Click here to find out more! Text size: increase text sizedecrease text size Malfunctions on Hubble computer delay service launch

NASA has delayed plans to launch a repair mission to the Hubble Space Telescope because an onboard computer stopped working over the weekend, officials said today.

The mission, planned for launch Oct. 14, is postponed until at least early next year. In the meantime, the telescope is unable to transmit any science data to the ground.

Engineers at the NASA Goddard Space Flight Center in Greenbelt are working this week to transfer the work of Hubble's science data downlink computer repair to a backup system. But the backup has not been tested since Hubble was launched in 1990, and it's uncertain whether the transfer will work, said Susan Hendrix, a spokeswoman for the Hubble program at the Goddard Space Flight Center in Greenbelt.

In either case, NASA officials said, the launch will have to be delayed while engineers assess the problems, test replacement parts and plan for possible attempts to repair or replace the computer.

That will come as an acute disappointment for hundreds of scientists and engineers in Maryland who work with Hubble at Goddard or at the Space Telescope Science Institute in Baltimore.

Hendrix said the problem arose just after 8 p.m. Saturday when "Side A" of the telescope's scientific data downlink computer -- called the Control Unit/Science Data Formatter -- experienced what Hendrix called a "hardware failure."

The telescope went into a "safing" mode, which shut down the scientific instruments.

Side A of the computer has been operating reliably since the observatory was launched in 1990.

"There is a Side B, and they're looking at transitioning to Side B," she said. That would restore the telescope's science observations and downlinks. But the backup hardware hasn't been switched on in more than 18 years in space, and engineers aren't certain it will work.

The changeover requires completing a "transition flight readiness review," and switching five other related devices over to Side B, Hendrix said. And that takes time.

"They're hoping to know something by the end of the week if they can bring up Side B," she said.

NASA was planning for an Oct. 14 launch of the space shuttle Atlantis on a mission to upgrade and repair the observatory.

The long-awaited servicing mission is to be the final visit by astronauts to the orbiting telescope. Their goal is to extend its working life at least another five years, and to expand its power.

The astronauts' work list already includes replacement of batteries and gyroscopes, the installation of two new scientific instruments, and attempts to repair two other instruments that have broken down since the last servicing mission in 2002.

Seven astronauts have been training for more than a year for the $900 million repair mission, and engineers at Goddard have designed more than 150 new tools for the four spacewalkers to use.

Now mission planners will have to decide whether to ask astronauts to attempt to replace the failed computer and restore its redundancy by installing a backup currently in storage on the ground.

If they do, it will require additional testing, planning and training time. NASA already has scheduled five seven-hour spacewalks for astronauts to make a list of repairs and upgrades.

source: http://www.baltimoresun.com/news/nation/bal-hubble0929,0,6468448.story