heart murmur a sound additional to the normal heart sounds, heard on auscultation of the heart. Many murmurs are of no significance (innocent, physiological murmurs), particularly in young children, or due to increased blood flow through the heart during exercise, or in pregnancy.
Columbia Space Shuttle Disaster. On February 1, 2003, the space shuttle Columbia was returning from its 28th mission when, 16 minutes to touchdown, the shuttle incinerated and broke apart over Texas. Communication between the Columbia crew and Mission Control captures the last moments of the flight.
January 28th, 1986 at 11:39am EDT - The Space Shuttle Challenger Explodes on its 10th flight during mission STS-51-L. The explosion occurred 73 seconds after... January 28th, 1986 at 11:39am EDT - The Space Shuttle Challenger Explodes on its 10th flight during mission STS-51-L. The explosion occurred 73 seconds after liftoff and was actually the result of rapid deceleration and not combustion of fuel.