Two space shuttle facilities have been damaged by Hurricane Katrina and hundreds of workers are homeless.

NASA is reassessing the prospects of a possible March launch for shuttle Discovery.

NASA could repair fuel tanks at Kennedy Space Center in Florida, as opposed to the hurricane-damaged Michoud Assembly Facility in New Orleans, where the tanks are made.

NASA's Stennis Space Center near Bay St. Louis, Miss., where shuttle main engines are tested, also suffered storm damage.

The space agency estimates Katrina caused at least $1 billion in damage at those facilities.

At Michoud, Lockheed Martin has been able to contact only half its 2,000 employees.

At Stennis, almost all 1,800 employees have been accounted for, but about 200 are without homes.

Discovery flew a mission in July and August to resupply the international space station and test out new procedures for detecting and repairing damage similar to what caused the destruction of Columbia two years earlier.

But insulating foam peeled from the external fuel tank during launch -- the same problem that doomed Columbia -- leading NASA to ground flights until the problem can be fixed.