NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft has been out of service for most of the year, but thanks to a very clever hack, the probe is now using the stars to navigate its way around the planet red.
The probe had been in safe mode since February, but NASA engineers managed to fix the problem by uploading new software to the spacecraft. MAVEN resumed scientific and relay operations on May 28, after recovering from an extended safe mode, according at NASA. “The team really tackled an existential threat,” said Rich Burns, MAVEN project manager at NASA’s Goddard Space Flight Center, in a statement.
Launched in November 2013, MAVEN entered orbit around Mars in September 2014 with the aim of probing the planet for clues as to why it lost so much of its atmosphere during its early stages. Understanding the process by which Mars lost large amounts of its atmosphere is crucial to determining whether the Red Planet was once habitable, as it may have potentially hosted life billions of years ago.
The mission had gone well, with the probe doing a good job in Mars orbit and NASA extending the spacecraft’s mission duration five times. But on February 22, the team lost contact with the spacecraft.
Here’s what happened to the aging orbiter: MAVEN encountered a problem with its inertial measurement units (IMUs), which measure the spacecraft’s rotation to determine its attitude in space, or its ability to maintain or change its orientation relative to where it wants to go. . There are two IMUs on the spacecraft, a main unit and a backup unit. When communication with MAVEN was restored, the ground crew found that the spacecraft was disoriented and unable to determine its attitude from either of its two IMUs.
The spacecraft then entered ominous safe mode, which floated it through space while science operations were on hold. While MAVEN hibernated, the engineering team behind the mission worked to develop a system that would allow the spacecraft to navigate, not with its IMUs, but using stars as static reference points. The team was already working on developing this stellar navigation software, but it wasn’t supposed to be ready until October. Given the dire situation, however, the spacecraft needed help from the stars as soon as possible.
“By the time we ended up on the standby computer, the spacecraft had been trying to fix the issue with the IMU-1 for about 78 minutes,” said spacecraft team leader Micheal Haggard. Lockheed Martin MAVEN, in a press release. “We ended up on IMU-2, and the pressure was on to get all-stellar mode ready as soon as possible.”
The stellar navigation system – luckily five months ahead of schedule – was ready to go. On April 19, the team connected the software to the spacecraft, turned off the backup IMU, and turned on the MAVEN science instruments again. MAVEN, about two days after returning to action, even managed to spot a coronal mass ejection from the Sun that impacted Mars.
This was MAVEN’s second time in Safe Mode, the first time shortly after its scientific instruments were powered up in 2014, the result of a problem which forced it to close for almost a week. Looking ahead, the spacecraft has enough fuel to last until 2030, and its backup IMU is still there in case MAVEN needs it from time to time.