The seven members of the crew (commander Rick Husband, pilot Willie McCool and mission specialists Kalpana Chawla, Laurel Clark, Mike Anderson, David Brown and Israeli payload specialist Ilan Ramon) were coming to the end of a 16 day mission of scientific experimentation, the first shuttle mission in two years that did not visit the International Space Station or Hubble Space Telescope.
As Columbia was making final preparations for landing, their families were journeying to Kennedy Space Center to watch their loved ones’ homecoming. Columbia and her crew were scheduled to land at Space Center at 9:16 a.m. There was much excitement in both places. Meanwhile, throughout the country and around the world, not only were most people ignorant of the identities of the astronauts, many were unaware there was even a shuttle mission taking place. All of this would change very soon.
Shortly before 9:00AM EST, Mission Control spotted a sensor problem. There was a loss of data from the left wing temperature sensors. This was followed by a data loss from tire pressure indicators on the left main landing gear. Although this was a problem, it could have simply been a communication glitch. There were procedures in place to deal with it.
Mission Control contacted the shuttle, "Columbia, Houston, we see your tire pressure messages and we did not copy your last."
They received a reply from Columbia's commander, Rick Husband, "Roger, uh, buh ..."
There was nothing more for several seconds, then, they received only static.
The shuttle was traveling at 12,500 mph, 18 times the speed of sound, 39 miles above the Earth, when people in Texas, Arkansas, and Louisiana heard unusual sounds coming from the sky. Many who were watching to see the shuttle pass overhead reported seeing debris separating from the vehicle. This was a clear indication that something was wrong. Minutes later, NASA announced that a Space Shuttle Contingency had been declared.
By nightfall, with debris spread across a large portion of Texas and into Louisiana, search was put on hold until morning. The search for debris and bodies will be over in a few days, but the search for answers will take much longer.