(ROUGH CUT ONLY - NO REPORTER NARRATION)br br An unmanned rocket owned by privately held Space Exploration Technologies blasted off from Cape Canaveral Air Force Station on Tuesday (May 22) for a mission designed to be the first commercial flight to the International Space Station.br br The 178-foot (54-meter) tall Falcon 9 rocket lifted off at 3:44 a.m. (0744 GMT) from a refurbished launch pad just south of where NASA launched its now-retired space shuttles.br br The U.S. space agency is counting on companies like Space Exploration Technologies, or SpaceX, to take over flying cargo - and eventually astronauts - to the 100 billion US dollar space station, which orbits about 240 miles (390 km) above Earth.br br Currently, NASA is dependent on Russia to fly crew to the station, at a cost of more than 60 million US dollars per person.br br If its test flight is successful, SpaceX would become the first private company to reach the space station, a microgravity research complex for biological, materials, fluid physics and other science experiments and technology demonstrations.