NASA astronaut Scott Kelly is back on Earth.

Kelly and Russian cosmonauts Mikhail Kornienko and Sergey Volkov landed late Tuesday night in the Kazakhstan desert, NASA and Russian mission control said.

Kelly could be seen pumping his fist and giving a thumbs up after being hoisted from the Russian Soyuz spacecraft that brought the trio back.

All three underwent field tests immediately after leaving the spacecraft.

Kelly has completed a nearly yearlong mission on the International Space Station, the longest any U.S. astronaut has been in space.

#Countdown We’re down to a wakeup. #Earth. I’m coming for you tomorrow! #GoodNight from @space_station! #YearInSpace pic.twitter.com/kLe2755XyG

— Scott Kelly (@StationCDRKelly) March 1, 2016

The prolific social media user posted a photo of the sunrise on Tuesday — the last one he watched from space.

Spending 340 days in space could affect a person’s vision and bones, but Kelly said last week that physically, he feels pretty good. “I could go for another 100 days or 100 years,” the astronaut said during his last briefing with reporters from orbit.

After 340 days in space, @StationCDRKelly is back on Earth from his #YearInSpace mission. https://t.co/KX5g7yYnYG https://t.co/dhCfP1M6tZ

— NASA (@NASA) March 2, 2016

But the long stay has also been lonely. “The hardest part is being isolated from people on the ground who are important to you,” he said.

Undocking complete at 8:02pm ET! @StationCDRKelly is on his way home from a #YearInSpace pic.twitter.com/qaPqva0jsU

— NASA (@NASA) March 2, 2016

The space veteran said he has witnessed some of the most amazing scenes of Earth during his mission, like spotting the northern lights, passing over the Bahamas and watching huge storms like Hurricane Patricia.

The view from space

He’s also gained perspective on Earth’s climate while he’s been orbiting the planet. “I feel more like an environmentalist since I’ve been up here,” he said. “There are parts of the Earth that are covered with pollution all the time. I saw weather that was unexpected. Storms bigger than we’ve seen in the past. This is a human effect. This is not a natural phenomenon.”

In a previous interview with CNN, Kelly said Earth’s atmosphere “looks very, very fragile” from the space station. But there are opportunities to solve the Earth’s environmental problems, Kelly said Thursday. “If we can dream it, we can make it so,” he said.

Once Kelly lands, he will be flown to Houston’s Ellington Field and go through a battery of physical and scientific tests. Afterward, he’s looking forward to jumping into his pool, he said.

Kelly isn’t bringing back any souvenirs — this is his fourth mission in space, after all — but he’s looking forward to returning some personal items when he lands.

One of his biggest hopes for the Year in Space mission’s legacy is that it helps NASA on its quest to take astronauts farther away from Earth on longer space flights — a necessity for traveling to Mars in the future. “The space station here is a magical place, and an incredible science facility. I hope more people have the opportunity to do this in the future,” he said.

– CNN