Perhaps no space mission has revealed as many wonders of the universe as the Hubble Space Telescope has. From its perch about 350 miles above Earth, the space observatory has produced sharp, mesmerizing views of planets, stars, and galaxies. The Hubble Deep Field, one of the most iconic images in astronomy, captured thousands of glittering galaxies in a tiny piece of the sky. Beyond the pretty pictures, the telescope has provided scientists with an immense amount of information about the history of the cosmos.
But Hubble isn’t a spring chicken anymore. The telescope was originally supposed to retire after 15 years in space. It turned 28 this year, and the signs of aging are beginning to show.
Last week, NASA engineers put Hubble in “safe mode,” a state that precludes science observations, after a device that helps keep the observatory steady failed. Hubble usually employs these devices, known as gyroscopes, to orient itself in space and point at different targets astronomers want to observe. (Hubble’s instruments and other systems are fine.) About a decade ago, Hubble had six operating gyroscopes. Now it’s down to two.
NASA said it had expected this particular gyroscope to break down around this time, based on the predicted lifespan of the hardware. Engineers decided to turn on a backup gyroscope while they figured out whether the failed one could be recovered. But the backup gyroscope “did not perform as expected,” NASA announced Friday, and Hubble will remain in safe mode while engineers continue to troubleshoot. Hubble can still function with only one gyroscope, which would slightly limit its operations, but engineers want to at least try to fix the failed device. To investigate potential remedies, NASA has convened a review board of Hubble operations managers, engineers, and industry professionals familiar with the design of this type of gyroscope.