WALLOPS ISLAND, Va. -- A privately-owned spaceship built by Orbital Sciences Corp. made an Earth-rattling trip into orbit from Virginia on Wednesday, starting a four-day chase of the International Space Station to close out a nearly $700 million NASA program to foster a fleet of commercial spaceships to replace capabilities lost with the space shuttle's retirement.

The Antares rocket blasted off at 10:58 a.m. EDT (1458 GMT) from launch pad 0A at the Mid-Atlantic Regional Spaceport at Wallops Flight Facility. Credit: NASA/Bill Ingalls

The unmanned Cygnus spacecraft, fitted with an Italian-built pressurized cargo carrier, blasted off at 10:58 a.m. EDT (1458 GMT) aboard an Antares rocket from the Mid-Atlantic Regional Spaceport at Wallops Island, Va.

The Antares rocket, emitting a tongue of orange exhaust and a crackling roar, gracefully soared above its launch pad and pitched over to fly southeast from NASA's Wallops Flight Facility, leaving a twisting trail of smoke hanging in the morning sun as the 13-story rocket sped into space.

The launcher's AJ26 engines, leftovers from Russia's ill-fated moon program of the 1960s, accelerated the Antares rocket high into the stratosphere before consuming its supply of kerosene and liquid oxygen propellants.

The first stage gave way to a Castor 30 solid-fueled motor built by ATK to inject the Cygnus spacecraft into orbit, then deployed the automated spaceship about 10 minutes after liftoff.

A few minutes later, the Cygnus extended two solar array wings built by Dutch Space in the Netherlands and pressurized its propulsion system for four days of engine burns on a shakedown cruise to the International Space Station.

"This was hard," said Frank Culbertson, vice president of advanced programs at Orbital Sciences. "It's difficult to get a rocket off the launch pad. There are a lot of things that have to come together no matter how many times you do it."

The launch replicated a feat Orbital Sciences accomplished in April, when it put the Antares through a test launch without a functioning payload. NASA and Orbital agreed to launch the Antares demo mission as a risk-reduction exercise.

The Antares rocket blasted off at 10:58 a.m. EDT (1458 GMT) from launch pad 0A at the Mid-Atlantic Regional Spaceport at Wallops Flight Facility. Credit: Stephen Clark/Spaceflight Now

The Cygnus spacecraft's next steps break into uncharted territory for Orbital Sciences, a firm with a vaunted history of rocket flights and satellite production, but with little experience in the day-to-day world of human spaceflight.

"This was just step one of the hard part," Culbertson said. "Step two is coming up as we begin the rendezvous and approach the space station."

The Cygnus test flight, operated by Orbital Sciences with objectives mandated by NASA, is the first of nine Orbital Sciences missions to the space station. The next eight sorties - the first is scheduled for December - are under a $1.9 billion Commercial Resupply Services contract between Orbital and NASA.

The ongoing demo mission is the last step in a Commercial Orbital Transportation Services agreement signed between Orbital Sciences and the space agency in February 2008. The pact set up a public-private partnership in which NASA is funneling $288 million to Orbital to help fund the development of the Cygnus and Antares vehicles.

Orbital Sciences says it put even more of its own capital into the programs. In April, Culbertson said design and development of the Cygnus cargo craft cost about $300 million, and the Antares launcher cost a little more, declining to give a specific figure.

Orbital was also a minority investor in the approximately $140 million Antares launch pad and integration hangar at Wallops Island.

Seeing a dearth of U.S. spacecraft capable of resupplying the space station after the space shuttle's retirement, NASA cinched agreements with Orbital Sciences and SpaceX to partially finance new commercial spacecraft and launchers to restore domestic access to the complex for cargo, reducing U.S. reliance on international spaceships.

Artist's concept of the Cygnus spacecraft. Credit: Orbital Sciences Corp.

NASA signed a deal with SpaceX in August 2006 and reached an agreement with Orbital in 2008. California-based SpaceX, founded and led by Internet and technology magnate Elon Musk, completed its COTS demonstration flight to the space station in May 2012. SpaceX has flown twice more to the space station, beginning work under a 12-mission, $1.6 billion resupply contract similar to Orbital's.

Orbital's full-up test flight comes more than a year after SpaceX's end-to-end demo mission, but Orbital officials are quick to point out SpaceX had an 18-month head start.

Ten demonstrations of the Cygnus vehicle's engines, computers and navigation systems are planned before the spacecraft's arrival at the space station Sunday.

Before NASA permits the resupply ship to approach the space station, engineers must prove the Cygnus can accurately maneuver, conduct an emergency abort, and use its GPS and laser navigation systems.

"We agreed to an end-to-end demonstration of their system," said Alan Lindenmoyer, manager of NASA's COTS program. "Orbital is responsible for the entire mission from receiving our cargo from NASA, launching, delivering it on orbit, and then safely disposing of it with the re-entry of the vehicle."

The Cygnus will advance toward the space station from below, flying up from underneath and pausing at preset points before halting about 30 feet below the complex while European Space Agency astronaut Luca Parmitano extends the outpost's robot arm to snag the free-floating spacecraft and place it on a berthing port for a month-long stay.

The spacecraft carries 1,543 pounds of food, office supplies, spare parts and student experiments, and astronauts will unpack that gear and replace it with trash for the Cygnus' departure and plunge back to Earth.

Cygnus carries supplies inside a 10-foot-diameter pressurized cargo module built by Thales Alenia Space in Italy, which also manufactured logistics modules used by the space shuttle and the European Space Agency's ATV resupply craft.

Similar to European, Japanese and Russian supply ships - but unlike the returnable SpaceX Dragon spacecraft - the Cygnus will fall back into the atmosphere over the South Pacific Ocean and burn up during re-entry on Oct. 24.