The STS-116 crew members show their eagerness for launch as they exit the Operations and Checkout Building.

The STS-116 crew members show their eagerness for launch as they exit the Operations and Checkout Building. From the back are Mission Specialists Robert Curbeam, Sunita Williams, Christer Fuglesang and Nicholas Patrick; Pilot William Oefelein; Mission Specialist Joan Higginbotham; and Commander Mark Polansky. Fuglesang represents the European Space Agency. Williams will replace Expedition 14 crew member Thomas Reiter, who will return to Earth aboard Discovery in her place. This is Discovery's 33rd mission and the first night launch since 2002. The 20th shuttle mission to the International Space Station, STS-116 carries another truss segment, P5. It will serve as a spacer, mated to the P4 truss that was attached in September. After installing the P5, the crew will reconfigure and redistribute the power generated by two pairs of U.S. solar arrays. Landing is expected Dec. 19 at KSC. Photo courtesy of Nikon/Scott Andrews