A SpaceX Dragon capsule headed back to Earth on Wednesday, filled with more than 1,678 kilograms (3,700 pounds) of experiment results and cargo from the International Space Station, a NASA TV broadcast showed.
It was the first return load from the station in a year, following a SpaceX launch accident in June 2015 that destroyed another Dragon capsule.
The company's Dragon capsules are currently the only ships that can return cargo from the station, a $100 billion research laboratory that flies about 250 miles (400 km) above Earth.
SpaceX resumed Dragon flights to the station last month.
On Wednesday, ground controllers at NASA's Johnson Space Center in Houston used the station's robot arm to pluck the unmanned capsule from its berthing port at 7:02 a.m. and position it for release into space.
British astronaut Timothy Peake, working from inside the space station's cupola module, then commanded the crane to free its grip at 9:19 a.m. as the station sailed over Australia so Dragon could begin its ride back to Earth.
"Dragon spacecraft has served us well. It's good to see it departing full of science and we wish it a safe recovery back on planet Earth," Peake radioed to Mission Control in Houston.
Splashdown in the Pacific Ocean off the coast of California is expected at 2:55 p.m.
Dragon's returning cargo includes blood and urine samples from the one-year mission of former U.S. astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko. The men returned to Earth March 1.