NASA's Hubble Space Telescope goes into 'safe mode' after software error

NASA said the instrument is in good condition

NASA's Hubble Space Telescope (HST) went into "safe mode" on Sunday after what the agency said was a "software error."

NASA announced the glitch in a Sunday tweet, writing, that at approximately 4 a.m. ET, the HST "went into safe mode due to an onboard software error."


"The Hubble Space Telescope is in good condition but remains in safe mode as a precaution while the team works to fully understand the error encountered on Sunday and the associated safe mode response," NASA told Fox News on Tuesday. "The team is working to return Hubble back to science operations as soon as possible."

Safe mode is a setting that puts the telescope into a "stable configuration that suspends science observations" and positions the HST's solar panels toward the sun to make sure its energy requirements are met. 

"The spacecraft remains in this configuration until ground control can correct or compensate for the issue," NASA explained in an article in 2018. "The rest of the spacecraft and its instruments are still fully functional and are expected to produce excellent science for years to come."

NASA's Hubble Space Telescope maintains its orbit around Earth. (NASA)

This is not the first time the telescope has entered safe mode.

On Oct. 5, 2018, the spacecraft entered safe mode due to a failed gyroscope and on Jun. 15, 2009, the HST Science Instrument Command and Data Handler (SI C&DH)  began to send unexpected "zero" readings to the on-board HST 486 computer prompting safe mode to activate.

It remains unclear how long it will take to restore functionality this time.

In 2018, HST's safety measures were in place for three weeks before the team was able to revive the telescope. 


A joint venture between NASA and the European Space Agency, the HST launched into orbit in April 1990 aboard the space shuttle Discovery.

Since then, the telescope has delivered amazing images of the universe with more than 1.4 million observations over the course of its lifetime.