On February 19, 2016 the US "Cygnus” (CRS OA-4) unmanned supply spacecraft was undocked from the International Space Station. The spacecraft, which had been attached to the space station since December 9, 2015 was released by astronauts aboard the station using the orbiting complex's huge robotic arm at 10:40 UTC. It was the 4^th flight of "Cygnus” to the ISS.