On Friday, the Hubble Space Observatory, which gave us phenomenal images of the celestial bodies in your milky way and beyond, has been put on a ‘safe mode’ after one of the three gyroscopes mounted on the spacecraft reached its end of life. Hubble Space Observatory was sent to scan through the cosmos on shuttle Discovery in April 1990 after which, it received a total of five repairs and servicing missions with the latest being in 2009.
Hubble Space Observatory has total six gyroscopes in order to keep it pointed straight at the target of which, three are of an older model and three are a newer model that was serviced during the last 2009 servicing mission. The gyroscope enables the spacecraft to glance at the target and collect data while being locked on it and it needs at least three gyroscopes to perform normally.
Out of the six gyroscopes mounted on it, two of the older design gyroscope have a history of failing after just 50,000 hours after being sent in the space which left the observatory with total four gyroscopes of which, Hubble used two newer and one older design of gyroscope keeping one newer version as a reserve for future.
Hubble team has been keeping an eye on every aspect of the observatory including the one older gyroscope unit which started acting weirdly indicating signs that it has reached its end of life and finally, it snapped on last Friday night leaving the Hubble with two newer units enabled and one newer unit disabled. This is why engineers at NASA turned on the third newer gyro but it soon began developing problems after it was turned on.
According to NASA, the third gyro had trouble reading the rates and data and considered that the spacecraft is in motion when it isn’t and thereby, engineers tried sending a software patch to fix the issue, however, the problem remained unaffected and that is why the Hubble team turned off the third gyro and has put Hubble in a safe mode until further investigation is done to find a way out.
In fact, Hubble Space Observatory can operate on two or even a single gyro although with reduced usage in case if it needs to cite NASA’s control laws. Although the Hubble team is optimistic about solving the issue in case if NASA isn’t able to find a way out, it will execute the single-gyro control for Hubble in order to preserve the life of the single remaining unit for future operations.
If the control laws are followed, Hubble might not be able to focus of fast moving objects as well as those objects which are close to it since a single gyro wouldn’t be capable to keep the giant spacecraft focus straight onto the target since it will have to use magnetometers and star trackers among other instruments to determine its aiming and orientation thereby taking a chunk of what Hubble could see.
According to Ken Sembach who is the director of Space Telescope Science Institute at the Johns Hopkins University, the team will attempt to bring the spacecraft back online in early 2020 if not earlier.