No fourth space walk for Discovery

HOUSTON, Aug. 4 (UPI) -- NASA decided Thursday space shuttle Discovery astronauts will not make a fourth spacewalk to repair a thermal blanket outside the craft.

There had been speculation the crew might be assigned one more chore outside the shuttle to correct the problem, just outside the commander's window. National Aeronautics and Space Administration officials ruled it out because the blanket did not pose a threat to the safety of the mission.

The top of the shuttle is covered with blankets made of heat-resistant fabric -- as opposed to the heat-resistant ceramic tiles that cover the underside of the ship. The top side does is not exposed to the same extreme of hot temperatures as the underside during re-entry.

Space Shuttle Deputy Program Manager Wayne Hale said if the blanket were to come off in one piece there is a relatively low chance that it would strike the orbiter.

"We've assessed this risk to the very best of our engineering knowledge," Hale said, "and we believe the vehicle is safe to fly and for re-entry."

The crew is scheduled to begin packing the shuttle Friday for the return to Earth on Monday.