Space Shuttle Challenger disaster anniversary
The Challenger exploded 73 seconds into flight at about 11:40 a.m. on Jan. 28, 1986, killing all seven astronauts aboard.
On board was New Hampshire school teacher Christa McAuliffe. She would have been the first teacher in space.
The explosion was caused by a rocket booster failure, which ignited the fuel tank.
The disaster shut down NASA's shuttle program for over two years. Flights resumed on Sept. 29, 1986 with the Shuttle Discovery.