Several thousand NASA contractors in Florida and Louisiana could be out of work once the space shuttle flies its last mission in 2010, the head of the U.S. space agency told a Senate panel Feb. 27.

NASA Administrator Mike Griffin said Florida's Kennedy Space Center stands to lose "several thousand" contractor jobs following the space shuttle's retirement from service.

While some of those jobs will return as NASA begins flying the space shuttle's successor — the Orion Crew Exploration Vehicle and the Ares 1 rocket — the new system, by design, is expected to require fewer people to operate than the labor-intensive space shuttle.

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Orion and Ares are not expected to begin operations until early 2015, although flight tests out of the Kennedy could begin a few years earlier.

The space shuttle program employs roughly 14,000 people at Kennedy Space Center in Florida. Griffin said Kennedy would need to take on new roles and responsibilities beyond launch operations if it wants to maintain it current workforce levels post-shuttle.

NASA's Michoud Assembly Facility in New Orleans also is expected to be hard hit by the shuttle's looming retirement. The contractor-operated facility produces external fuel tanks for the shuttle.

As tank work winds down in the years just ahead, NASA employment "will drop from about 1,900 today to under 600, somewhere down around 500 for a time before coming back up," Griffin told the Senate Commerce space and aeronautics and related sciences subcommittee during a hearing on NASA's 2009 budget request.

NASA and its contractors plan to use Michoud to produce parts of Orion and Ares, but that production activity is expected to remain fairly limited until the new system begins making regular flights.

Griffin's numbers did not sit well with Sens. Bill Nelson (D-Fla) and David Vitter (R-La.), the two lawmakers presiding over the hearing. Nelson is the subcommittee's chairman and Vitter is the subcommittee's ranking Republican.

Nelson asked Griffin whether Johnson Space Center in Houston and Marshall Space Flight Center in Huntsville also stand to lose jobs once the shuttle retires.

"Will other centers feel the pain? How about Johnson? How about Marshall?" Nelson asked.

"Broadly speaking I don't think we are going to have significant overall workforce reductions at [Johnson Space Center] or Marshall," Griffin said.

Johnson is NASA's lead center for the Constellation Program, which encompasses Orion, Ares and the other systems needed to send astronauts to the Moon. Marshall, meanwhile, has lead responsibility for designing Ares.

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