After a short break, NASA announced that the Hubble Space Telescope has been made operational again. Problems with one of the gyroscopes caused Hubble to enter safe mode on November 19. Now that problem has been resolved and the world’s most productive space telescope is back in operation.

The telescope automatically went into safe mode on the 19th after one of its gyroscopes malfunctioned, but engineers restored it the next day. The problem with the gyroscope resurfaced, and on the 21st the telescope again suspended scientific work. It was restored again and went back to safe mode on November 23rd. Scientific studies were suspended until December 8. Now engineers have solved the problem and the space telescope has resumed scientific work.

Gyroscopes are part of the telescope’s pointing and aiming system, along with precision aiming sensors and jet wheels. Hubble’s gyroscopes have caused problems in the past. Scientific studies were stopped in 2018 due to problems with gyroscopes. “…these gyroscopes have a mind of their own,” STScI director Ken Sembach said at the time.

When Hubble was launched in 1990, it had six gyroscopes. They were unsuccessful, and in 2009 they were replaced by six new ones of different design. Now three of them have failed, leaving Hubble in the final three. There are no more Hubble maintenance missions, so when the last three eventually fail, Hubble will be just a relic. A majestic ruin, but a ruin nonetheless.

But there is still life on Hubble. NASA expects gyroscopes to last into the 2030s. In the meantime, expect occasional crashes, safe modes, and suspensions of scientific operations. Although the telescope was disrupted when one of the gyroscopes shook, there was still plenty of life left. If necessary, Hubble can also work with a single gyroscope. This will affect his work, but it will not stop it.

Although the telescope is working again, it is not fully operational. On Friday, December 8, the Wide Field Camera 3 and the Advanced Survey Camera resumed scientific observations.

The suspension of scientific work affected the telescope’s schedule. Observations were planned to support studies of Kuiper belt objects, the metallicity of moons of the Andromeda galaxy, type 1A supernovae, and other topics. We hope that some of this work will be restarted once the problem is resolved.