The S1 (Starboard One) truss sits in the Kennedy Space Center, Fla., Space Station Processing Facility in June 2002. White thermal blankets on the truss protect the components from temperature extremes in space. Along the top of the truss is the radiator assembly that will rotate and extended in orbit. Space shuttle Atlantis will deliver S1 during mission STS-112. S1 attaches to the right of the S0 (Starboard Zero) truss already aboard the space station. The P1 (Port One) truss is a mirror image of S1 and will be carried aloft by space shuttle Endeavour on mission STS-113. P1 attaches to the left side of the S0 truss. The space station's truss structure will eventually span more than 300 feet and carry power, data and environmental services throughout the orbital outpost. Boeing is NASA's prime contractor for the International Space Station and responsible for design, construction, integration and operation of the station.