OTD…April 29 and STS-51B

#OTD…In 2009, the final Hubble Space Telescope servicing mission launched

#OTD…Launch of a 1993 environmental mission on Discovery and Atlantis’ ISS flight in 2002

#OTD in 2007…NASA’s Dawn probe launched to explore the uncharted worlds of Vesta and Ceres in the heart of the asteroid belt.