Hubble Space Telescope goes into sleep mode due to gyroscope malfunction

by Marc Van Norden

The Hubble Space Telescope, which revolves about 600 kilometers above the ground, is a facility that can be said to be a "space observatory" capable of astronomical observations with difficult accuracy from the ground. It is reported that "the Hubble Space Telescope has entered sleep mode" because the gyroscope used to control the attitude of such a Hubble Space Telescope has failed.

Hubble Space Telescope in 'Sleep Mode' After Gyroscope Failure - Motherboard
https://motherboard.vice.com/en_us/article/mbdxxb/hubble-space-telescope-in-sleep-mode-after-gyro-failure

By using the gyroscope, the Hubble Space Telescope keeps its posture while orbiting the orbits above the Earth. Each of the six installed gyroscopes is 6 inches long (about 15 cm) and weighs about 6 pounds (about 2.7 kg). Inside the gyroscope the gas powered wheels are rotating at 19,000 times per minute and the Hubble Space Telescope corrects the position along the axis of the gyroscope.

The gyroscope is essential for the Hubble Space Telescope, which continues to focus on a certain point of the vast universe area for a long time and photographs astronomical objects. Without a gyroscope, the Hubble Space Telescope can not control the attitude to continue focusing on the same place for a long time, and can not capture beautiful pictures by capturing a small amount of light with long exposure.

One of the gyroscopes of such a Hubble Space Telescope has failed on Saturday, October 6, 2018 (Saturday). Mr. Rachel Osten , deputy director of the Hubble Space Telescope, said, "It has been a very stressful weekend," until the dealing with the broken gyroscope was done the Hubble Space Telescope was in safe mode It is clarifying that there is.

It's true. Very stressful weekend. Right now HST is in safe mode while we figure out what to do. Another gyro failed. First step is try to bring back the last gyro, which had been off, and is being problematic.

- Dr. Rachel Osten (@ rachelosten) October 8, 2018

The Hubble Space Telescope did not always use all six gyroscopes, but four of the six gyroscopes were in operation when a fault occurred. According to the European Space Agency (ESA), it seems necessary for at least three of the six gyroscopes to operate in order for the Hubble Space Telescope to achieve optimal efficiency.

Osten et al. Hubble Space Telescope staff continues without resting the gyroscope recovery work, but even if the gyroscope can not be restored, that does not mean that the Hubble Space Telescope will not be usable. The Hubble Space Telescope is designed in advance to operate even with just one gyroscope and the lack of gyroscope limits the area of ​​the universe where the telescope can observe.

In fact, the Hubble Space Telescope launched in 1990 was controlled by only two gyroscopes from 2005 to 2009. During the same period, it was said that the two gyroscopes were kept as spares so that the Hubble Space Telescope would not stop completely. In 2009, the astronauts of the International Space Station carried out gyroscope replacement work, so we again controlled the Hubble Space Telescope with three gyroscopes and kept the remaining three as spares .

by NASA Goddard Space Flight Center

Osten tweeted about the breakdown of the gyroscope this time, "The breakdown of the gyroscope was predicted from the spring of 2018, and it continued to operate for more than 6 months longer than this prediction" , He says that the Hubble Space Telescope is not in a really dangerous state.

If the repair of the gyroscope failed, Mr. Osten is considering controlling the Hubble Space Telescope with one gyroscope. It seems that there is not so much difference between the state of 1 gyroscope and the state of 2, "Even in the state where only one gyroscope is being used, astronomers around the world can use the Hubble Space Telescope I will ask you. "