The next U.S. cargo delivery to the International Space Station is steadily progressing toward launch. An Orbital ATK Cygnus spacecraft is at NASA's Kennedy Space Center in Florida undergoing a final round of prelaunch preparations for its December liftoff aboard a United Launch Alliance Atlas V rocket. This will be Orbital ATK's fourth commercial resupply flight to the station and will carry more than 7,000 pounds of supplies, equipment and research to keep the station stocked and capable of serving as a platform for studies off the Earth, for the Earth.

The Atlas first-stage booster arrived Nov. 8 aboard the United Launch Alliance barge, the Delta Mariner. The uncrewed Cygnus spacecraft comprises a pressurized cargo module and an attached service module housing the onboard propulsion system and twin power-producing solar arrays.

Processing began with the Aug. 10 arrival of the Cygnus pressurized module, followed by the service module about two months later. Both were delivered by flatbed truck to Kennedy's Space Station Processing Facility (SSPF). The pressurized module was loaded with cargo Oct. 19 and 20, rotated to vertical and mated to the service module on Oct. 22, clearing the way for the journey to the Payload Hazardous Servicing Facility.

The PHSF has played host to a variety of planetary probes, as well as the Hubble Space Telescope and Orion spacecraft - but Cygnus marks another first. "This is the first time a spacecraft bound for ISS has processed within this facility," said Launch Site Integration Manager Mark Shugg.

The spacecraft's arrival in the PHSF high bay kicked off a series of processing steps beginning with the loading of the spacecraft's propellants, hydrazine and an oxidizer. In the coming days, it will be rotated into the horizontal position, allowing Orbital ATK engineers and technicians to load late-stow cargo items into the pressurized module. Finally, Cygnus will be returned to vertical and sealed within the Atlas V payload fairing, an activity slated for Nov. 17.

At that point, its next stop is Space Launch Complex 41.

"This has been an extremely accelerated process, to get from an initial starting point early this year and be at the point of accepting them into our facility. We accomplished in a few months what we would normally do in two years of preparation for our typical Launch Services Program spacecraft customers," Shugg said.

"We are very happy to extend the use of our facility to this cause. There is no other facility on [Kennedy Space Center] property that has the capability to perform the hazardous processing that is required for this mission," he added.

This mission marks the first flight of the Cygnus since Oct. 28, 2014, when the company's Antares rocket suffered a catastrophic anomaly resulting in the loss of the spacecraft and its cargo shortly after liftoff from Pad 0A of the Mid-Atlantic Regional Spaceport at NASA's Wallops Flight Facility in Virginia.

"With a new customer like Orbital ATK/Cygnus, there is a learning curve from both sides as we develop a working relationship. Working on such a tight schedule has caused the teams to immerse themselves in each other's culture and develop that relationship quickly," Shugg said.

Kennedy teams were flexible and responsive as Orbital ATK adapted to the condensed timeline, according to ISS Launch Support Project Manager Randy Gordon.

"They had to move their spacecraft, equipment, people and overall operations to this new location in an extremely short time," Gordon explained.

"It was good having them in the SSPF," he added. "They have a lean workforce, but they worked hard and stayed on schedule."

While the Cygnus is readied for flight, the Atlas V rocket is coming together as well. The vehicle's Centaur upper stage was trucked to the Horizontal Integration Facility at Cape Canaveral Air Force Station on Oct. 27.

The Atlas booster and Centaur will be joined together on the launch pad in time for the arrival of the payload fairing on Nov. 20 - leaving Cygnus poised for liftoff on a new voyage to deliver eagerly awaited supplies and research to the orbiting laboratory.