Stock Photo - 06/18/1999 __ Workers in the Operations & Checkout Bldg. O&C look over a central component of the International Space Station ISS, the S0 S zero truss. It is undergoing processing in the O&C during which the Canadian Mobile Transporter, power distribution system modules, a heat pipe radiator for cooling, computers, and a pair of rate gyroscopes are being installed. A 44by 15_foot structure weighing 30,800 pounds when fully outfitted and ready for launch, the truss will ultimately extend the length of a football field. Eventually the S0 truss will be attached to the U.S. Lab, Destiny, which is scheduled to be added to the ISS in April 2000. Later, other trusses will be attached to the S0 on_orbit. The S0 truss is scheduled to be launched in the spring of 2001