Astronaut Scott Kelly Could 'Go Another Year If I Had to' in Space

PHOTO: Scott Kelly conducted the final press conference from space for his one year mission.PlayNASA
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Astronaut Scott Kelly said today he's excited to return to Earth to see his family after a year-long mission but added he has enough stamina to double his stay in space.

"I could go another year if I had to," Kelly said this afternoon during the mission's final news conference from space. "It would just depend on what I was doing and if it made sense."

Kelly signed up for the one-year mission to help NASA better understand what happens to an astronaut's physical and mental health during a prolonged stay in a micro-gravity environment. Kelly's results will be compared with his identical twin brother, retired astronaut Mark Kelly, who is serving as the control subject on Earth.

The results will help inform a future mission to Mars or another deep space destination. While he's in good spirits, Kelly said he has noticed some differences in the way he feels.

"It's somewhat of a harsh environment," he said of life in space. "You don’t feel perfectly normal. There is always a lingering something you feel or it's just not normal. ... Having said that, it's not necessarily uncomfortable."

The hardest part, Kelly said, is the "loss of connection in a physical sense" from loved ones on Earth. He said one way life can improve for astronauts, including those who travel on a future mission to Mars in even smaller quarters, would be "making that private area as perfect as possible."

Riding in a Russian Soyuz spacecraft, Kelly is scheduled to land in Kazakhstan at 11:27 p.m. ET next Tuesday. As soon as he returns to Houston, Kelly said NASA will put him through a battery of tests to measure any changes in his health.

Immediately after that, he said he already knows what he'll be doing.

"I'm going to go home and jump in my pool," he said.