The crew members of mission STS-120 arrive to take part in terminal countdown demonstration test activities.

The crew members of mission STS-120 arrive at NASA's Kennedy Space Center Shuttle Landing Facility aboard T-38 jet aircraft to take part in terminal countdown demonstration test activities. Mission Specialist Scott Parazynski, who will be making his fifth shuttle flight, waves to those on hand to greet him. The terminal countdown demonstration test 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 to the International Space Station. Photo credit: NASA/Kim Shiflett