On August 30, 1984, Space Shuttle Discovery launched on its maiden flight, mission STS-41-D, from Kennedy Space Center. The crew of six, commanded by Henry Hartsfield, deployed three communications satellites during the six-day mission. Discovery was the third operational orbiter in NASA's shuttle fleet, following Columbia and Challenger. Over its 27-year service life, Discovery completed 39 missions and spent 365 days in space, more flights than any other orbiter in the program.