STS-126 Mission Specialists Sandra Magnus Donald Pettit and Heidemarie Stefanyshyn-Piper pause for a photo.

During suit-up in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-126 Mission Specialists Sandra Magnus, Donald Pettit and Heidemarie Stefanyshyn-Piper pause for a photo. The crew members are having their launch-and-entry suits fit-checked prior to heading for Launch Pad 39A. The crew will take part in a simulated launch countdown at the pad. The crew is at Kennedy to take part in the Terminal Countdown Demonstration Test, which includes equipment familiarization, emergency exit training and the simulated countdown. On the STS-126 mission, space shuttle Endeavour's crew will deliver equipment and supplies to the International Space Station in preparation for expansion from a three- to six-person resident crew aboard the complex. The mission also will include four spacewalks to service the station’s Solar Alpha Rotary Joints. Endeavour is targeted to launch Nov. 14. Photo credit: NASA/Kim Shiflett