This was to be the 25th time an American Space Shuttle (from NASA's "Space Transport System") would launch from Cape Canaveral. People were so used to the flights, most folks no longer watched shuttle liftoffs. This flight was different, though. Everyone - including school children - would be watching because Christa McAuliffe was going into space.

But the launch mechanism for America's Supersonic Transport Shuttles had a fundamental design flaw. Roger Boisjoly did his best to warn both his employer, Morton Thiokol, and NASA. But the people to whom he reported wouldn't listen. And the people who made the ultimate decisions at NASA, weren't told. As a result, Challenger and its seven-member crew - including America's first teacher in space - were blown out of the sky 73 seconds after launch on January 28, 1986.

A potential disaster had loomed long before that fateful January day. Although NASA had flown 24 successful shuttle missions before STS 51-L (the official name for the 1/28/86 Challenger mission), other flights had experienced lesser versions of the same problem that caused the Challenger explosion. Trouble is, neither the astronauts nor their families knew about it. But the manufacturer of the shuttle's solid rocket booster (SRB) and solid rocket motor (SRM) knew. So did some of the management officials at NASA.