Center Truss

The Center Truss, which has the cryptic official name of "ITS S0", is the central section of the truss structure of the Space Station.  The Center Truss links the pressurized modules where the crew live and work with the power and thermal systems located further out.  Wires for electrical power and communications, and pipes with ammonia for the thermal control system, go along the truss.  Mounted on the truss are two power conversion units, which adjust the voltage and current from the solar arrays to the voltage and current that the modules will use, and antennas to receive radio signals from the Global Positioning System, which locate the station during Earth observation experiments and for rendezvous of supply vehicles and new modules.  Also found here as is the Mobile Transporter, a moving base for the Space Station's Robotic Arm.  The Mobile Transporter will slide along the truss segments, and will help to position the modules during later assembly flights. Other items on the Center Truss include an external video switch, plasma contactors and a portable work platform. The Center Truss is 44 feet (13.5 meters) long and 15 feet (4.62 meters) in diameter.  The whole unit will weigh 33 400 pounds (15 182 kilograms) at launch.       

