December 13

1962 – NASA launches "Relay 1", the first active repeater communications satellite in Earth orbit.
1972 – During the Apollo 17 mission, astronauts Eugene Cernan and Harrison Schmitt begin the third and final moonwalk. They are the last humans to walk on the moon during the 20th Century.

2411 – Space Station Sierra 18, SS-18 is attacked by an alien force of unknown origin and is ultimately destroyed.