P1 Truss in Huntsville, Ala.

Boeing technicians in Huntsville, Ala., lower the P1 (Port One) truss into a work stand. Space shuttle Endeavour will deliver P1 during mission STS-113. P1 attaches to the left of the S0 (Starboard Zero) truss already aboard the space station. The P1 truss is a mirror image of S1 (Starboard One) to be carried aloft by space shuttle Atlantis on mission STS-112. S1 attaches to the right 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.