Four astronauts bring the red eye home to earth.

On Saturday at 8:35 p.m. Eastern Time, a crew of four – three NASA astronauts and one from Japan’s space agency – pushed off the International Space Station in a capsule built by SpaceX.

“Thank you for your hospitality and sorry for staying a little longer,” said Michael Hopkins, the commander of the Dragon Resilience crew, referring to the flight’s delayed departure. “See you again on earth.”

The astronauts will orbit the planet several times over the next few hours until they pound down in the Gulf of Mexico south of Panama City, Florida early Sunday morning.

NASA has not performed such a nocturnal splash since 1968 when Apollo 8, the first mission to send astronauts around the moon, returned to Earth.

The approximate time to hos down is 2:57 a.m. Eastern Time on Sunday. SpaceX reported in an update on Saturday afternoon that the weather was still favorable for a landing.

The agency has scheduled a press conference with NASA, SpaceX, and other officials at 5 a.m. on Sunday.

NASA and SpaceX have live broadcasts of these events on NASA TV, or you can watch the video in the player embedded above.

It will be a long journey. The astronauts boarded the Crew Dragon and the hatch closed at 6:26 p.m., but then more than two hours passed before the capsule left when the astronauts checked that the capsule called Resilience and the space station were not leaking air. Resilience was autonomously undocked at 8:35 p.m. and then performed a series of engine shots to move away from the space station.

SpaceX confirmed that the engine firings completed at 10:17 p.m. The capsule will now circle the plant until Florida is in the correct position for it to cum in the Gulf of Mexico.

Just before 2am, while preparing to return to Earth, the Crew Dragon will dump what SpaceX calls the spacecraft’s “trunk” – the cylindrical compartment beneath the gumpdrop-shaped capsule. The trunk will burn up in the atmosphere.

Five minutes after the fuselage has been removed, the capsule fires its engines to fall out of orbit.

As soon as the earth’s atmosphere is low enough, parachutes are deployed to gently lower the capsule into the sea.

Spaceships can safely return to earth by sea or land.

In the 1960s and 1970s, NASA’s Mercury, Gemini, and Apollo capsules splashed into the ocean while the Soviet capsules ended their land voyages. Russia’s current Soyuz capsules continue to land on the ground, as does China’s astronaut-bearing Shenzhou capsules.

NASA returned to water landings on August 2, 2020 when the first crew to return to Earth in a SpaceX Crew Dragon capsule – the same one that brought astronauts to the space station last week – pelted near Pensacola, Florida.

Returning from the vicinity of orbit in free fall to the normal forces of gravity on Earth is often confusing for astronauts. Landing in water increases the possibility of seasickness.

During a press conference last year, Douglas Hurley, a member of the previous crew who completed a water landing in the SpaceX capsule, said he had read reports from astronauts from NASA’s Skylab missions, some of which had water landings before him. “There were some challenges after the hosed down,” he said. “People haven’t been feeling well, and you know that’s how it is with a water landing, even if you’re not as deconditioned as we will be.”

Mr. Hurley admitted that vomiting would not be unexpected.

“There are bags when you need them and we have them on hand,” he said. He added, “If this had to happen, it would certainly not be the first time this has happened in a spacecraft.”

American spaceships have not made a night water landing by astronauts since Apollo 8, NASA says.

This crew arrived before dawn on December 27, 1968, about 1,000 miles southwest of Hawaii. The Times called it “pinpoint hosing” the next day, noting that the crew stayed in their capsule for about 90 minutes before being fished out of the Pacific by a helicopter team from the USS Yorktown. William Anders, the mission’s lunar module pilot, said over the radio in the capsule: “Get us out of here, I’m not the sailor on this boat.” (James Lovell, his crewmate, had been a captain in the US Navy.)

SpaceX rehearsed the work during the night and in January successfully recovered a cargo capsule that spilled in the Gulf of Mexico west of Tampa Bay.

One benefit of landing at night could be that there are less likely to be private boats around. That was a problem in August when the earlier SpaceX capsule splashed down. More than a dozen boats – one flying the flag of a Trump campaign – converged on the scorched capsule, and some took a closer look.

The episode raised concerns about security measures to NASA and SpaceX representatives. If there had been an emergency, NASA officials said the private boats might have hampered recovery efforts. They added that there may have been toxic fumes from the capsule that posed a risk to boaters.

To avert such a result, this time around the Coast Guard will set up an 11.5-mile safety zone around the splash guard point and drive away any intruders.

Typically, the risk of space debris hitting a spaceship going to or from the space station is low. It’s a pretty short journey in general – about a day – and a starship like Crew Dragon is pretty small, so it’s not a big destination for a wayward piece of debris.

But when another group of astronauts, Crew-2, took off in a different Crew Dragon last week, they were a bit scared when mission control at SpaceX’s California headquarters told them that a piece of debris was approaching. They put their spacesuits back on and sat back in their seats in the event that the spaceship was hit, which could depressurize the capsule.

Mission control then provided a reassuring update: Further analyzes showed that the approach of the space debris was not that close after all. Even so, as a precaution, the astronauts waited until they were told that the space debris had passed.

The next day, a NASA spokesman said the debris passed 28 miles away – not very close at all.

Then the United States Space Command, which is tracking orbiting debris, made a more confusing update: the piece of debris that the Crew Dragon supposedly passed did not exist at all. A Space Command spokeswoman said a review was ongoing to determine what caused the false warning.

There are four astronauts in Crew-1:

Victor GloverThe 45-year-old, who was selected as an astronaut by NASA in 2013, is in his first space flight. He is also the first black NASA astronaut to serve on a space station crew.

Michael S. Hopkins, 52, a United States Space Force Colonel, is the commander for the flight. (Colonel Hopkins is also the first member of the newly created US Space Force to go into space.) He was one of nine astronauts selected by NASA in 2009. Spend 166 days in orbit.

Soichi NoguchiThe 56-year-old astronaut at JAXA, the Japanese space agency, is completing his third voyage into space. He was a member of the crew of the space shuttle Discovery in 2005 on the first shuttle launch after the loss of Columbia and its seven astronauts more than two years ago.

During this visit to the International Space Station, Mr. Noguchi made three space walks. This included tests that tested techniques that could repair damage to the shuttle’s thermal tiles, similar to what Columbia did when it reentered Earth’s atmosphere. In 2009/10 he spent five months in orbit as a member of the space station crew.

Shannon WalkerThe 55-year-old was already working on the space station in 2010. Dr. Walker received her PhD in space physics from Rice University, where she studied how the solar wind interacts with the atmosphere of Venus.

The space station has been a little more crowded than usual since another SpaceX Crew Dragon capsule, Endeavor, docked on Saturday, April 24th. With this, the crew of Station 11 reached the largest number of astronauts on board since the space shuttles stopped flying (the record for most on board is 13). The four astronauts leave seven astronauts behind – three from NASA, two from the Russian space agency Roscosmos, one from the European Space Agency and one from JAXA.

But while they were there, they conducted scientific experiments, including tissue chips that mimick human organs and growing radishes and other vegetables. They also went on space walks to install equipment on the outside of the space station, including preparation for new solar panels.

And just before they left, Mr. Glover was celebrating his 45th birthday in orbit.

Other astronauts also enjoyed their final moments in orbit with pictures posted on Twitter.

If the landing resembles the return last August, SpaceX personnel will go to the capsule, check that it is intact and free of toxic propellant, and retrieve the parachutes.

A larger salvage ship pulls the capsule out of the water. The hatch is then opened to allow the four astronauts to exit.

After medical examinations, the astronauts will go ashore. From there they fly to Houston. The capsule will be taken to Cape Canaveral, where it will be refurbished for another flight into space.