More than 8,500 NASA jobs are threatened with the planned retirement of the space shuttle in 2010.

NASA announced the cuts Tuesday and said they are expected to hit the Kennedy Space Center the hardest. NASA could lose nearly 6,500 contractors at the space center and about 1,500 elsewhere. About 600 civil service employees could be cut, the agency said.

NASA Associate Administrator William Gerstenmaier cautioned that the figures on NASA job cuts are preliminary.

He said some of the employees could be moved to new positions created by the Constellation program, which will build new spacecraft and equipment for trips to the International Space Station, the moon, and Mars. Others could gain private employment through companies that work with NASA.

NASA had to report the job loss estimates because Congress requires a forecast every six months.

The "Workforce Transition Strategy Initial Report" reveals that NASA is 33% confident it will be able to prepare the next manned spaceflight vehicle, Constellation, for flight by 2013. The agency said it is 65% confident it will be ready for a launch in 2015.

"This means that even if this massive project experiences no delays or unforeseen issues, the minimum time that America will be shut out of space is five years," U.S. Rep. Dave Weldon, R-Fla., said in a statement. "This report seems to reflect the increased likelihood that the gap could actually widen beyond five years. This comes as China is working feverishly to surpass U.S. space dominance and as Russia is becoming increasingly hostile."

Weldon is cosponsoring a bill (H.R. 4837) with Rep. Tom Feeney, R-Fla., to add funding and continue shuttle operations for two missions per year through the five-year gap.