Hubble Revival Halted Due to Unforeseen Glitch
for National Geographic News
|October 17, 2008|
Efforts to restore science operations aboard the Hubble Space Telescope came to a screeching halt late yesterday, when engineers ran into an as-yet undisclosed glitch.
A team of about 50 NASA engineers and scientists have been working around the clock since Wednesday at the Goddard Space Flight Center in Greenbelt, Maryland, to remotely switch to a backup data formatter.
The primary formatter, which sends information from Hubble to Earth, failed on September 27, rendering the telescope virtually mute.
"We experienced an issue late yesterday on Hubble that we're still troubleshooting," Goddard spokesperson Ed Campion told National Geographic News Friday morning.
"We've stopped trying to activate science."
Earlier this week, Hubble team leaders were optimistic that Hubble would be powered back up this morning following several days of "safe mode" operations.
During the temporary shutdown, engineers were to send Hubble hundreds of commands to bypass the faulty data formatter and utilize the backup, called side B.
As of Thursday, the plan was flowing smoothly.
"During the night of Oct. 15, Space Telescope Operations Control Center engineers at NASA's Goddard Space Flight Center turned on and checked out Side B of Hubble's Science Instrument Control and Data Handling (SIC&DH) system," said an update on the Hubble Web site.
Several cameras were checked to confirm they were connected to the new formatter and then sent back into safe mode.
Starting at noon on Thursday, engineers began testing Hubble's science instruments one by one and calibrating them. Sometime during that stage, the latest glitch hit.
Goddard's Campion said details about what happened will be forthcoming throughout the day.
Even if the repairs had gone as planned, switching to the backup formatter involves some risk.
The device has been exposed to the same cyclic heat stress that may have caused the failure of the primary side A instrument. Switching to side B would leave Hubble with no backup should that system fail, too.
But the risk would be temporary, as engineers are beginning tests now on a duplicate data formatter, including both a primary and backup system, that has been stored on Earth since Hubble's 1990 launch.
(See a gallery of Hubble's top ten science discoveries to date.)
Hubble scientists are hopeful that the boxy, 135-pound (61-kilogram) instrument will be tested and ready for transport to the space telescope during the next space shuttle servicing mission.
Originally slated for October 10, the Atlantis shuttle mission to Hubble was postponed until at least February after the formatter failed.
Art Whipple, lead mission systems engineer for Hubble at Goddard, said on Monday that each month of the delay costs the Hubble program about U.S. $10 million.
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