 Complete the following phrase:  Columbia was the first space-worthy orbiter, and made its inaugural flight in 1981. Challenger, Discovery, and Atlantis followed in 1983, 1984, and 1985 respectively. In 1986, Challenger was destroyed in an accident in 1986 shortly after its 10th launch. Endeavour was built as Challengers successor, and was first launched in 1992. In 2003, Columbia was 