The space shuttle Endeavour sits on launch pad 39A as work continues on the shuttle's electrical problems

NASA on Sunday delayed the launch of space shuttle Endeavour at least until May 8 as work continues to resolve an electronics problem that scuttled Friday's launch attempt, officials said.
"It's not going to be any earlier than the eighth," said Mike Moses, head of NASA's launch mission management team. "Don't take that as a launch date, take that as a target."

NASA tried to launch Endeavour on Friday on its 25th and final flight to deliver the $2 billion Alpha Magnetic Spectrometer particle detector to the International Space Station, reports Reuters.
A problem with a heating system on one of the ship's hydraulic power generators prompted managers to stop the countdown. The heaters keep fuel from freezing in the line, preventing it from rupturing in the cold vacuum of space.

NASA was hopeful that the problem would have an easy solution and had retargeted Endeavour's launch for Monday, but further trouble-shooting indicated the glitch was more complicated than officials hoped initially.
Endeavour's six astronauts were headed back to the Johnson Space Centre in Houston for a few days of additional training before they return for the next launch attempt, NASA said.

U.S. Representative Gabrielle Giffords, who is married to Endeavour commander, Mark Kelly, was on hand for the launch. But the U.S. space agency said family members of crew members left Cape Canaveral after the fresh delay announced on Sunday.
Giffords, an Arizona Democrat, was gravely injured during an assassination attempt on January 8 and had not been seen publicly since then.

The Endeavour mission is the next-to-last for the 30-year-old shuttle program, which is ending after sister ship Atlantis completes its final voyage this summer.
Endeavour was the replacement ship for Challenger, which was lost in a fatal 1986 launch accident. It is the youngest of NASA's three surviving spaceships and the second to be retired.
Discovery, the fleet leader, returned from its final space mission in March, and Atlantis is due to end the shuttle program with a launch on June 28.