Three NASA astronauts and a fourth from the Russian space agency returned to Earth from the International Space Station on Friday morning after weather-related delays.

A NASA astronaut experiencing a “medical issue” was hospitalized early Friday after returning from the International Space Station, the space agency said Friday. Citing privacy, NASA did not identify the astronaut or provide details about the medical issue.

The hospitalized astronaut, who NASA said was “in stable condition under observation as a precautionary measure,” was one of four astronauts who splashed down in the Gulf of Mexico near Pensacola, Fla., at 3:29 a.m. Eastern time at the conclusion of nearly eight months in space.

This mission, the eighth operational flight that SpaceX has undertaken for NASA, was known as Crew-8. The astronauts — Matthew Dominick, Michael Barratt and Jeanette Epps of NASA and Alexander Grebenkin of the Russian space agency Roscosmos — launched in March as part of a regular six-month rotation of crew members on the International Space Station.

The undocking and splashdown occurred without any technical issues. In a video streamed from the deck of the recovery ship, the astronauts appeared to emerge from the capsule without problem, and all four then underwent initial health checks. During a news conference an hour and a half after their return, a NASA official said the crew was “doing great.”

Later in the day, NASA issued an update saying that all four astronauts had been taken to a Pensacola hospital as a precaution. Another update in the afternoon said three of the astronauts had returned to Houston.

The Crew-8 mission was extended by about two months. The postponements started because of problems with Boeing’s troubled Starliner spacecraft, which occupied one of two available docking ports.

The astronauts of Crew-8 could not come home because the SpaceX Dragon vehicle that carried them to orbit took up a second docking port. That left nowhere to dock for the Crew-9 mission that would bring up the next complement of space station astronauts in another Crew Dragon vehicle.

The Crew-8 astronauts thus had to wait in space until after Starliner departed.

NASA decided that the Starliner astronauts would remain in orbit as part of the space station crew, and an empty Starliner successfully returned to Earth on Sept. 6.

Crew-9 with two other astronauts launched three weeks later, paving the way for the Crew-8 astronauts to finally return home.

Then weather intervened, first with Hurricane Milton passing over Florida. Even after the hurricane passed, the weather conditions around Florida remained unfavorable until Wednesday, when the Crew Dragon with the four astronauts undocked.