UPDATE: NASA now says "Foam Might Have Struck Discovery."
NASA grounded the space shuttle fleet on Wednesday after determining that a large piece of insulating foam had broken off Discovery's external fuel tank shortly after liftoff Tuesday morning:
"Until we fix this, we're not ready to go fly again," William W. Parsons, the manager of the shuttle program, said at a news briefing at the Johnson Space Center here on Wednesday evening.
According to the New York Times, Discovery's foam incident occurred two minutes after the launch, at a point where the atmosphere is so thin that the piece drifted away. The Columbia accident occurred in part because the foam fell off the tank about 82 seconds after liftoff, when the air was much thicker and slowed the foam so the climbing orbiter struck it with great force:
N. Wayne Hale, the deputy manager of the shuttle program, said that if the Discovery foam had been shed earlier, "we think that it would have been really bad."
How very disappointing and extremely fortunate.
The photos are handheld still images taken by Discovery's crew of the external fuel tank as it was jettisoned after launch on July 26. Initial analysis of the imagery shows a large piece of foam that separated from the tank during the Shuttle's ascent to orbit. The foam detached from an area of the tank called the Protuberance Air Load (PAL) Ramp. This debris also was identified during ascent from a live video camera mounted on the external tank. The television view indicated the debris did not impact Discovery. In this still image, the area of missing foam on the tank is indicated by a light spot near the upper edge of the tank just below the liquid oxygen feedline. (Image Credit: NASA)