Updated from 12:32 p.m. EST
NASA has named a retired Navy admiral who helped investigate the USS Cole terrorist bombing to lead an independent investigation of the space shuttle Columbia disaster. The Columbia broke up over Texas yesterday, 15 minutes before its scheduled landing in Florida. All seven astronauts on board were killed.
Harold W. Gehman Jr. will lead a government commission that will sift through the Columbia wreckage being gathered from across Texas and Louisiana and trucked under tight security to an Air Force base for analysis.
"We're securing all the debris and assuring that we look at every possible angle of what could have caused this horrible accident,'' NASA chief Sean O'Keefe said.
Remains from the seven astronauts have been found. Officials said that the debris being collected from Texas and Louisiana is being sent to Barksdale Air Force Base in Louisiana for inspection and analysis.
The space shuttle Columbia disintegrated Saturday after losing contact with NASA about 15 minutes before it was scheduled to land at the Kennedy Space Center in Florida. NASA was focusing on a temperature sensor failure as a possible cause.
"These men and women assumed great risk in the service to all humanity," President Bush said in Washington Saturday afternoon, "knowing they had a high and noble purpose in life."
"The crew of the shuttle Columbia did not return safely to Earth, yet we can pray that all are safely home," he said.
One area investigators may look at is possible damage to heat-resistant tiles on the left wing, which NASA officials said had been struck by insulation that broke free on liftoff on Jan. 16. NASA said the first sign of trouble Saturday was the loss of temperature sensor readings in that wing. The insulation apparently hit the bottom of the wing.
Columbia's crew included Col. Rick D. Husband of the Air Force, its commander; the mission pilot, Cmdr. William C. McCool of the Navy; Lt. Col. Michael P. Anderson of the Air Force, who was the payload commander in charge of the science equipment; Dr. Kalpana Chawla, an aerospace engineer; two Navy doctors, Capt. David M. Brown and Cmdr. Laurel Salton Clark, and Col. Ilan Ramon, Israel's first astronaut.
NASA repeatedly tried to reach the shuttle, which was concluding a 16-day mission. But the Columbia did not answer, and its 9:16 a.m. Eastern landing time passed with no sign of the shuttle.
Columbia, whose first flight was in 1981 and had logged more than two dozen spaceflights, disintegrated about 38 miles up as it headed toward the scheduled conclusion of its mission.
Sean O'Keefe, the NASA administrator, said safety officials from other federal agencies and the military had been named to investigate.
"We have no indication that the mishap was caused by anything or anyone on the ground," O'Keefe said in a news conference.
NASA's Web site noted contact had been lost with the shuttle during its descent and warned against anyone picking up debris that it said might be found in East Texas area.
At 9 a.m., Mission Control lost all data and contact with the crew. At the same time, residents in eastern Texas reported hearing "a big bang,"
The Associated Press
Television footage showed a bright light over Texas followed by smoke plumes in the sky. Debris appeared to break off into separate balls of light as it continued downward.
Residents of Nacogdoches, Texas, said they found bits of metal strewn across the city. Dentist Jeff Hancock said a metal bracket about a foot long crashed through his office roof.
"It's all over Nacogdoches," barber shop owner James Milford told the
. There are several little pieces, some parts of machinery ... there's been a lot of pieces about 3 feet wide."
Two hours after the shuttle had been expected to land, the giant screen at the front of Mission Control showed a map of the Southwest U.S. and what should have been Columbia's flight path.
It was the 113th flight in the shuttle program's 22 years and the 28th flight for Columbia, NASA oldest shuttle.
On Jan. 28, 1986, space shuttle Challenger exploded shortly after liftoff.
The shuttle is essentially a glider during the hour-long decent from orbit and is covered by about 20,000 thermal tiles to protect against temperatures as high as 3,000 degrees.
The shuttle was at an altitude of about 203,000 feet over north-central Texas at 9 a.m., traveling at 12,500 mph.
Gary Hunziker in Plano, Texas, said he saw the shuttle flying overhead. "I could see two bright objects flying off each side of it," he told The Associated Press. "I just assumed they were chase jets."
"The barn started shaking and we ran out and started looking around," Benjamin Laster of Kemp, Texas, told the
. "I saw a puff of vapor and smoke and saw big chunk of material fall."