WASHINGTON, March 16 (Reuters) - A SpaceX capsule

delivered four astronauts to the International Space Station

early on Sunday in a NASA crew-swap mission that will allow a

pair of stuck astronauts, Butch Wilmore and Suni Williams, to

return home after nine months on the orbiting lab.

About 29 hours since launching at 7:03 p.m. ET on Friday

from NASA's Kennedy Space Center in Florida, the Crew-10

astronauts' SpaceX Crew Dragon capsule docked to the ISS at

12:04 a.m. ET (0404 GMT) on Sunday.

They were welcomed by the station's seven-member crew, which

includes Wilmore and Williams - veteran NASA astronauts and

retired Navy test pilots who have remained on the station after

problems with Boeing's ( BA ) Starliner capsule forced NASA to

bring it back empty.

Otherwise a routine crew rotation flight, the Crew-10

mission is a long-awaited first step to bring Wilmore and

Williams back to Earth - part of a plan set by NASA last year

that has been given greater urgency by President Donald Trump

since he took office in January.

Wilmore and Williams are scheduled to depart the ISS on

Wednesday as early as 4 a.m. ET (0800 GMT), along with NASA

astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov.

Hague and Gorbunov flew to the ISS in September on a Crew

Dragon craft with two empty seats for Wilmore and Williams, and

that craft has been attached to the station since.

The Crew-10 crew, scheduled to stay on the station for

roughly six months, includes NASA astronauts Anne McClain and

Nichole Ayers, Japanese astronaut Takuya Onishi and Russian

cosmonaut Kirill Peskov.

The crew-swap mission became entangled in politics as Trump

and his adviser Elon Musk, who is also SpaceX's CEO, urged a

quicker Crew-10 launch. They claimed, without evidence, that

Trump's predecessor Joe Biden had abandoned Wilmore and Williams

on the station for political reasons.

Having seen their mission turn into a normal NASA rotation

to the ISS, Wilmore and Williams have been doing scientific

research and conducting routine maintenance with the other five

astronauts.

Williams told reporters this month that she was looking

forward to returning home to see her two dogs and family. "It's

been a roller coaster for them, probably a little bit more so

than for us," she said.