Orbital Sciences Antares rocket successfully launched on its maiden voyage at 5 pm EDT (21:00 UTC) on Sunday, April 21 from the Mid-Atlantic Regional Spaceport at NASA's Wallops Flight Facility in Virginia. The test flight is serving as the precursor for a demonstration flight of its Cygnus resupply ship to the International Space Station later this year. About 10 minutes after launch, it placed a mass simulator payload to orbit designed to mimic the Cygnus spacecraft's weight and characteristics. It is in orbit at 250 km (155 miles) in altitude and moving at27,350 km/hr (17,000 mph).