Timeline of re-entry as told by Milt Heflin, NASA chief flight director, during a televised press conference. (all times EST)
8:15 a.m. Space shuttle Columbia fires its rockets and makes its way toward touchdown.
8:53 a.m. Mission control loses data from four temperature sensors located on the inboard and outboard hydraulic systems on the left side of the craft.
8:56 a.m. A temperature and pressure increase is detected in the left tire wheel-well.
8:58 a.m. Mission control loses data from three sensors located on the left wing.
8:59 a.m. Mission control loses left side tire temperature and pressure data, and receives final communication from crew.
Approximately 9 a.m.
Communication with the vehicle is lost. Last recorded shuttle altitude was 207,135 feet, traveling about Mach 18.3 (18 times the speed of sound). NASA makes attempts to contact Columbia.
Reports of a loud noise and streaming balls of light in the sky come in from Texas and Louisiana.
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