Oct. 20 (Bloomberg) -- The shuttle Atlantis was rolled back from its launch pad in Cape Canaveral, Florida, today as troubles persisted with the Hubble Space Telescope, the destination of a servicing mission now delayed until next year.

Atlantis, which weighs about 4.5 million pounds (2 million kilograms), traveled on a two-story crawler outfitted with tank- like treads. The 3.4-mile (5.5-kilometer) journey from pad to storage building took about six hours, said Candrea Thomas, a spokeswoman at Kennedy Space Center.

Hubble, one of NASA's premier telescopes, has been shuttered since Sept. 27, its longest failure in almost a decade. The Oct. 14 service mission was scrubbed as problems multiplied, requiring repairs the Atlantis crew was untrained to make.

``The head of NASA decided it made sense to delay the mission until we know what's wrong,'' said Susan Hendrix, a spokeswoman at Goddard Space Flight Center in Greenbelt, Maryland.

Voltage and computer glitches may be fixed by the weekend, possibly restoring Hubble to normal, Hendrix said.

The telescope, running on a 486 Intel chip now considered obsolete, is set to receive in-orbit ``surgery'' when astronauts visit sometime next year, NASA said. That includes opening bay doors and pulling out old circuit boards for replacement.

Spacewalkers had already planned to swap batteries, gyroscopes and cameras on the telescope, which is about the size of a school bus, said the National Aeronautics and Space Administration.

Replacement Parts

A data handler has been added to the list of Hubble replacement parts, which may grow. The handler processes images before they're beamed to Earth and is blamed for the initial failure three weeks ago.

NASA's next scheduled shuttle launch is the Endeavour on Nov. 14. The craft will resupply the International Space Station and prepare it to house six people next year, double the usual crew.

The orbiting outpost is about two-thirds built after two science labs were added in the past year. The Endeavour will deliver a second toilet, extra sleeping quarters and exercise equipment during its 15-day mission.

Endeavour's astronauts will also make spacewalks to service rotating gears that help the station's solar panels follow the sun.

To contact the reporter on this story: Demian McLean in Washington at dmclean8@bloomberg.net.

Last Updated: October 20, 2008 15:21 EDT