STS115-S-007 (9 Sept. 2006) --- After suiting up, the STS-115 crewmembers exit the Operations and Checkout Building to board the Astrovan, which will take them to launch pad 39B at Kennedy Space Center. On the right (front to back) are astronauts Brent W. Jett, Jr., commander; Daniel C. Burbank and Joseph R. Tanner, both mission specialists. On the left (front to back) are astronauts Christopher J. Ferguson, pilot; Steven G. MacLean representing the Canadian Space Agency and Heidemarie M. Stefanyshyn-Piper, both mission specialists. During the STS-115 mission, Atlantis' astronauts will deliver and install the 17.5-ton, bus-sized P3/P4 integrated truss segment on the station. The girder-like truss includes a set of giant solar arrays, batteries and associated electronics and will provide one-fourth of the total power-generation capability for the completed station.