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.
Jan. 28, 1986: Challenger disaster plays out on live TV. The excitement lasted only 73 seconds. On January 28, 1986, 1 minute and 13 seconds after liftoff, space shuttle Challenger exploded as thousands watched the launch in person and on television. All seven astronauts on board were killed. It became one of the most iconic live breaking news events in television history.