It was four days late due to a glitch and bad weather, but Orbital Sciences' Antares got off the ground to a flawless test flight ahead of cargo trips for the International Space Station.
The 600,000-pound rocket soared into the sky at 5 pm, burning liquid oxygen and kerosene fuel as it climbed toward orbit, where it released a simulated cargo vessel. The flight paves the way for Antares supply missions to the International Space Station, expected to begin in June or July.