NASA’s 19-year-old Chandra X-ray Observatory has been returned to its normal pointing mode after a data glitch forced a five-day outage, NASA said today.
The bus-sized spacecraft went into safe mode on Oct. 10, bringing science observations to a halt. The Chandra mission’s operation team determined that the outage was caused by a fault in one of the gyroscopes used by Chandra’s pointing system. That fault resulted in a three-second period of bad data, which led the onboard computer to calculate an incorrect value for the spacecraft’s momentum, NASA said in today’s status update.
The erroneous reading triggered the safe-mode condition, which caused Chandra to swap critical hardware operations to backup units and reconfigure its mirrors and solar panels to avoid the risk of damage.
Chandra’s operation team diagnosed the problem and switched gyroscopes to get the pointing system up and running again. The gyroscope that experienced the glitch has been placed in reserve.