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.
When space travel goes wrong â Three Soviet cosmonauts were found dead in their Soyuz 11 spacecraft after an apparently normal landing in June 1971. When space travel goes wrong â Seven crew members aboard the Space Shuttle Challenger were killed in January 1986 when the spacecraft exploded shortly after takeoff.