Input (grade 13): January 28 - STS-51-L: Space Shuttle Challenger disintegrates 73 seconds after launch, killing the crew of 7 astronauts, including schoolteacher Christa McAuliffe (see Space Shuttle Challenger disaster).
Output (grade 12): January 28 - Space Shuttle Challenger disintegrates 73 seconds after launch, killing all seven astronauts on board.