SAN DIEGO, United States (AFP) — An elated NASA late Friday was celebrating its successful voyage around the Moon, after four astronauts safely returned to Earth having completed the first lunar flyby in more than 50 years.

The NASA spacecraft carrying four astronauts — three Americans and one Canadian — splashed down without a hitch off the California coast, capping the US space agency’s crewed test mission that returned with spectacular images of the Moon.

“What a journey,” said mission commander Reid Wiseman, who reported that the crewmembers — himself along with Christina Koch, Victor Glover and Jeremy Hansen — were “stable” and “green.”

“They’re in great condition, that’s what that means,” said Rob Navias, the NASA public affairs official who narrated their return on the agency’s livestream.

Following an expected but nerve-wracking communications blackout during their high-stakes re-entry, Wiseman’s voice triggered relief that the astronauts were well on their way back home.

“We have you loud and clear,” he said following a voice check from mission control in Houston.

NASA personnel and the US military helped extract the astronauts from the bobbing capsule — to the applause of those watching from mission control.

By late Friday, helicopters had lifted the astronauts to a recovery ship off the Pacific coast near San Diego, where they all proved capable of walking unassisted.

NASA administrator Jared Isaacman called the voyage “a perfect mission.”

“We’re back in the business of sending astronauts to the Moon,” he said, and “this is just the beginning.”

‘A great day’

As the astronauts returned to Earth their spacecraft reached maximum speeds more than 30 times the speed of sound, and faced searing temperatures around half as hot as the surface of the Sun.

It was a key test of their heat shield, which in an earlier trial uncrewed mission had faced complications that they attempted to mitigate this time around by shifting the return trajectory.

“If you didn’t have anxiety bringing this spacecraft home, you probably didn’t have a pulse,” said flight director Rick Henfling.

But the Artemis II reentry was smooth sailing.

The Orion capsule will now be painstakingly examined to assess how it fared.

US President Donald Trump praised the astronauts for their “spectacular” trip and said he “could not be more proud” — while wasting no time in looking ahead to the eventual goal of sending missions even further into space.

“Next step, Mars!” he wrote on social media.

Artemis II was the inaugural crewed mission of NASA’s program aiming to install a sustained presence on the Moon, including the eventual construction of a base that could be used for further exploration including to Mars.