NASA is grounding future space shuttle flights because foam debris like the kind that brought down Columbia is still a risk. A pretty big piece of the foam insulation came off Discovery's fuel tank during Tuesday's liftoff. Luckily it didn't hit the orbiter.
A NASA spokesman says there's no threat to the seven astronauts. Unfortunately, this grounding is a tremendous setback to our space program, which has spent 2 1/2 years trying to overcome the Columbia disaster.
"We're so lucky this happened after the solid rocket motors detached," said Chuck Watson of Savannah, who consults for the space administration. "A few seconds earlier and the way the air currents flow around the tank, it would have dragged the piece and flown it into the orbiter at six, seven hundred miles per hour."
Watson says he thinks it's time that NASA puts all its efforts into designing a new shuttle rather than trying to tinker with the current model, which is based on technology from the 1970s.