On October 1, 2014, NASA engineers managing the Solar Terrestrial Relations Observatory-B (STEREO-B) spacecraft did what every computer user does occasionally – they gave it a hard reset. Like most computer users, they found this doesn’t always work and they lost contact with Stereo-B for 22 months. On August 21, 2016, contact was reestablished with STEREO-B using NASA’s Deep Space Network. What happened and will the engineers who did the reset finally stop being picked on?
The nearly identical spacecrafts STEREO-B (for ‘before’) and STEREO-A (for ‘after’) were launched in October 2006 and placed in Earth orbit before and after the planet (duh) to give stereoscopic views of coronal mass ejections (CMEs) – those solar eruptions that can send up to 10 billion tons of the Sun's atmosphere into the solar system at a speed of one million mph (1.6 million kph) to damage or destroy satellites, mess with power grids, cause health issues with ISS astronauts and distort the Earth's magnetosphere. In other words, STEREO-A and B formed an effective early warning systems for dangerous magnetic storms.
So why did NASA mess with STEREO-B? According to its ‘published’ excuse, it was about to move behind the Sun and lose contact with mission operations so they ran a 72 hour reset test to make sure everything was functioning OK. Everything was … until the test was over. At that point, B went bye-bye and stopped functioning.
Fortunately, the last bits of data sent showed the failure was caused by the instrument that rotates the craft towards the Sun to recharge its batteries. Unfortunately, without it the batteries drained and the B was dead.
Or was it? NASA continued to attempt to connect with STEREO B on a weekly and then monthly basis using the Deep Space Network – the world-wide network of large antennas and communication facilities that supports interplanetary spacecraft missions. Nothing happened until August 21, 2016, when apparently STEREO B inadvertently tilted to an angle that allowed its batteries to get a tiny charge and wake it up.
Is it time to put Telstar on the ‘stereo’ and celebrate? Not quite. The instrument still doesn’t work so NASA is hoping the charge holds until a fix can get uploaded. Fortunately, STEREO-A continues to function in ‘mono’. Meanwhile, NASA engineers with “STEREO-B Mission Operations” on their badges continue to experience cramps from constant finger-crossing.