The U.S. space agency NASA has suspended all space shuttle flights until investigators can determine why the space shuttle Columbia broke apart over Texas Saturday. The United States and much of the world are reacting with shock and sorrow to the loss of Columbia and its seven crew members.
The shuttle Columbia was only minutes from its planned landing in Florida when something caused it to break apart in the skies over Texas.
Texan Larry Watley had watched the shuttle land before, but this time he noticed something different, a massive fireball immediately behind the orbiter.
"It was going behind the shuttle," he recalled. "I mean, you could definitely see it was falling. And then once I quit watching that [the fireball], I went back to the shuttle again and it was almost out of sight and you could see just tons of little fireballs coming off."
Other eyewitnesses in Texas, Arkansas and Louisiana also reported seeing flames and debris falling to the ground after hearing a loud bang in the sky.
At about the same time, Mission Control in Houston reported that it had abruptly lost voice and data contact with Columbia:
"Communications were lost at approximately 8 a.m. Central Time this morning as Columbia was at an altitude of approximately 200,000 feet [60,000 meters] traveling at a speed of about 12,500 miles an hour [20,000 kilometers]."
A short time later, President George W. Bush confirmed the worst in a brief statement from the White House. "This day has brought terrible news and great sadness to our country. The Columbia is lost. There are no survivors," he said.
Space agency officials were stunned and told reporters that there was no immediate indication as to what caused the shuttle to break up in flight.
NASA Administrator Sean O'Keefe paid tribute to Columbia's crew, which included six Americans and Israel's first astronaut.
"They dedicated their lives to pushing the scientific challenges for all of us here on earth and they dedicated themselves to that objective and did it with a happy heart, willingly, and with great enthusiasm," he said.
The demise of the space shuttle Columbia immediately brought to mind images of the last shuttle disaster, the explosion shortly after liftoff of the space shuttle Challenger in 1986.
That was 17 years ago, long enough for many to forget that launching a rocket into space still entails a degree of risk.
"Today was a very stark reminder that this is a very risky endeavor, pushing back the frontiers in outer space," said Bill Readdy, a former shuttle commander who now supervises NASA's human space flight program. "And after 113 flights, unfortunately people have a tendency to look at it as something that is more or less routine. Well, I can assure you it is not."
At the White House, it fell to President Bush to try to reassure the nation in the wake of the loss of Columbia, much as then President Ronald Reagan did in the wake of the Challenger disaster 17 years ago.
"Mankind is led into the darkness beyond our world by the inspiration of discovery and the longing to understand," he said. "Our journey into space will go on. In the skies today, we saw destruction and tragedy. Yet, farther than we can see, there is comfort and hope."
Shuttle missions are now on hold while an independent commission investigates the Columbia tragedy.
U.S. officials say the grounding of the three remaining shuttles will not immediately affect the Russian and two Americans currently aboard the international space station.
The space station includes a Russian escape vehicle and a Russian re-supply flight scheduled to launch Sunday should contain enough food and other items that would allow the space station crew to remain aboard until June.