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What is the cause of the Hubble telescope’s latest shutdown?2 min read

August 5, 2021 2 min read


What is the cause of the Hubble telescope’s latest shutdown?2 min read

Reading Time: 2 minutes

Recently, there was a glitch in the Hubble telescope’s journey in space. The payload computer, which manages the instruments that are onboard the telescope suddenly shut down, causing the telescope to stop working. It took NASA almost a month to rectify this and find out that the error was in the Power Control Unit (PCU)!

Does that not make any sense? Well, let’s pare it down!

Owliver’s Obscure Observation: The Hubble Space Telescope has been in operation since 1990, which means that most of the technology it uses was built in the 1980s, including the payload computer which manages the data that is received by the telescope. This is why it took scientists a long time to figure out what went wrong.

What is a PCU?

The PCU ensures and maintains a steady flow of electricity to the payload computer. A power regulator and a Secondary Protection Circuit (SPC) are key in this process. When the voltage exceeds or is under NASA standards, the SPC orders the payload computer to shut down! This is probably what happened in this situation as well.

Well, what did NASA say?

NASA deduced that the SPC triggered the shutdown. Either the SPC followed protocol and shut down, or it has degraded over time (since it’s a couple of decades old). This could have also caused the payload computer to shut down.

So, is it still being fixed?

NASA first tried to reset the PCU. When that did not work, it switched to the backup PCU. This finally worked and the telescope restarted immediately.

But, this isn’t the first time that the Hubble has had this issue. Around 13 years ago, the Command Unit module failed. NASA sent astronauts on a spacewalk to fix Hubble and they successfully replaced the Command Unit module.

Time has its effect on technological gadgets and as it gets older, it degrades. Hubble has done its job well, and we can’t wait to see what other great views of the universe it shows us next!