Intermediate 
Himalayan lakes, spacewalks and the US presidential campaign helped Scott Kelly stay sane during his 340 days in space, the astronaut told journalists after he landed back on Earth from a record-breaking mission. It seemed like I lived there forever, Kelly said. He had been on several previous missions but said that his biggest surprise was simply how long this one felt. Maybe, occasionally, you do go bananas, he said.
Kelly and a Russian colleague, Mikhail Kornienko, spent nearly a year on the International Space Station (ISS) in order to study the effects of weightlessness, radiation and the cramped conditions of space ight on humans. NASA considers this research essential for a future mission to Mars.
Kelly said the length of the mission was its biggest challenge and that he felt much more sore when he returned to gravity than after shorter trips. Kelly and his twin brother, Mark, a retired astronaut, have spent the last year taking physical and mental tests. The tests will continue, to help NASA learn about how the body copes with the severe strains of space ight.
He said the discomfort of returning to gravity took nothing from the sense of wonder he felt after he landed back on Earth. When the Russian capsule opened on to the cool air of Kazakhstan, Kelly said, he smelled a fragrance like a plant was blooming in that area. It was the fresh air mixed with the charred, kind of sweet smell of a spacecraft that had survived re-entry through the atmosphere.
As he left the spacecraft, he said, the importance of the mission began to sink in: 340 days on a 15-year- old space station which is a million pounds, the size of a football  eld, the internal volume, some say, of a six-bedroom house. The ISS, he said, is a place that uses the power of the sun and was built with the help of an international team.
There are things were going to discover about our experience in space in the space station that we dont even know now, Kelly said, comparing the research of more than 450 missions there to the work done by computer scientists at NASA in the 1960s and 1970s. He added: The view is great, too.
Kelly made the most of that view  he posted spectacular photos on social media of the Earths cities, landscapes, oceans and atmosphere. The Earth is a beautiful planet, he said, describing the beautiful waters around the Bahamas and the rainbow colours of the lakes of the northern Himalayas. He said he would like to visit that region, though he would  rst need to learn what country actually owns them. But, mainly, you just notice how thin the atmosphere is, Kelly added. That, together with these large areas of pollution, is kind of alarming.
The astronaut said he could see entire systems of pollution: smoke clouds from wild res that covered parts of the US, sections of Asia with continuous, visible pollution nearly all year round. He said the message we need to save the planet wasnt completely correct: The planet will get better; its us that wont be here because well destroy the environment. The worlds thin shield of atmosphere makes you more of an environmentalist after spending so much time looking down, he said.
Its for us to take care of the air we breathe and the water we drink. And I do believe we have an impact on that and we do have the ability to change it, if we make the decision to. Kelly was very active on social media, which made many people follow him online. But he said he was unaware of it. Instead, he watched the drama of the 2016 US presidential election.
Besides the news, he said, steady work helped keep him sane: I tried to have milestones that were close, like when is the next crew arriving, the next spacewalk, the next science experiment. That made a difference to me  it kept my sanity. Being back on Earth with the rest of humanity had not quite sunk in, he added. He recalled how shocked he had been to see a crowd of people after a previous mission. Ill soon start feeling that kind of culture shock, he said.
Kelly predicted that he would not  y again with NASA. But I dont think I would ever say Im absolutely, 100%  nished, he added, because of the sudden successes of private space ight companies such as SpaceX. They might need a guy like me someday, he said. Maybe, in the next 20 years, youll be able to buy a cheap ticket, just go for a little visit.