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- NASA astronaut Scott Kelly answers questions during a news conference at the Johnson Space Center. (Photo Credit: Anish Banskota)
- Astronaut twins Scott and Mark Kelly are participating in a study on the effect of space on the body.
- Mark Kelly and NASA researchers answer questions at a news conference at Johnson Space Center. (Photo Credit: Anish Banskota)
340 days — that's how long Scott Kelly lived in 14,000 cubic feet in space. That's as long as any American astronaut has spent on the ISS.
He and his Russian counterpart Mikhail Kornienko landed safely in Kazakhstan on Tuesday and Kelly arrived in Houston Thursday morning.
Friday was the first time he spoke publicly about the mission at Johnson Space Center. He said he was surprised how long that year felt.
"It seemed like I lived there forever. It seemed longer than I thought it would be," Kelly said. "But I did, having flown before, I did pace myself appropriately, so I felt pretty good about that."
The one-year mission is considered key for future missions to Mars.
Most prominently, Scott Kelly and his twin brother and former astronaut Mark Kelly took part in a study to compare the effects of space on the human body and mind.
"I did an MRI yesterday, I have another one tomorrow," Mark Kelly said, listing just a few of the tests he has been part of. "There's a test where they reduce the pressure around your lower extremities to look at the function of your circulatory system."
John Charles, a scientist with NASA's human research program, explained the purpose of the twins study.
"By looking at Mark's results collected over the course of the year, we can see what the normal variations might be," he said. "And then by looking at Scott's collected over the course of the year, we can see where his variations are greater than Mark's have been. And those will tell us what areas to investigate in the future."
Charles said NASA will continue to conduct tests with the twins for about the next nine months. He expects first results in a year from now.
Despite his record, Scott Kelly says he doesn't consider himself a "poster boy for Mars."
"It just so happens that I was the first person to do this and it doesn't necessarily mean I'm the best or would be better than anyone else," he said. "I think we have a lot of very talented and dedicated people in our office."
NASA aims to send the first humans to Mars in the 2030s.