NASA's gumdrop-shaped Orion capsule, dubbed Integrity, parachuted gently into calm seas off the Southern California coast shortly after 5.07pm US Pacific Time on Friday, concluding a mission that four days prior took the astronauts 405,555km away from Earth, deeper into space than anyone had flown before.
The Artemis II flight, travelling a total of 1,117,515km in two Earth orbits and a climactic lunar flyby, was the debut crewed test flight in a series of Artemis missions that aim to return astronauts to the lunar surface starting in 2028.
The splashdown, under partly cloudy skies about two hours before sunset, was carried by live video feed in a NASA webcast.
"A perfect bullseye splashdown for Integrity and its four astronauts," NASA commentator Rob Navias said moments after the landing.
"We are stable one - four green crew members," mission commander Reid Wiseman radioed just after splashdown, signalling the capsule was steady and that all four astronauts were in good shape.
It took NASA and US Navy recovery teams less than two hours to secure the floating capsule and retrieve the four crew members - US astronauts Wiseman, 50, Victor Glover, 49, and Christina Koch, 47, along with Canadian astronaut Jeremy Hansen, 50. NASA reported that a navy medical officer who briefly checked the astronauts aboard the capsule found them all to be healthy.
It followed a white-knuckle, fiery plunge as Orion barrelled into Earth's atmosphere at nearly 33 times the speed of sound, generating frictional heat that sent temperatures on the capsule's exterior soaring to some 2760C.
The tension broke as contact was re-established and two sets of parachutes were seen billowing from the nose of the free-falling capsule, slowing its descent to about 25km/h before Orion gently hit the water.
Once Navy divers had attached a floating collar to stabilise the capsule, the four astronauts, still wearing their orange flight suits, were helped onto an inflatable raft. From there, they were hoisted one by one to helicopters hovering overhead and flown a short distance to nearby Navy amphibious transport vessel, the John P. Murtha, for further medical examination.
Glover and Koch smiled broadly and waved toward cameras as they sat on the edge of a helicopter door on the flight deck.
The crew was expected to spend the night aboard the ship and be flown on Saturday to Houston, where they will be reunited with family, NASA said.
The quartet blasted off from Cape Canaveral, Florida, on April 1, lofted into an initial Earth orbit by NASA's giant Space Launch System rocket before sailing on for a rare journey around the far side of the moon.
In so doing, they became the first astronauts to fly around Earth's only natural satellite since the Apollo program of the 1960s and 70s. Glover, Koch and Hansen also made history as the first Black astronaut, the first woman and first non-US citizen, respectively, to take part in a lunar mission.
At the flight's peak, the Artemis astronauts reached a point 406,771km from Earth, exceeding the previous record of 399,117km set in 1970 by the crew of Apollo 13.
The voyage, following the uncrewed Artemis I test flight around the moon by the Orion spacecraft in 2022, marked a critical dress rehearsal for a planned attempt later this decade to land astronauts on the lunar surface for the first time since Apollo 17 in late 1972.
Last week's successful launch was a major milestone for the SLS rocket, handing its principal contractors, Boeing and Northrop Grumman, long-sought validation that the launch system more than a decade in development was ready to safely fly humans to space.
