New commercial rocket reaches orbit
Sen—Orbital Sciences Corporation has become the second commercial space company to send a rocket into orbit with the successful maiden flight of its Antares launcher.
Orbital's rocket, designed to launch a cargo supply ship and other hardware into orbit, lifted off at 9pm GMT on April 21 from the Mid-Atlantic Regional Spaceport (MARS) Pad 0A at NASA's Wallops Flight Facility in Virginia, U.S.A. The rocket carried the equivalent mass of a spacecraft into orbit.
The test flight had originally been scheduled for April 17 but had to be scrubbed just 12 minutes before lift off after a premature separation of a launch pad umbilical connection to the upper stage of Antares. Adjustments were made to the connection for the re-scheduled launch.
NASA's boss Charles Bolden, commenting on the successful launch, said: "Today's successful test marks another significant milestone in NASA's plan to rely on American companies to launch supplies and astronauts to the International Space Station, bringing this important work back to the United States where it belongs. Congratulations to Orbital Sciences and the NASA team that worked alongside them for the picture-perfect launch of the Antares rocket. In addition to providing further evidence that our strategic space exploration plan is moving forward, this test also inaugurates America's newest spaceport capable of launching to the space station, opening up additional opportunities for commercial and government users."
Orbital is one of two companies selected by NASA to transport cargo to the space station. The test flight, designated the Antares A-One mission, is the first of two missions set for this year under NASA's Commercial Orbital Transportation Services (COTS) Program. The next mission, scheduled for mid 2013, will see Antares lift Orbital's Cygnus cargo freighter into orbit. Cygnus will then aim to dock with the International Space Station.
The other company chosen to transport cargo, SpaceX, was the first private company to send a rocket into orbit and return it safely to Earth in June 2010. SpaceX has so far completed two supply missions to the orbiting outpost.
NASA awarded Orbital a Commercial Resupply Service (CRS) contract in 2008 for eight cargo resupply missions to the ISS. However, before it can begin fulfilment of its CRS contract the American space company must pass the development and demonstration phase of COTS.
To deliver cargo to the space station, Orbital has been busy building its new Antares and its Cygnus cargo ship. Antares did not carry an operational Cygnus spacecraft on its inaugural flight, but it will on its second flight.
If the demonstration milestones are passed and NASA sign off on Orbital's readiness, the spaceship maker will be cleared to begin delivering supplies to the space station under its CRS contract. Orbital anticipates making its first cargo supply in the third quarter of 2013, though the company points out that the schedule needs to be co-ordinated with NASA and is subject to successful demonstration flights.
The Antares launch vehicle can carry nearly 6 tonnes to low-Earth orbit, while the Cygnus spacecraft will be capable of delivering 2.7 tonnes of pressurized cargo to the space station. Like Europe's Automated Transfer Vehicle (ATV), Japan's HTV and Russia's Progress supply ships, the Cygnus spacecraft will burn up on re-entry. SpaceX's Dragon will remain the only cargo freighter currently able to return goods to Earth.
The demonstration phase of COTS is something SpaceX had to go through. SpaceX was selected under NASA's COTS Program in 2006, whilst Orbital was chosen two years later after another company originally selected alongside SpaceX, Rocketplane-Kistler (RpK), failed to complete financial and technical milestones.
Antares is a two stage vehicle with the launcher's design accommodating an optional third stage. In developing the rocket Orbital has drawn from its engineering experience and launch technologies that have been utilised successfully on its others launchers, Pegasus, Taurus and Minotaur.
NASA's COTS program is part of its strategy of using private companies to deliver cargo and astronauts to low-Earth orbit, in particular the International Space Station.