OTD…July 15 and STS-127

#OTD in 2007…Discovery launched Harmony as the gateway to future international science laboratories

#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