The Hubble Space Telescope went into safe mode on Friday, when the failure of one of its gyroscopes, and the reduced performance of another, put it on hiatus while NASA troubleshoots. "The one thing the Hubble team has shown time and again is it's resilient, and the observatory is very robust to these kinds of things".
Astronomers have been hoping that Hubble will continue to operate long enough to cover the transition to NASA's next-generation James Webb Space Telescope.
Hubble has six gyroscopes it uses to point itself and keep itself steady for observations.
Hubble has made more than 1.3 million observations since its mission began in 1990 and helped publish more than 15,000 scientific papers. The space agency said that they tried powering up a reserve gyroscope, but their telemetry indicated that "it was not performing at the level required for operations".
Three of the gyros are older models that have a history of trouble after 50,000 hours or so of service.
Most of the giant Hubble Space Telescope can be seen as it is suspended in space by Discovery's Remote Manipulator System (RMS) following the deployment of part of its solar panels and antennae. It's been peering into the depths of space for almost three decades now, and while it's had a few hiccups in the past, it's always managed to push through them and continue providing humanity with incredible observations.
The deputy mission head for the Hubble Space Telescope (HST), Dr Rachel Osten, confirmed a rumour on Twitter that it was now in safe mode - potentially for weeks - following a gyro failure. But when the third one was powered up, it wasn't operating as it should be, so NASA Goddard engineers placed the telescope in safe mode while they try to figure out the problem.More news: Storm Callum: Amber weather alert issued for Wales
NASA was quick to offer reassurance: "Hubble's instruments still are fully operational and are expected to produce excellent science for years to come", public affairs officer Felicia Chou wrote in an update on the NASA website.
Sembach said everyone wants to be careful in attempting a fix.
Two of the enhanced gyros are now running.
The Hubble Space Telescope has been sidelined by a serious pointing problem.
"So things closer in in the solar system than, say, the orbit of Mars, that would be more hard", he said.
But that doesn't mean it's time to panic. In addition, Hubble would have to rely more on its star trackers and magnetometers to determine its orientation and aiming, effectively reducing the amount of sky it could "see" at any given moment.