It is now 13 months since an Orbital Sciences Antares rocket exploded just seconds after launch, sending its on-board Cygnus cargo spacecraft crashing back to Earth in a spectacular fireball.
Now, just over a year on, Cygnus is preparing to fly again. With analysis of the Antares failure continuing, it will be launching on top of a United Launch Alliance (ULA) Atlas V rocket this Thursday, December 3.
With Antares grounded, and fellow cargo supplier SpaceX also not flying following their own rocket failure on June 28, this will be the first launch to the ISS from American soil since the SpaceX CRS-6 mission on April 14.
The crew on the space station have not been devoid of supplies, though – several vehicles from Russia and one from Japan have been sent in the meantime. Nevertheless, this return to launch for America is important to keep regular supply missions to the station ongoing.
"This is an exciting time; the Cygnus launch will resume regular U.S.-based cargo missions to the station," said Randy Gordon, launch support project manager for NASA, in a statement. "Atlas V has put satellites in orbit reliably and we are thrilled to be partners both with ULA on the Atlas and with NASA for to fly Cygnus to deliver this important cargo to the space station," added Dan Tani, a former astronaut who is now Orbital ATK's senior director of mission and cargo operations.
Cygnus is seen here ahead of the launch this Thursday. NASA
This version of the Cygnus vehicle is slightly upgraded from its predecessors. Standing just over six meters (20.5 feet) tall, it will be capable of taking 25 percent more cargo to orbit than before, while new lightweight Ultrafex solar arrays will unfurl into a circle in orbit, rather than the heavier rectangular arrays used before.
On board will be a variety of scientific instruments and experiments, including a new life science facility that will support studies of bacteria and microorganisms in orbit, and the first microsatellite that will be deployed from the station.
The spacecraft, named the S.S. Deke Slayton II in honor of the Mercury 7 astronaut of the same name, will fly autonomously to the ISS before it is grabbed by the station’s robotic arm. After three weeks at the ISS, it will be loaded with junk and waste and sent to burn up in Earth’s atmosphere, as it does not have the capability to return to the ground like SpaceX’s Dragon.