Even the backup computer of the Hubble Telescope is glitching now

For nearly two weeks, NASA has been trying to figure out what’s wrong with the Hubble Space Telescope, but the mystery has only grown. Hubble is the world’s most powerful space telescope, having been deployed into orbit in 1990. It has taken images of star births and deaths, discovered new moons orbiting Pluto, and followed two interstellar objects through our solar system. Astronomers have used Hubble’s observations to determine the universe’s age and expansion, as well as gaze into galaxies, formed just after the Big Bang.

However, the Earth-orbiting observatory has been inactive for the past 12 days. On June 13, the payload computer for the telescope – a 1980s processor that controls and monitors all of the spacecraft’s science instruments – stopped working.

Since then, NASA’s Hubble crew has been troubleshooting. Even if they couldn’t restore the computer, the scientists concluded, they could always switch to Hubble’s backup payload computer. However, NASA realized this week that the backup computer was also malfunctioning. As a result, it’s on the lookout for a fresh explanation for Hubble’s mysterious issues.

NASA tried but failed, to restart the payload computer. The team then focused on a memory module that had been deteriorating and was recording errors. The Hubble crew speculated that this would be the source of the problem, but they were unsuccessful. The memory module, as well as one of its three backups, were both unusable. That meant the problem was coming from further upstream.

This week, the team started doing diagnostic tests on additional portions of the payload computer. They also opted to turn on the backup payload computer, which had been off since astronauts mounted it on the telescope in 2009. However, the new computer had the same problems as the old one, with the same hardware.

This suggests that the payload computer isn’t the issue after all. It’s most likely another system further upstream. “Because it’s highly unlikely that all individual hardware parts have a problem,” NASA said in a blog update on Friday.