KENNEDY SPACE CENTER, FLA. - The STS-115 crew learn about use of the bunker in the event of an emergency at the launch pad. Seen in the photo are, from left, Commander Brent Jett, Mission Specialists Daniel Burbank and Steven MacLean, Pilot Chris Ferguson and Mission Specialist Joseph Tanner. Not pictured is Mission Specialist Heidemarie Stefanyshyn-Piper. The mission crew is at KSC for Terminal Countdown Demonstration Test (TCDT) activities that are preparation for launch on Space Shuttle Atlantis, scheduled to take place in a window that opens Aug. 27. During their 11-day mission to the International Space Station, the STS-115 crew will continue construction of the station and attach the payload elements, the Port 3/4 truss segment with its two large solar arrays. Photo credit: NASA/Cory Huston