Engineers have identified the technical problem that caused the delay of the Endeavour shuttle launch last week, and expect it will take several days to fix, NASA said Monday.
The next launch attempt has not been set, but will be determined in a meeting of mission managers "over the next day or two," NASA said in a statement, reiterating that liftoff would be "no earlier than May 8."
The mission of the shuttle Endeavour is to be the US program's second-to-last flight to the International Space Station, followed by Atlantis in June. After that, the 30-year-old US shuttle program will end.
The glitch, which caused NASA to scrub the attempt hours before liftoff Friday, was traced to a power problem in the aft load control assembly-2 (ALCA-2), a box of switches that control electrical flow to heaters that keep fuel lines from freezing in orbit.
"The plan is to remove and replace the box, but that work and related testing will take several days to complete," NASA said.
"Once the new box is installed, the team must verify it's working properly -- at least a two-day process -- and perform forensics on the failed box."
The six-member crew of astronauts left Florida on Sunday and are engaging in more mission training at NASA's Johnson Space Center in Houston, Texas while they wait for the next launch attempt date to be announced.
Endeavour will carry a $2 billion, seven-ton particle physics detector, the Alpha Magnetic Spectrometer-2, which will be left at the space station to scour the universe for dark matter and antimatter.
The 14-day mission, known as STS-134, is to be commanded by US astronaut Mark Kelly, whose wife, Arizona Congresswoman Gabrielle Giffords, is recovering from a gunshot wound to the head sustained in January.
Giffords was allowed by her rehab doctors in Houston to fly to Florida to watch the launch, and she is expected to return again for the next attempt, her office said.
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