OTD…Sept. 20 and Endeavour retirement

#OTD in 2001…Atlantis launched the Quest airlock module to the International Space Station

Neil Armstrong, Buzz Aldrin and Michael Collins launched today in 1969 aboard Apollo 11 for one of the defining moments of the 20th century — man’s first landing on the moon.

#OTD in 2009, shuttle Discovery delivers power payload to space station.