KENNEDY SPACE CENTER, FLA. -- Gathered in the white room on Launch Pad 39A, alongside space shuttle Discovery, the STS-120 crew pauses for a photo. Clockwise from the bottom are Commander Pamela Melroy, Mission Specialists Scott Parazynski and Stephanie Wilson, Pilot George Zamka, Mission Specialists Paolo Nespoli, Daniel Tani and Doug Wheelock (kneeling). Nespoli represents the European Space Agency. After the mission, Tani will remain aboard the International Space Station and return with the STS-122 crew, targeted to launch Dec. 6. The crew is at NASA's Kennedy Space Center for the pre-launch terminal countdown demonstration test, or TCDT. The TCDT provides astronauts and ground crews an opportunity to participate in various simulated countdown activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Launch of Discovery on mission STS-120 is targeted for Oct. 23 at 11:38 a.m. EDT on a 14-day mission. Photo credit: NASA/Kim Shiflett