NASA Finally Establishes Communication with Lost Sun Probe

STEREO sun probe

After losing all contact with sun probe STEREO-B in 2014, NASA has managed to reestablish contact with the probe. NASA’s Deep Space Network tracked a signal from the space device earlier this week. Deep Space Network, an agency which tracks NASA’s various space missions, had been looking for a signal for months.

STEREO-B is one of two twin sun probes. Their names are short for Solar and Terrestrial Relation Observatory. According to the NASA website, their mission was to “Provide first-ever stereoscopic measurements to study the sun and space weather”. The mission began in 2006, and was supposed to last until 2008.

However, they decided to extended the length of the mission, and this is when problems started cropping up. In 2014, NASA tested a command loss timer. It worked as a hard reset for the probe in case it did not receive any information from Earth in 72 hours.

The test performed on STEREO-A worked perfectly, however STEREO-B, after sending a weak signal back to Earth, vanished off the radar.

In the extended mission plan, both sun probes would orbit behind the sun, for three months each. During the tests, STEREO-B entered this orbit, and scientists were no longer able to communicate with it.

In December 2015, the team behind the mission realized that STEREO-B had received incorrect information regarding its positioning. That meant it had no way to readjust its course.

Sun Probe Gets Lost

From the few bits of data they managed to get, it seems the sun probe incorrectly believed it was spinning. Its internal guidance systems probably tried to correct the spin. Since it wasn’t actually spinning, the correction made it wobble.

Both spacecraft have solar panels, and rely on solar energy for power. Because of the spinning motion, STEREO-B would probably not be able to keep its panels directed towards the Sun for long enough. In this case, it probably blacked out several times, since it didn’t have the necessary resources.

It would have been simple to change the sun probe’s trajectory if they could reestablish contact. But unfortunately, with communications down, and without any idea of where the probe might be, scientists had no way of adjusting its course

Thus STEREO-B drifted off into space, completely silent, until early this Sunday. However, it is not out of the proverbial woods yet.

Since they could not get in touch with the sun probe until now, the experts in charge of the mission don’t really know the condition it’s in.

They’re hoping to get the computers back online this week. After that, they will receive data from the craft once every 5 minutes. Right now, experts are worried because they don’t know the direction the propellant is facing. This is the part of the spacecraft that helps maneuver it, and change its course. If it is not facing in the right direction, STEREO-B could potentially drift off into space once again.

Because the probe is so close to the Sun, it will take a while before NASA can bring it down safely. Right now, it seems it is slowly moving towards Earth. By 2019, NASA hopes it’s going to be able to see it with the Hubble Telescope, and determine its status.

Image Source: Wikimedia