Orlando, Fla. ? NASA is unable to find about 1,000 workers from the Michoud Assembly Facility east of New Orleans where the space shuttles’ external fuel tanks are built.

The damage to Michoud and another Gulf Coast NASA center will cost the agency about $1.1 billion as it tries to repair buildings and find homes for those who lost everything when Hurricane Katrina hit Aug. 29, Bill Gerstenmaier, a NASA associate administrator, said Thursday.

The crisis at Michoud and Stennis Space Center in Bay St. Louis, Miss., is a major setback to the space shuttle program, already troubled by safety concerns following last July’s launch of Discovery.

Gerstenmaier could not say when the next shuttle launch might take place.

The actual physical damage to Stennis and Michoud doesn’t appear too serious, said Bill Parsons, the NASA official in charge of hurricane recovery. The $1.1 billion estimate, he said, includes both repair work and the cost of helping families regroup.