The newest, most powerful space telescope out there is back to work after a glitch blocked several days' worth of science observations.
Mission personnel behind the James Webb Space Telescope (Webb or JWST) spent about two weeks battling a glitch that first appeared on Dec. 7, according to a NASA statement (opens in new tab). According to NASA officials, the glitch never threatened the telescope, and normal operations resumed on Tuesday (Dec. 20).
"The observatory and instruments are all in good health, and were not in any danger while Webb's onboard fault management system worked as expected to keep the hardware safe," NASA officials wrote.
JWST will mark one full year in space on Sunday (Dec. 25). It began science operations in July. Previously this year, the observatory has faced two other issues: In May, a micrometeoroid impact caused a little more damage than environmental models had predicted was likely, and in August the observatory's Mid-Infrared Instrument (MIRI) experienced an issue with one of its four observing modes.
However, the recent issue appears to be the first that has paused all science operations, across the observatory.
According to NASA, the trouble began on Dec. 7, when JWST's attitude control system, which keeps the observatory protected from the sun and able to reach Earth, experienced a software glitch. The glitch sent the telescope into safe mode, a state in which a spacecraft turns off nonessential systems and hunkers down in a stable configuration while waiting for engineers to investigate an issue.
The observatory entered safe mode and recovered from it multiple times in the following days, the NASA statement implies.
"This event resulted in several pauses to science operations totaling a few days over that time period," officials wrote. "Science proceeded otherwise during that time." (The observations JWST missed will be rescheduled where possible, officials noted.)
The issue is now under control, according to the statement, after mission personnel "adjusted the commanding system." Normal operations resumed on Tuesday (Dec. 20), just in time for the telescope to mark its first anniversary in space.