. NASA, however, has not confirmed that the probe has entered this mode. A space industry insider told The Register "If it were [in safe mode] they [NASA] would be more successful in communicating with it. "So whatever has happened, it hasn't been able to reach safe mode.""

MAVEN has not transmitted since December 6 and recovered tracking fragments indicate tumbling and a possibly altered orbit. Attempts to image the orbiter with Curiosity's Mastcam on December 16 and 20 failed to detect the spacecraft. The approaching Mars solar conjunction (December 29–January 16) will suspend communications with all Mars missions, preventing command uploads or contact attempts until January 16, 2026. Safe mode entry has not been confirmed, and an industry insider suggested the spacecraft has not reached that state. Unexpected rotation implies an energetic event, and a changed orbit would complicate recontact and recovery efforts. Teams will resume contact attempts once the conjunction window closes.

Read at Theregister