The US space agency NASA has said it is grounding the fleet of the Space Shuttle. During the liftoff of the shuttle Discovery on Tuesday, a large piece of foam insulation broke off the fuel tank. A spokesperson said that future flights are on hold until the problem is corrected. NASA said, however, that it appeared the insulation breakoff didn't damage the orbiter of the Discovery, which is now in space.

This week, Discovery was the first shuttle to fly since the Columbia disintegrated upon re-entry into the earth's atmosphere two and half years ago. The cause then was a piece of insulation that broke off during takeoff and caused a gash in the orbiter's wing.