Editorial use only NASA astronaut and teacher Christa McAuliffe (1948-1986) exiting a T-38 jet at Ellington Field near the Johnson Space Center, Texas, USA during training. McAuliffe was one of ten finalists in the NASA Teacher in Space Project. She was selected as a payload specialist on the NASA shuttle Challenger mission 51-L, which exploded seventy three seconds after lift off on the 28th January 1986. All seven crew members were killed. It is thought that the accident was caused by a failure of an 0-ring in a seal on the right hand solid rocket booster, with consequent ignition of the leaking fuel.