NASA tries savin' MAVEN as Mars probe loses contact with Earth

Spacecraft was 'rotating in an unexpected manner' and might have shifted orbit

NASA is still trying to recontact the MAVEN Mars orbiter after it stopped responding earlier this month, with fragmentary tracking data hinting the craft may be tumbling and off its predicted trajectory.

Earlier this week, the US space agency revealed that the MAVEN (Mars Atmosphere and Volatile EvolutioN) team had managed to recover a fragment of tracking data from December 6 that indicated the spacecraft was "rotating in an unexpected manner" when it emerged from behind Mars. The signal's frequency also suggested that the orbit's trajectory might have changed.

In the update, NASA wrote, "The team continues to analyze tracking data to understand the most likely scenarios leading to the loss of signal.

"Efforts to reestablish contact with MAVEN also continue."

The agency did not confirm whether the spacecraft had entered safe mode, in which an anomalous event causes the probe to shut down all non-essential systems and enter a safe state until communication with controllers can be restored. One space industry insider told The Register that "Safe mode will change the orbit as it involves firing the thrusters," and went on to explain that on their mission, recovery involves performing a maneuver "to undo the damage that safe mode entry has done to the orbit."

This is assuming that MAVEN's orbit has changed. NASA's language ("may have changed") is deliberately vague. There is, after all, precious little data for engineers to work with – just a fragment of Doppler data to hint that something is different. Our source noted that the team responsible for tracking the trajectory of their spacecraft typically needed an hour of decent signal, though the MAVEN team's needs might differ.

Engineers do not have the luxury of time for regaining control of the spacecraft. A solar conjunction (where Mars is obscured from the Earth by the Sun) is due shortly, during which the Deep Space Network (DSN) will be unable to communicate with spacecraft on or around Mars.

That mysterious trajectory change further complicates things. If the trajectory has changed, then engineers will have difficulty pinpointing where the spacecraft should be at any given time, hampering recovery efforts.

Having launched in 2013, MAVEN is a relative spring chicken when it comes to NASA's Mars fleet. The Mars Reconnaissance Orbiter (MRO) arrived in 2006, and the Mars Odyssey entered orbit in 2001. The latter, however, is running on fumes at the moment, having outlived its original mission by decades.

Other Mars orbiters include the European Space Agency's Mars Express, which was launched in 2003, and the ExoMars Trace Gas Orbiter.

Should MAVEN be lost, there is a chance that NASA might find itself down to two operational but aging spacecraft orbiting the red planet sooner rather than later. ®