Original: 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 ) .
Simplified: January 24 -- Voyager 2 space probe makes first encounter with Uranus January 28 -- Space Shuttle Challenger disintegrates 73 seconds after launch , killing all seven astronauts on board .