The SpaceX Crew Dragon Endeavour capsule splashed down off the coast of Florida late Monday carrying four astronauts who had spent the last six months on the International Space Station.
The "Crew-2" astronauts conducted hundreds of experiments and helped upgrade the station's solar panels.
The capsule, dubbed "Endeavour", and undocked from the ISS at 2:05 pm (19:05 GMT Monday), NASA announced.
It landed in the Gulf of Mexico at 10:33 pm US Eastern Time (03:33 GMT Tuesday), marking the end of the "Crew-2" mission.
A boat dubbed the "Dragon's Nest," then lifted the capsule out of the water, for the astronauts to be brought back to land via helicopter.
"The Crew-2 astronauts and Dragon spent 199 days in orbit, the first US spacecraft to reach that milestone," SpaceX tweeted.