OTD…April 12 and STS-1 and 51D

#OTD in 1985…Atlantis launched on her maiden voyage as a new orbiter joined the shuttle fleet

The final manned Mercury mission was launched atop an Atlas rocket on this day in 1963 with Gordon Cooper aboard Faith 7 for a 34-hour, 22-orbit flight.

#OTD in 1994…Columbia launched on a Spacelab microgravity flight