OTD…Aug. 27 and STS-51I

#OTD in 2002…Atlantis launched the outward expansion of the space station’s truss backbone

#OTD in 1994…Discovery launched to develop new techniques for monitoring Earth’s environment from space…and in 2006…Construction of the space station resumed as Atlantis delivered a power-generating truss

#OTD in 1991…The launch of Columbia on Spacelab Life Sciences 1 mission