NASA's gamma-ray observatory is in safe mode after a possible wheel failure

A visualization of the Neil Gehrels Swift Observatory.  (Image credit: NASA)

NASA's Neil Gehrels Swift Observatory has temporarily stopped its science observations while the mission team investigates an issue.

On Tuesday night (Jan. 18), the observatory, a gamma-ray hunting space telescope originally called the Swift Gamma-Ray Burst Explorer, went into safe mode and paused all science work. This maneuver may have been in response to a reaction wheel failure, which the mission team continues to explore. 

Swift uses a total of six reaction wheels to autonomously point itself in the direction of possible gamma-ray bursts (GRBs). When the observatory detected the issue this week, it turned off the problematic wheel was turned off, according to a statement from NASA. This is the first reaction wheel failure in the telescope's 17 years of operating in space.

Related: Record-breaking gamma-ray burst captured by Fermi

While the team continues to work on the suspected failure of the sixth wheel, mission personnel also hope to get Swift's science instruments back up and running with just five wheels, the statement noted. 

Swift launched to space in 2004, having been named for the mission's principal investigator Neil Gehrels, who died in 2017. The space telescope lifted off on a mission to study gamma-ray bursts, incredibly energetic explosions in faraway galaxies. The short-lived bursts are the most energetic form of light, according to NASA, and can last anywhere from mere milliseconds to hours. 

Astronomers think they could originate from supernova explosions or from collisions between neutron stars, the dense remnants of supernovas. The spacecraft was sent to observe and study these bright phenomena, which scientists are still working to understand. 

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Chelsea Gohd
Senior Writer

Chelsea “Foxanne” Gohd joined in 2018 and is now a Senior Writer, writing about everything from climate change to planetary science and human spaceflight in both articles and on-camera in videos. With a degree in Public Health and biological sciences, Chelsea has written and worked for institutions including the American Museum of Natural History, Scientific American, Discover Magazine Blog, Astronomy Magazine and Live Science. When not writing, editing or filming something space-y, Chelsea "Foxanne" Gohd is writing music and performing as Foxanne, even launching a song to space in 2021 with Inspiration4. You can follow her on Twitter @chelsea_gohd and @foxannemusic.