Japan's cargo spacecraft Kounotori is returning to Earth with a recovery capsule from the International Space Station.
The Kounotori 7 was launched in September and delivered food and other supplies to the space station, along with a capsule for bringing back supplies.
American and European astronauts, who crystallized protein for medical research in zero gravity, carefully placed the matter in the capsule and fixed it to the tip of Kounotori. The craft was detached from the space station at 16:50 Wednesday UTC as scheduled.
The capsule developed by Japan's space agency JAXA is shaped like a cone, with a bottom diameter of more than 80 centimeters.
It is designed to withstand temperatures of about 2,000 degrees Celsius.
The capsule is scheduled to be detached from Kounotori and reenter the atmosphere on Sunday Japan time. It will land in the Pacific Ocean near the Ogasawara Islands, where it will be recovered by ship.
The Kounotori itself is designed to burn up in the atmosphere.
Currently, only the US and Russia have recovery capsule technology. If Japan succeeds, it would pave the way for the country's manned space exploration.