Tonight... Get on On the Record with Greta!

The seven crew members -- six Americans and the first Israeli to go into space -- were just 16 minutes from landing at Cape Canaveral, Fla., when the shuttle broke up at 203,000 feet. The astronauts had been orbiting the Earth for 16 days.

"Columbia is lost. There are no survivors," President Bush said in a televised address from the Cabinet Room. He said the day had brought "terrible news" and "great sadness" to the country, and that "our entire nation grieves."

Bush praised the Columbia crew for their courage and daring in an age when space travel seems so routine, but is anything but.

"These men and women assumed great risk in the service to all humanity," Bush said. "The astronauts knew the dangers and they faced them willingly."

Still, he said, "our journey into space will go on."

What happened? Greta asks the experts what could have caused the catastrophic failure of Columbia.

We've got a great show for you this evening... Get On the Record with Greta Van Susteren at 10 p.m. ET only on the FOX News Channel!

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