California-based private company SpaceX announced Thursday that its Dragon spacecraft completed key on-orbit tests as part of a historic attempt to be the first commercial company to send a spacecraft to the International Space Station. Early Thursday morning, Dragon\'s thrusters fired, bringing the vehicle 2.4 kilometers below the station. The vehicle completed two key tests at that distance. Dragon demonstrated its Relative GPS and established a communications link with the station. Astronauts commanded on Dragon\'s strobe light to confirm the link worked. If Dragon continues to operate as planned, it will fly to within about 30 feet (nine meters) of the 100-billion-dollar station on Friday and shut down its maneuvering thrusters so the station crew can snare it with a robotic crane and hook it onto a docking port. So far, the demonstration flight has been near flawless, according to progress reports from U.S. space agency NASA and SpaceX since the capsule blasted off atop the Falcon 9 rocket from Cape Canaveral in Florida on Tuesday. Before Dragon\'s liftoff, flights to the space station have always been a government-only affair. Until their retirement last summer, US space shuttles carried most of the gear and many of the astronauts to the orbiting outpost. Since then, American astronauts have had to rely on Russian capsules for rides. European, Japanese and Russian supply ships have been delivering cargo. NASA is looking to the private sector, in this post-shuttle era, to get American astronauts launching again from US soil. It will be at least four to five years before SpaceX or any other private operator is capable of flying astronauts. Photo/credit NASA