Scott Kelly after year in space
NASA astronaut Scott Kelly flashes two thumbs-up signs after his return to Earth from the International Space Station. (Credit: NASA)

Capping off a year in space, NASA astronaut Scott Kelly breathed earthly air for the first time in 340 days today after a successful, safe trip from the International Space Station to the steppes of Kazakhstan.

Since last March’s blastoff from the Baikonur Cosmodrome in Kazakhstan, the 52-year-old Kelly circled the planet more than 5,440 times, saw more than 10,800 orbital sunrises and sunsets, and put almost 144 million miles on his cosmic odometer.

The mission set a U.S. record for continuous spaceflight and blazed a trail for much longer trips to Mars and back. But to get a true sense of how long Kelly has been in space, consider this: The last time he was on Earth, Jeb Bush was the front-runner for the GOP presidential nomination.

Kelly’s Super Tuesday ride began when he climbed into a Russian Soyuz spacecraft along with two crewmates: Russia’s Mikhail Kornienko, who also finished up a 340-day stay; and Sergei Volkov, who has been in orbit for a mere 182 days. The Soyuz backed away from the station right on time, at 5:02 p.m. PT, and landed in Kazakhstan at 8:26 p.m. PT (10:26 a.m. local time March 2).

Kelly flashed a big thumbs-up as he was helped out of the capsule. He seemed to relish the sights and smells of planet Earth, even if the temperature was near freezing.

“The air feels great out here,” NASA spokesman Rob Navias quoted Kelly as saying on the scene. “I have no idea why you guys are all bundled up.”

As is customary after the landing of a long-duration crew, Kelly and the other two spacefliers were carried off for the first of what’s expected to be several rounds of checkups. “The crew’s looking great,” Sean Fuller, NASA’s director of human spaceflight programs in Russia, said after the initial checks.

In the days ahead, researchers will want to find out how Kelly adjusts to Earth’s gravity after spending nearly a year in zero-G. He has already mentioned that his vision has been impaired – which is one of the recognized effects of long-duration spaceflight. It’s also likely that he’s lost some bone and muscle mass.

Kelly’s genetic profile and medical readings will be compared with those of his twin brother, Mark Kelly, a former astronaut who has been undergoing a battery of tests to establish a baseline for judging spaceflight’s effects.

It will take months to analyze the medical data. The findings could point up concerns that will need to be addressed to smooth the way for trips to Mars and its moons in the 2030s.

Meanwhile, life on the space station goes on. On Monday, Kelly handed over command of the space station to fellow NASA astronaut Tim Kopra. “It’s a little bittersweet,” Kelly acknowledged.

“Thank you for your leadership,” Kopra told Kelly. “You’ve been such a great role model to us.”

During the ceremony, Kelly widened the focus of the “Year in Space” experiment to take in more than Kornienko and himself.

“We’ll say something like ‘We did it,’ or ‘We made it,’ but we both recognize that this is a lot more about teamwork and all the people that it takes to put these missions together and be successful than it is about us,” he said. “A really smart person said to me one time, ‘Teamwork makes the dream work in spaceflight.’ Spaceflight is the biggest team sport there is.”

Year in space: change of command ceremony
NASA astronaut Scott Kelly (right foreground) shakes hands with crewmate Tim Kopra during a change-of-command ceremony on the International Space Station. Kelly, who has spent nearly a year in space, handed off command of the space station to Kopra on Monday. (Credit: NASA)

Three replacement teammates – NASA’s Jeff Williams and Russia’s Olek Skriprochka and Alexey Ovchinin – are scheduled to arrive at the station on March 18. Kopra and the other two spacefliers currently living on the station, Britain’s Tim Peake and Russia’s Yuri Malenchenko, are due to finish up their own six-month stint in orbit in June.

Although Kelly’s 340-day stay set a new space endurance record for NASA, the 438-day world record set by Soviet cosmonaut Valeri Polyakov in 1995 still stands.

That mark is almost certain to be exceeded someday – and it’s likely to happen on the International Space Station, during a future “Year and a Half in Space” experiment.

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