The Hubble Space Telescope, earth’s eye into the universe for more than 30 years now, has been down for the past few days, NASA revealed on Friday.

The US space agency said that the problem arose when a  payload computer stopped working last Sunday but insisted that the telescope and its instruments are fine.

“The payload computer’s purpose is to control and coordinate the science instruments and monitor them for health and safety purposes,” NASA said.

An attempt to restart it on Monday failed.

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NASA said initial evidence pointed to a degrading computer memory module as the source of the computer problem.

An attempt to switch to a backup memory module also failed.

The technology for the payload computer dates back to the 1980s, and it was replaced during maintenance work in 2009.

Launched in 1990, the Hubble Space Telescope revolutionized the world of astronomy and changed our vision of the universe as it sent back images of the solar system, the Milky Way, and distant galaxies.

A new and more powerful one, called the James Webb Space Telescope, is scheduled to be deployed late this year. It is designed to peer deeper into the cosmos than ever before.