HOUSTON - Space shuttle Columbia began losing pieces over the California coast well before it disintegrated over Texas, the accident investigation board reported yesterday, finally confirming what astronomers and amateur skywatchers have been saying from Day One.
But board member James Hallock, a physicist and chief of the Transportation Department's aviation safety division, said the fragments were probably so small they burned up before reaching the ground.
He said the conclusion that the space shuttle was shedding pieces a full six minutes before it came apart over Texas was based on images of the doomed flight. Astronomers and amateurs on the West Coast photographed and videotaped the shuttle's final minutes.
"Obviously, it would be very important to understand what those pieces are, particularly the ones that started falling off at the very beginning," he said.
But Hallock said the pieces that came off early did not seem to be very big, judging from the light reflected off of them.
"For us to find something that far back along the path, I think it's going to have to be a pretty substantial piece of the shuttle itself," he said.
Moreover, he added: "That's a lot of area to be looking. ... We have the Grand Canyon area and all of the areas of Southern California, the mountainous area and stuff like this, that even if we could home in on some of these things, it's going to be very difficult to find it. But we sure would like to see it."
In their second news conference in as many weeks, the board members also said they are not convinced the debris that hit the left wing shortly after liftoff Jan. 16 was insulating foam from the external fuel tank. It is possible the debris was actually ice or much heavier insulating material behind the foam, they said.
Hallock said the suspected breach in Columbia's left wing had to have been bigger than a pinhole to allow the superheated gases surrounding the ship to penetrate the hull.
The board also announced that it hopes to hold its first public hearing next week, possibly Feb. 27, to listen to non-NASA experts who have theories about what destroyed the shuttle.
The newest member of the 10-member panel, former Air Force Secretary Sheila E. Widnall, will join her colleagues this week.
Additional members are being sought to include more scientific experts and quell criticism from members of Congress who contend the board is not independent enough of NASA.
But board member James Hallock, a physicist and chief of the Transportation Department's aviation safety division, said the fragments were probably so small they burned up before reaching the ground.
He said the conclusion that the space shuttle was shedding pieces a full six minutes before it came apart over Texas was based on images of the doomed flight. Astronomers and amateurs on the West Coast photographed and videotaped the shuttle's final minutes.
"Obviously, it would be very important to understand what those pieces are, particularly the ones that started falling off at the very beginning," he said.
But Hallock said the pieces that came off early did not seem to be very big, judging from the light reflected off of them.
"For us to find something that far back along the path, I think it's going to have to be a pretty substantial piece of the shuttle itself," he said.
Moreover, he added: "That's a lot of area to be looking. ... We have the Grand Canyon area and all of the areas of Southern California, the mountainous area and stuff like this, that even if we could home in on some of these things, it's going to be very difficult to find it. But we sure would like to see it."
In their second news conference in as many weeks, the board members also said they are not convinced the debris that hit the left wing shortly after liftoff Jan. 16 was insulating foam from the external fuel tank. It is possible the debris was actually ice or much heavier insulating material behind the foam, they said.
Hallock said the suspected breach in Columbia's left wing had to have been bigger than a pinhole to allow the superheated gases surrounding the ship to penetrate the hull.
The board also announced that it hopes to hold its first public hearing next week, possibly Feb. 27, to listen to non-NASA experts who have theories about what destroyed the shuttle.
The newest member of the 10-member panel, former Air Force Secretary Sheila E. Widnall, will join her colleagues this week.
Additional members are being sought to include more scientific experts and quell criticism from members of Congress who contend the board is not independent enough of NASA.