The unmannedAntares rocket carrying the unmanned Cygnus spacecraft exploded moments after takeoff aboveNASA'sWallops Flight Facility in Wallops Island, Virginia, Tuesday evening. NASA and Orbital Sciences are still trying to assess the damage and understand the cause of the failure.

Screenshot shows explosion in Virginia Tuesday.

(NASA-TV)

The launch was scheduled for 6:22 p.m. ET and aired on a live stream of NASA-TV. The video shows debris falling to the ground.

The company said everyone at the site had been accounted for, and the damage appeared to be limited to the facilities.The Associated Press reports this is the first catastrophic launch in NASA's commercial spaceflight effort.

Flames could be seen shooting into the sky as the sun set. There was no hint of any trouble until the rocket exploded.

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Orbital Sciences' Executive Vice President Frank Culbertson said something began to go wrong about 10 to 12 seconds into the flight. Within 20 seconds it was all over when what was left of the rocket came crashing down. He said he believes the range-safety staff sent a destruct signal before it hit the ground.

"It is far too early to know the details of what happened," Culbertson said in a news release."We will conduct a thorough investigation immediately to determine the cause of this failure and what steps can be taken to avoid a repeat of this incident. As soon as we understand the cause, we will begin the necessary work to return to flight." As such, Orbital is holding a call today at 1 p.m. ET to discuss the launch failure.

"We'll get things back on track," Culbertson said. "We've all seen this happen in our business before, and we've all seen the teams recover from this, and we will do the same."

The weather itself was considered ideal for launch. NASA even called the 66-degree temperature, light winds and 10-mile visibility "100 percent favorable conditions."The agency tweeted a photo (below) of the rocket just minutes before the explosion.

The unmanned spacecraft was carrying 5,000 pounds of supplies to the International Space Station, including books, flight crew equipment, hardware and computer resources.NASA is paying billions of dollars to Orbital Sciences and the SpaceX company to make station deliveries, and it's counting on SpaceX and Boeing to start flying U.S. astronauts to the orbiting lab as early as 2017.

The six people living on the space stationdid not need anything on the lost flight urgently,William Gerstenmaier, Associate Administrator of NASA’s Human Exploration and Operations Directorate, said in a statement. "We will continue to move forward toward the next attempt once we fully understand today's mishap. The crew of the International Space Station is in no danger of running out of food or other critical supplies."

This would have been the Cygnus spacecraft's third official cargo mission to the ISSunder a $1.9 billion contract, according to NASA.

The National Weather Service office in Blacksburg, Virginia, picked up what they called "hot pixels" on the radar in the minutes after the explosion.

The launch was originally scheduled for Monday, but was moved when a boat wandered into the hazard area.

The Wallops flight facility is small compared to major NASA centers such as those in Florida, California and Texas. Those who work at Wallops Island joke that even people living on Virginia's Eastern Shore are surprised to learn about rocket launches there.

Denise Bowden, a spokeswoman for the Chincoteague Volunteer Fire Company, said it looked like a normal launch at first Tuesday. The launch pad on the island is visible from the town about four miles away."When it started off, it looked beautiful. A friend of mine was standing behind me—he works civil service over there with NASA—and he goes, 'Uh, oh.' To me it looked normal, but he knew something was wrong right away. He said, 'It's bad,' and then it just went boom. And then, the explosions followed."

NASA and Orbital are advising people not to touch any debris that might have washed ashore or come down on their property. "Public safety is our No. 1 priority," NASA wrote on its update page. "If people find debris in the vicinity of the launch, please stay away and call the Incident Response Team at 757-824-1295."