A new commercial U.S. rocket soared into the Virginia sky Sunday, April 21, on a debut flight that paves the way for eventual cargo flights to the International Space Station for NASA.

The third try was the charm for the private Antares rocket, which launched into space from a new pad at NASA's Wallops Flight Facility, its twin engines roaring to life at 5 p.m. EDT (2100 GMT) to carry a mock cargo ship out over the Atlantic Ocean and into orbit. The successful liftoff came after two delays caused by a minor mechanical glitch and bad weather.

Built by the Dulles, Va.- based spaceflight company Orbital Sciences, the Antares rocket is a two-stage booster designed to launch tons of supplies to the International Space Station aboard a new unmanned cargo ship called Cygnus. Orbital has a $1.9 billion contract with NASA to provide at least eight resupply flights to the station using Antares and Cygnus. [See photos of Antares rocket's 1st launch]

"Antares has delivered the A-ONE test mission payload into orbit," an Orbital Sciences commentator said. There were cheers out of Orbital's launch control room at ever successful stage of the launch, with the team breaking out in hugs, high fives and handshakes as the rocket reached orbit.

Orbital had much riding on Sunday's successful liftoff, which marked a critical test flight of a new commercial launch system.

"Antares is our largest investment as a company, and the Cygnus resupply is the largest contract we've ever achieved," said Orbital executive vice president Frank Culbertson, a former astronaut who is the company's general manager for advanced programs.

Antares is the largest rocket ever to launch from NASA's Wallops Flight Facility. It lifted off from the new Pad 0A, which is at Wallops but managed by the Mid-Atlantic Regional Spaceport and overseen by the Virginia Commercial Spaceflight Authority.

The launch was expected to be visible from locations all along the East Coast, from Maine to South Carolina, weather permitting. Orbital even held a viewing event for officials in Washington, D.C., and released several photos advising what the rocket would look like from famous landmarks around the Capitol.  [Launch Video: Antares Soars Into Orbit on Debut Flight]

Orbital initially tried to launch the Antares rocket on Wednesday, April 17, but called off the attempt when a vital data cable separated from the rocket earlier than planned, about 12 minutes before liftoff. The company spent Thursday analyzing the glitch and opted not to try for a Friday launch due to foul weather. Strong winds forced a delay on Saturday, but Mother Nature cooperated for Sunday's launch.

Private space cargo ships

Orbital Sciences is one of two companies with NASA contracts for commercial cargo deliveries to the space station. The other firm is Space Exploration Technologies (SpaceX) of Hawthorne, Calif., which has a $1.6 billion deal for 12 space station cargo missions.

With the retirement of NASA's space shuttle fleet in 2011, the agency is relying on commercial companies like Orbital Sciences and SpaceX to provide the vital resupply services — and, eventually, crew launches — required to keep the space station fully stocked and staffed. Before the commercial program, NASA was dependent on Russian, Japanese and European cargo ships for supplies, and it still temporarily relies on Russian Soyuz vehicles for crewed missions.

"This does represent a new way of doing business for NASA," Alan Lindenmoyer, head of NASA's commercial crew and cargo program at the Johnson Space Center in Houston, told reporters before first launch attempt. 

NASA picked Orbital Sciences as a commercial cargo partner in 2008, awarding the firm $288 million to begin developing the Cygnus spacecraft under the agency's Commercial Orbital Transportation Services program. SpaceX won its first COTS award in 2006.

"This is the culmination of a plan that we've been on for several years," NASA deputy administrator Lori Garver told reporters before the Wednesday launch try. "I am thrilled to have two competitors."

Garver said that at least two companies providing cargo services for NASA is vital since it assures access to space and does not allow one company to have a monopoly on station cargo deliveries.

Antares test flight success

During the test launch, the Antares rocket launched on a southeast trajectory over the Atlantic and took 10 minutes to reach its target orbit 155 miles (250 kilometers) above Earth. The rocket carried an 8,377-pound (3,800 kilograms) dummy payload to mimic the weight of an actual Cygnus spacecraft. The mockup was packed with 70 sensors to record how the Antares rocket launch would affect a Cygnus vehicle.

The dummy module is expected to spend at least two weeks in orbit before burning up in Earth's atmosphere, Orbital officials said.

Antares also carried three coffee cup-size Phonesat satellites - called Alexander, Graham and Bell - into orbit as part of a space technology experiment for NASA's Ames Research Center in California. The tiny 4-inch-wide satellites use commercial smartphones as their main computers. Another small satellite the size of a bread box, called Dove-1, also rode into orbit as part of a commercial agreement for the California-based company Cosmogia. Dove-1 is reportedly an Earth-observation and remote sensing satellite, according to a NOAA remote sensing license document. 

Orbital's Antares rocket is a two-stage booster that stands 131 feet (40 meters) tall and weighs 639,341 pounds (290,000 kilograms) at liftoff.

The first stage is powered by two Aerojet AJ26 liquid-fueled rocket engines originally developed to launch Russia's giant N-1 moon rocket in the 1960s. Today's launch marked their first flight ever from U.S. soil.  The Antares second stage is a solid-fueled motor built by Allliant Techsystems (ATK), the same company that built the twin solid rocket boosters for NASA's space shuttle launches.

With the test flight now complete, Orbital is now looking forward to up to two more launches this year, both of them headed to the International Space Station. That first cargo flight, a demonstration mission, could launch in June, Orbital officials said.

Editor's note: If you snap a great photo of Orbital's Antares rocket launch that you'd like to share for a possible story or image gallery, send photos, comments and your name and location to managing editor Tariq Malik at spacephotos@space.com.

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik and Google+Follow us @Spacedotcom, Facebook and Google+. Original article on SPACE.com.

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