The last song the lost crew of the space shuttle Columbia ever heard was Scotland the Brave by the 51st Highland Brigade. That was the wake-up song beamed up by NASA on the morning the ship was supposed to return to earth. The day before it had been Shalom Lach Eretz Nehederet, for Israeli astronaut Ilan Ramon. Thursday morning it had been John Lennon's Imagine. Scotland the Brave was for mission specialist Laurel Clark, Scottish by extraction.
"Good morning," Mission Control called up to the ship.
"Good morning, Houston," Clark answered. "We're getting ready for our big day up here ... I'm really excited to come back home. Hearing that song reminds me of all the different places down on Earth and all the friends and family that I have all over the world."
She had reason to be excited, particularly since that business of coming home should have been relatively routine--at least by the high-wire standards of space travel. After shimmying out of their sleep restraints, the crew would stow gear and belt themselves into their seats--a process that would take a good six hours. With Columbia turned rump forward, the commander would then fire the main maneuvering engines, slowing the spacecraft and easing it toward the upper wisps of the atmosphere. Once he turned the ship around, he would surf the currents of the steadily thickening air, fishtailing this way and that until, just an hour or so after the deorbit engines were lit, Columbia's tires would make their smoking contact with the Cape Canaveral runway and the shuttle would come to a rolling stop.
That's the way it ought to have happened, at least--and that's the way it did happen on 111 earlier shuttle flights, 27 of them by the venerable Columbia. But only 15 minutes from its planned touchdown, more than 200,000 ft. (61,000 m) over Texas, the 22-year-old ship suddenly and fatally deconstructed itself, taking the lives of its seven crew members with it.
"A space-shuttle contingency has been declared," the voice of Mission Control intoned in the arid argot of the space agency. It was an echo of the understated announcement 17 years ago, when the shuttle Challenger consumed itself in an awful fireball, and the stunned NASA narrator was left to declare, "Obviously a major malfunction."
Then, as now, the question is the same: Why?
A full inquest into the death of the shuttle Columbia--the second of the star-crossed fleet of five to be lost in flight--will take months if not years. Investigators will be looking at everything from a loss of insulating tiles to an explosion in the fuel tanks to a structural failure in the bones of the ship itself, as Columbia juked and torqued its way through the atmosphere. In a flying machine with more than 2.5 million parts, even a 99.9% reliability level would still leave 2,500 things to go wrong.