Cygnus departs ISS, prepares for SAFFIRE experiment
After spending a month attached to the International Space Station, Orbital ATK’s OA-5 Cygnus was detached and released by the robotic Canadarm2 in the morning hours of Nov. 21.
The S.S. Alan Poindexter, as the cargo ship is named, was unberthed from the Earth-facing port of the Unity module and moved to about 33 feet (10 meters) below the outpost. A couple hours later, at 8:22 a.m. EST (13:22 GMT), astronaut Shane Kimbrough commanded the Canadarm2 to release the craft. The space station was flying 251 miles (404 kilometers) over the Pacific Ocean just west of Columbia at the time.
“ISS received more than 5,000 pounds of equipment, supplies, and payloads, which put the station in great shape,” Kimbrough radioed from the outpost. “It was an honor to work on this Cygnus flight, especially since it was dedicated to our colleague Alan Poindexter. From the Expedition 50 crew, thank you again to all the people who made this flight such a huge success.”
Cygnus was launched just over a month earlier on Oct. 17 atop Orbital ATK’s upgraded Antares 230 rocket. It rendezvoused with the space station and was berthed about a week later. Since then, the Expedition 50 crew had worked to unload the more than 5,000 pounds (2,267 kilograms) of cargo.
Additionally, the craft was loaded with trash and other unneeded equipment for its eventual re-entry and destruction.
However, that won’t occur for at least a week as the Cygnus still has unfinished business. On board is a follow-up to the SAFFIRE-I experiment, which launched on the last Cygnus back in March 2016.
On this Cygnus is SAFFIRE-II. It will continue the fire burning experiments of SAFFIRE-I, but with nine smaller samples instead of one giant material.
SAFFIRE is the largest in-space flame experiment. As such, it will only be conducted remotely while the spacecraft is at a safe distance away from the crewed space station. Once complete, the data will be downlinked to Earth.
After that, Cygnus will be commanded to deorbit and burn up over the Pacific Ocean.
The next cargo ship to launch to the ISS will be Progress MS-04. It is scheduled to launch out of Baikonur Cosmodrome in Kazakhstan on Dec. 1. A little over a week after that, Japan will launch its Kounotori 6 spacecraft from the Tanegashima Space Center. Liftoff for that will occur on Dec. 9.
Video courtesy of NASA
Derek Richardson has a degree in mass media, with an emphasis in contemporary journalism, from Washburn University in Topeka, Kansas. While at Washburn, he was the managing editor of the student run newspaper, the Washburn Review. He also has a website about human spaceflight called Orbital Velocity.