NASA has said its Chandra space telescope will return to normal operation next week following a major technical problems.
Chandra automatically went into so-called safe mode last Wednesday, because of a gyroscope problem.
Hubble went into hibernation last Friday due to a similar gyroscope failure.
This illustration made available by NASA shows the Chandra X-ray Observatory. On Friday, Oct. 12, 2018, the space agency said that the telescope automatically went into so-called safe mode on Wednesday, possibly because of a gyroscope problem.
Now, NASA said it has fixed the problem on Chandra
‘The cause of Chandra’s safe mode on October 10 has now been understood and the Operations team has successfully returned the spacecraft to its normal pointing mode,’ NASA said.
It claimed the safe mode was caused by a glitch in one of Chandra’s gyroscopes resulting in a 3-second period of bad data that in turn led the on-board computer to calculate an incorrect value for the spacecraft momentum.
The erroneous momentum indication then triggered the safe mode.
‘The team has completed plans to switch gyroscopes and place the gyroscope that experienced the glitch in reserve,’ NASA said.
‘Once configured with a series of pre-tested flight software patches, the team will return Chandra to science operations which are expected to commence by next week.’
Both orbiting observatories are old: Hubble is 28, while Chandra is 19. Flight controllers are working to resume operations with both.
NASA says it’s coincidental both went ‘asleep’ within a week of one another.
It ‘continues to work toward resuming science operations of the Hubble Space Telescope after the spacecraft entered safe mode due to a failed gyroscope (gyro) on Friday, Oct. 5.’
An astronomer who works on Chandra, Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics, tweeted Friday that ‘Chandra decided that if Hubble could have a little vacation, it wanted one, too.’
‘At approximately 1355 GMT on October 10, 2018, NASA’s Chandra X-ray Observatory entered Safe Mode, where the telescope’s instruments are put into a safe configuration, critical hardware is swapped to back-up units, the spacecraft points so that the solar panels get maximum sunlight, and the mirrors point away from the Sun,’ NASA said.
‘Analysis of available data indicates the transition to safe mode was nominal, i.e., consistent with normal behavior for such an event.
‘All systems functioned as expected and the scientific instruments are safe. The cause of the Safe Mode transition is currently under investigation.’
The Hubble Space Telescope was been sidelined by a serious pointing problem.
NASA announced that one of Hubble’s gyroscopes failed last Friday.
As a result, Hubble is in so-called safe mode with non-essential systems turned off, putting all science observations on hold.
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. The Hubble Space Telescope has been sidelined by a pointing system failure.
NASA says mission controllers are working to restore the 28-year-old telescope.
Gyroscopes are needed to keep Hubble pointed in the right direction during observations.
‘It’s true. Very stressful weekend,’ Rachel Osten, Hubble’s deputy mission head at the Space Telescope Science Institute in Baltimore, said on Twitter.
‘Right now HST is in safe mode while we figure out what to do.
‘Another gyro failed.
‘First step is try to bring back the last gyro, which had been off, and is being problematic.’
Launched in 1990, Hubble has had trouble with its gyroscopes before.
Spacewalking shuttle astronauts replaced all six in 2009.
The telescope could work with as few as one or two gyroscopes, although that leaves little room for additional breakdowns.
Olsten confirmed the problem would not mean the end of Hubble.
‘Not really scary, we knew it was coming.
‘The gyro lasted about six months longer than we thought it would (almost pulled the plug on it back in the spring).
‘We’ll work through the issues and be back.’
Even with one gyro working , Hubble will still be able to take part in science, NASA confirmed.
‘There isn’t much difference between 2- and 1, and it buys lots of extra observing time. Which the Astro community wants desperately.’
Astronomers use the orbiting observatory to peer deep into the cosmos, revealing faraway solar systems as well as galaxies and black holes.