Endeavour rolled out of Boeing's Palmdale, Calif., plant on April 25, 1991. It was the fifth space shuttle to be built, constructed as a replacement for Challenger, which was lost in 1986. Endeavour was largely constructed from structural spare parts and was built in considerably less time than previous orbiters. Endeavour flew the first assembly mission to the ISS, STS-88 in 1998, and the final ISS assembly mission STS-134 in 2011. This image shows Space Shuttle Endeavour (OV-105) being rolled out at the Palmdale, Calif., facility on April 25, 1991. Boeing is the manufacturer of the space shuttle orbiters.