The Hubble Space Telescope when it was deployed in April, 1990 from the Discovery space shuttle. Now, Hubble is in safe mode due to malfunctions. Credit: NASA/Smithsonian Institution/Lockheed Corporation

Hubble in Trouble—Space Telescope’s Future Uncertain After Main Computer Glitch

Will the Hubble Telescope continue its scientific work?

NASA specialists were unable to connect the backup memory module of the Hubble space telescope, which is why the observatory cannot yet resume scientific observations. In the near future, engineers hope to establish the true cause of the failure of the payload on-board computer, due to which the telescope went into safe mode.

The Hubble was launched into space in April 1990 and in its 31 years of operation in low-Earth orbit has transmitted tens of terabytes of scientific data to Earth, becoming one of the most famous orbital observatories. The telescope observes a variety of objects, from the Moon and comets of the solar system to record-breaking distant galaxies. Thanks to it, thousands of scientific articles have been written, revealing the mysteries of space to the public.

Hubble's mirror during production. Credit: NASA / ESA
Hubble’s mirror during production. Credit: NASA / ESA

On the evening of June 13, 2021, the onboard payload computer NSSC-1, responsible for managing and coordinating the operation of scientific instruments onboard the observatory and part of the module for controlling and processing scientific data obtained by the telescope, stopped working at the telescope.

As a result, the main computer, which no longer received the keepalive signal, automatically put all scientific instruments into safe mode. On June 14, engineers restarted the payload computer, but then the problem reoccurred.

Hubble's surveillance camera. Credit: NASA / ESA
Hubble’s surveillance camera. Credit: NASA / ESA

The telescope team decided on June 16 to switch to one of several redundant modules, after which the payload computer will work for 24 hours in test mode.

However, when the engineers tried to do this on June 16, the telescope initially did not execute the command to start the backup module, and on June 17 again it was unable to launch either the disabled or the backup modules.

This is far from the first observatory malfunction, the last maintenance of which was over a decade ago. In particular, over the past few years, there have been two problems with the WFP3 camera, and one of the telescope’s gyroscopes has failed. Nevertheless, in all cases, it was possible to restore its work.

Repairing the Hubble Space Telescope, 1997. Credit: NASA / ESA

Currently, the telescope team is analyzing all available data to determine the cause of the computer failure, and scientific observations will be resumed only after the problem is resolved.

At the same time, the telescope itself is equipped with two NSSC-1 computers, which can use any of four independent memory modules, so in a critical case, specialists will switch to another computer.

It is expected that the telescope will be able to work for several more years, but the official decision on this will be made in the summer of 2021. The last contract extension for Hubble’s science operations was announced in June 2016 and is due to expire on June 30, 2021.

Even then, it was expected that Hubble will continue to operate in the 2020s but with the current malfunctions, its future is not entirely certain. We will likely hear whether the project will be extended once again or not in the upcoming month.

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Jenner, L. (2021, June 16). Operations Underway to Restore Payload Computer on NASA’s Hubble. NASA. (2021, June 19). NASA reports trouble with Hubble Space Telescope.
Whitwam, R. (2021, June 18). Hubble In Safe Mode Again After Computer Failure [UPDATE]. ExtremeTech.

Written by Vladislav Tchakarov

Hello, my name is Vladislav and I am glad to have you here on Curiosmos. As a history student, I have a strong passion for history and science, and the opportunity to research and write in this field on a daily basis is a dream come true.

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