In October 2000 he was launched from the Baikonur Cosmodrome to become commander of the first resident crew of the International Space Station. He returned in March 2001 aboard the space shuttle Discovery. Shepherd had previously flown on three space shuttle missions as a mission specialist, including the Discovery flight in October 1990 that deployed the Ulysses probe. He logged more than 159 hours in space. He was selected as an astronaut in 1984 and has since left NASA.