Four astronauts from NASA's Crew-10 mission have returned back to Earth following an almost 18-hour journey after departing the International Space Station (ISS) on Friday aboard a SpaceX Dragon capsule.

US astronauts Anne McClain and Nichole Ayers, Japan's Takuya Onishi, and Russian cosmonaut Kirill Peskov splashed down off California's coast in the Pacific Ocean at 3.33 p.m. UTC/GMT on Saturday.

"From the entire Crew-10, thank you," radioed McClain, the Dragon commander, soon after splashdown. "It was truly the ride of a lifetime."

The crew's return wraps up NASA's 10th commercial crew rotation.

According to the space agency, the four astronauts conducted more than 200 "important and time-sensitive research" experiments over 146 days, including studies on plant growth and cell behavior in microgravity.

Crew-10 replaced stranded astronauts

The Crew-10 mission was launched on March 14, replacing Crew-9, whose members included Barry "Butch" Wilmore and Sunita "Suni" Williams.

Wilmore and Williams were stranded for nine months aboard the ISS after their Boeing Starliner capsule developed propulsion issues.

Eventually, a SpaceX capsule owned by billionaire Elon Musk brought the stranded astronauts home.

Wilmore retired this week after 25 years with NASA, the space agency announced.

Last week, US astronauts Zena Cardman and Mike Fincke, Japan's Kimiya Yui and Russian cosmonaut Oleg Platonov boarded the ISS for a six-month mission.

Edited by Sean Sinico and Wesley Dockery