Stock Photo - After suiting up, the STS-126 crewmembers exit the Operations and Checkout Building to board the Astrovan, which will take them to launch pad 39A for the launch of Space Shuttle Endeavour on the STS-126 mission. On the right (front to back) are astronauts Chris Ferguson, commander; Steve Bowen and Heidemarie Stefanyshyn-Piper, both mission specialists. On the left (front to back) are astronauts Eric Boe, pilot; Donald Pettit, Shane Kimbrough and Sandra Magnus, all mission specialists. Magnus will join Expedition 18 in progress to serve as a flight engineer aboard the International Space Station. The mission will feature four spacewalks and work that will prepare the space station to house six crew members for long-duration missions.