Spacecraft controllers are still working on a faulty computer memory system on NASA’s Hubble Space Telescope, which has forced the telescope to shut down for nearly a week.
A payload computer on Hubble stopped working on June 13, the agency said in a statement on June 16. Engineers thought that the computer utilized to manage Hubble’s science instruments’ operations failed due to a failing memory module, putting the instruments in a safe mode. The agency told at the time that it would turn off a backup memory module that day and restart the instruments and resume science observations after about a day of testing.
However, NASA stated on June 18 that the efforts to switch to a backup memory module failed because “the command to initiate the backup module failed to complete.” Attempts to restore the computer using both the original memory module and the backup unit were also unsuccessful.
NASA did not elaborate on the next steps it will take to resolve the issue, only stating that the operations team “will be running tests and collecting more information on the system to isolate the problem further.” The instruments, as well as the rest of the telescope, are in good condition.
The payload computer system from the 1980s can use four memory modules, each containing 64 kilobytes of complementary metal-oxide-semiconductor memory. There is also a backup computer.
This is not Hubble’s first technical snafu. The space telescope was launched 31 years ago and was last serviced by the space shuttle 12 years ago. In March, a problem related to a recent software “improvement” uploaded to the telescope put it in a safe mode for several days. In October 2018, a faulty gyro knocked the telescope offline for three weeks.
“There are anomalies. What happens when you have a decades-old observatory, but we were able to resolve those anomalies,” Nancy Levenson, deputy director of the Space Telescope Science Institute, said during a town hall session at the American Astronomical Society’s 238th Meeting on June 8.
She emphasized that the telescope was performing well in general and was still in high demand among astronomers. The institute manages Hubble’s science operations and, soon, the James Webb Space Telescope plans for Hubble’s extended operations.
“We’re still planning for the very long term,” she said. She cited “COS 2030,” a program to extend the life of the Cosmic Origins Spectrograph, an instrument installed on Hubble during the final servicing mission in 2009, until the end of the decade.