Final space shuttle mission delayed two months

CAPE CANAVERAL - It looks like the space shuttle program's last flight will slip two months to November, thanks to delays with one of the final pieces for the space station.

Shuttle Discovery had been slated to make the fleet's final flight in September. But Endeavour's final flight, previously planned for July, has been bumped until at least November, leapfrogging Discovery's mission.

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NASA did not announce a specific date for Endeavour's flight, which will deliver the Alpha Magnetic Spectrometer to the space station. Concerns about an electromagnet aboard the $1.5-billion physics experiment have prompted scientists to replace that part with a traditional magnet.

The move should extend the lifetime of the spectrometer, scientists say, though critics of the move say it will make the tool -- which is designed to look for antimatter and dark matter -- less effective.

NASA is using the last few shuttle flights to finish and equip the international space station. A presidential directive issued under the Bush administration ordered the agency to retire the shuttle by this September. But the Obama administration, while supporting the retirement, has authorized $600 million to carry the last flights beyond that deadline, if necessary.

The next flight, scheduled for May 14, will be Atlantis' final flight.