Liftoff: First U.S. shipment in months flying to space station

Orbital ATK (NYSE:OA), a global leader in aerospace and defense technologies, successfully launched its Cygnus spacecraft today aboard a United Launch Alliance (ULA) Atlas V launch vehicle with approximately 7,700 pounds (3,500 kilograms) of cargo for the crew aboard the International Space Station (ISS), beginning the company’s fourth operational cargo resupply mission for NASA.

“Liftoff, on the shoulders of Atlas”, NASA spokesman Mike Curie said as the unmanned spacecraft blasted off from Cape Canaveral, Florida atop a white Atlas V rocket at 4:44 pm (2144 GMT).

However, launch managers said Sunday’s weather forecast provides only a 40 percent chance of meeting launch requirements.

The rocket holds 7,400 pounds of supplies for the International Space Station.

This Cygnus capsule has been named the SS Deke Slayton II, in honor of the late Mercury (and Apollo-Soyuz) astronaut. (Deke Slayton I was the capsule destroyed previous year.) It’s due to reach the station for grappling and berthing on Wednesday. An Orbital rocket exploded seconds into a mission in October 2014. Orbital ATK bought another company’s rocket, the veteran Atlas V, for this supply mission.

NASA astronaut Scott Kelly on the International Space Station captured this view from orbit as the Cygnus cargo ship launching spaceward on an Atlas V rocket on Sunday, Dec. 6 2015.

Just after 6 p.m., engineers confirmed that the cylindrical spacecraft’s two solar arrays had unfurled like Japanese fans, ensuring they could generate the power needed to complete the mission. SpaceX, the other supplier, suffered a launch failure in June on its eighth trip. Next stop: “@Space_Station”, Orbital ATK tweeted. The vehicle will arrive at the space station on Thursday, and is likely to deliver roughly 4 tons of supplies, like a life sciences facility, Microsoft HoloLens sets, microsatellite launcher and other tools. NASA aims to keep a six-month supply of food aboard and is now down to a four-month cushion.

While redesigning the Antares with different engines, Orbital ATK purchased two Cygnus launches on the Atlas V flown from Cape Canaveral by ULA, a Boeing-Lockheed joint venture. Two private companies contracted for more than $3.5 billion by NASA to replenish the 250-mile-high lab are stuck on Earth with grounded rockets.

If the launch succeeds, the rocket will deliver Cygnus into orbit within 21 minutes, or less than the average time for a pizza delivery.

The resupply services contract between NASA and Orbital ATK requires 10 missions to the ISS that would total 63,272 lbs of cargo.