Orbital had hoped to begin its rocket launches under the commercial resupply program in 2011, but faced a series of delays. That included a delay in the completion of its launch pad at NASA's Wallops Flight Facility on the Virginia coast. That pad was built specifically for Orbital and is owned by the Virginia Commercial Space Flight Authority. The pad wasn't delivered to the company until October.
Following Sunday's launch, Culbertson declined to get into specifics about what caused all the delays over the past two years.
"Rockets are hard. Space flight is difficult and getting off the ground is a real challenge for whatever team is trying to do it," he said. "The way I look it is we are on a new schedule now and we're on schedule."
NASA, meanwhile, is looking to private companies to start sending astronauts to the space station in coming years. Orbital is not in the running for that work though SpaceX, based in Hawthorne, Calif., is working to modify its Dragon capsules to transport astronauts. A handful of U.S. companies are competing for that assignment. Until then, U.S. astronauts are hitching rides to the International Space Station on Russian Soyuz rockets.
"With NASA focusing on the challenging and exciting task of sending humans deeper into space than ever before, private companies will be crucial in taking the baton for American cargo and crew launches into low-Earth orbit," John Holdren, assistant to the president for science and technology, said in a blog post on the White House's website congratulating Orbital.
Sunday's launch drew scores of onlookers to Wallops Island's visitor center on the mainland several miles away, where people set up blankets and camp chairs near marshland to view the launch. Road signs also directed rocket launch fans to nearby Assateague Island, where the rocket launch could be seen from the beach.
For Mike Horocofsky of Rock Hall, Md., it was his third time making the drive down to the Virginia facility in hopes of seeing Antares lift off.
"I'd rather be doing this than anything else. It's just something I've enjoyed since I was a boy," Horocofsky said several hours before the launch, while setting up chairs for himself and his wife.
Brock Vergakis can be reached at www.twitter.com/BrockVergakis