KENNEDY SPACE CENTER, FLA. - At Vandenberg Air Force Base in California, the Demonstration of Autonomous Rendezvous Technology (DART) is mated to the belly of the Orbital Sciences Corporation Stargazer L-1011 aircraft. DART was designed and built for NASA by Orbital Sciences as an advanced flight demonstrator to locate and maneuver near an orbiting satellite. The DART spacecraft weighs about 800 pounds and is nearly 6 feet long and 3 feet in diameter. From beneath the belly of the Orbital Sciences L-1011 aircraft, the Pegasus XL vehicle will launch DART into a circular polar orbit of approximately 475 miles. The DART satellite provides a key step in establishing autonomous rendezvous capabilities for the U.S. Space Program. While previous rendezvous and docking efforts have been piloted by astronauts, the unmanned DART satellite will have computers and cameras to perform its rendezvous functions.