Endeavour (OV-105) was the final of six Space Shuttles to be built by Rockwell International, and its construction was authorized by the US Congress in 1987. It was produced as a replacement for Challenger, which was lost during in a tragic launch accident in 1986. Endeavour utilized structural spares left over from construction of Discovery and Atlantis, as it was deemed cheaper to build the final Space Shuttle from spare parts rather than produce an entirely new craft. Endeavour took its name from the British ship that Captain James Cook used on his first voyage of discovery in 1768-71. Endeavourís first flight occurred in May 1992, and its final journey to the International Space Station (ISS) took place in May 2011. Its 20-year career encompassed 25 forays into space. The latter half of its series of flights revolved around trips to the ISS. It was scheduled to conduct the final Space Shuttle mission, but this task later fell to Atlantis. Instead, Endeavour performed the penultimate mission before the entire Space Shuttle was retired in 2011. The craft will eventually be exhibited at the California Science Center.