NASA has suspended all manned space flights, until it finds out why shuttle Columbia broke apart in the sky high above (the state of) Texas Saturday, minutes before it was scheduled to land, killing all seven astronauts aboard.
Shuttle program manager Ron Dittemore says everything appeared routine, as Columbia was returning to Earth for a touchdown at Cape Canaveral in Florida to complete its 16-day mission in space.
(Speaking to reporters at the Johnson space center in Houston, Texas) Mr. Dittemore said sensors that measure temperature, tire pressure and structural heat suddenly failed on the shuttle's left wing. A few minutes later, communication with the astronauts was lost.
At about the same time, loud booms echoed across eastern Texas, shaking buildings and frightening residents. Millions of people around the world watched on television as Columbia, moving at 18 times the speed of sound, broke into pieces.
Bright flashes of light and plumes of smoke streaked across a crystal-blue sky, and debris from the shuttle began falling more than 60 kilometers down to Earth.
Hours later, President Bush, in a broadcast from the White House, formally announced the tragedy to a shocked and grieving nation.
NASA says it is too early to say what caused the disaster -- the worst since the shuttle Challenger exploded on lift-off 17 years ago, killing all seven crewmembers on board.
During Columbia's launch last month, the space agency said, a piece of foam insulation came off a fuel tank and struck the shuttle's left wing. Experts studied the incident at the time but concluded that it posed no safety risk.
U.S. officials were quick to rule out the possibility of terrorism, saying Columbia was far beyond the range of any missile.
Information for this report is provided by AP, AFP and Reuters.