Professor and 'Future of Humanity' author explains significance of NASA rover touching down on the Red Planet 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."