Driven by Mission Specialist Daniel Tani moves through the underbrush near Launch Pad 39A.

Driven by Mission Specialist Daniel Tani, the M-113 armored personnel carrier moves through the underbrush near Launch Pad 39A. The M-113 is part of emergency exit procedures from Launch Pad 39A. Also in front is the trainer. In the rear are Mission Specialists Doug Wheelock, Scott Parazynski and Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett