Meet Scott Kelly, the astronaut who just spent a year in space

One year ago, NASA astronaut Scott Kelly lifted off for the International Space Station. (He hitched a ride aboard the Russian Soyuz rocket, because NASA doesn’t fly its own manned rockets anymore.)

One year: That’s the longest any American has ever been in space.

He spent the time working, exercising, and posting a year’s worth of stunning photos and fascinating updates on Twitter and Instagram.

And Tuesday he returned to Earth. (The landing was broadcast live on NASA’s website.)

To bring you up to speed on who he is and what he was doing up there, here’s an excerpt from my interview with Kelly from a CBS Sunday Morning profile of him that we filmed just days before his liftoff. (You can watch that story here.) The day before he departed for Russia, he invited the CBS crew and me to breakfast at his home with his girlfriend, NASA public affairs executive Amiko Kauderer.

POGUE: So, a year in space. Is this just because it’s there? Or is it preparation for Mars?

KELLY: I think it’s mostly in preparation for going to Mars or somewhere else that’s going to take us much longer than what our current experience base is. And in the United States, that’s 220 days.

POGUE: Did the fact that you’re an identical twin [of former astronaut Mark Kelly, husband of Rep. Gabby Giffords] influence your selection?

KELLY: Actually, that was not something that was discussed until after I was picked for this flight. I asked, “So if a reporter or somebody asks about doing comparative research between my brother and me, how should I answer that question?”

And the answer I got was, “We’re not considering doing anything like that. So just be honest about it.”

But then they thought about it: You know, actually, we have all this data on my brother; we’re identical twins. Maybe there is some merit in doing a genetic study between the two of us. And they put out requests and got a lot of interest.

POGUE: So he’s going to be sort of the control on the ground?

KELLY: Yes.

POGUE: What will you be doing for a year up there?

KELLY: We do a lot of science on the space station. Over the course of the year, there’ll be 400 to 500 different investigations in all different kinds of disciplines. Some are related to improving life on earth in material science, physics, combustion science, earth sciences, medicine. And then there’s exploration-related science: expanding our ability to live and work in space. And then also a part of this is this whole genetic component with my brother and me.

POGUE: What will be the hardest part of the year?

KELLY: Floating is a unique experience, the view is great. But like anywhere else, if you’re somewhere for a long period of time and you can’t leave, eventually you get tired of being there. You feel very privileged to be able to participate in the program, but at some point you get to the point where you feel like you want to come home.

It’s about four months in when you start feeling like, “Hey, I’m happy to stay — and I’m committed to staying obviously, because I have no choice — but I kind of feel like I could come home now and I’d be very satisfied.”

POGUE: What about the physical changes? Do you worry about your eyesight?

KELLY: A little bit. I don’t expect I would come back blind from from space. But it’s quite possible there are effects that could be detrimental to your ability to do certain activities, especially on a mission to Mars. We really need to understand [why eyesight deteriorates in zero gravity] better.

We do know that exercise and certain drugs help in our ability to prevent bone loss, but we think there is also a restructuring of bone that goes on. So even though your overall bone density may not have changed much, it’s a different structure of bone; it’s weaker.

There’s muscle loss, there’s effects on our immune system. But I would say that our biggest risk is probably vision and radiation issues. Those would be my primary concerns.

POGUE: What kind of communication will you be able to have with your family?

KELLY: We have email onboard that now is pretty much live, which is very nice. Last time I was up there, it wasn’t that way. We would sync up our mailboxes only a few times a day.

We also have a phone that’s kind of like making a Skype call. And we have the the antenna coverage to sync the mail up and make a phone call about every 45 minutes. We can have video chats on the weekends.

POGUE: NASA organizes your life pretty carefully when you’re up there, right? Do you have free time? Do you look forward to free time? Or are you just as glad to be scripted?

KELLY: I think some free time is important. Too much would not be good. It’s better to be overworked than underworked in that environment.

For me, one of the things that’s most fatiguing about flying in space for a long period of time is the fact that you are scheduled throughout your waking hours, even on your days off. So your mindset is: “I’m always having to think ahead to what I have to do next.” Like, you know, in 15 minutes, I gotta go work on this piece of hardware. So it’s always, like, what the next thing is. And the other aspect of that is you’re always at work. You wake up, you’re in your office; you go to sleep, you’re in your office. You never leave.

And then as soon as you get home, you don’t have that anymore. So it’s like, “OK, well, what do I do? I’ve got no one telling me what to do.” So it’s almost feeling like you’re a little bit aimless. And it’s an odd place to be.

POGUE: This is all about to become real. So where are you emotionally? Is the launch date like Christmas? Or is it like going to work?

KELLY: I have four days left in the United States. I’m pretty much ready to go. I feel pretty ready.

But I definitely feel different than I did last time. Last time, I felt like I was kind of taking a long business trip. This time it’s more like I feel like I’m just moving and I’m not coming back.

POGUE: You sometimes hear naysayers saying like, “Oh my God, this many million dollars a day in space for this mission, we should spend that on Earth!”

KELLY: NASA’s budget this year is $18 billion. I think about $5 billion is for human spaceflight. But a lot of people think that NASA’s budget is equivalent to the Department of Defense’s half-trillion-dollar budget. It’s not. What we spend on human space flight is half a penny for every tax dollar.

And what we get for that investment, I think, is huge. It improves our technology, our quality of life on Earth. There are so many things we have now and that we use in our everyday lives that NASA missions developed.

There’s also the educational aspect of it — having these young kids being interested in science and math and later growing up to be engineers and scientists, and how that improves our economy.

And the last thing I say to them is that all that money is spent here on Earth. I was on that space station for six months, and I didn’t see any money there (laughs).

POGUE: Do you miss the shuttle?

KELLY: The shuttle was a very capable vehicle. And it could do so many things: launch large payloads into orbit, bring large payloads back to the ground, bring people up, allow us to repair satellites, do science experiments. But you know, with that capability came a lot of expense and a lot of sophistication.

POGUE: Everybody asks you, “My God, you’re about to head out for a year. What are your final thoughts?” Do people make too much of it? Or are you just showing up for work another day?

KELLY: I think a lot of people at work aren’t sure when my last time in my office is. So it’s a little bit awkward. I get some people saying, “Hey, goodbye, see you in a year” — or me saying that to them. And others probably think they’ll have that opportunity yet to come.

We will have a little farewell thing the night before I leave for Russia, at a local place. So hopefully I’ll get to say goodbye to everyone.

POGUE: Is there anything in your gut that’s like, “Oh my God”?

KELLY: Not really. Most of my concerns with this flight and being gone for a year is the stuff that could happen to people on Earth while I’m gone. I experienced that with Gabby last time. [Rep. Gabby Giffords, Scott’s sister-in-law, was shot while he was on the Space Station on a previous mission.]

POGUE: And how about you, Amiko? Are you like the wives of Apollo 13 who look up and worry every day?

KAUDERER: I worry. But I know what he worries about. And so my job is to ease any issues that he may have. I try to be a lot more cognizant about my own health and taking care of myself and my well-being and the people around me. And caring for his father and his daughters if they call on me or anything like that. That’s really what I try to do. I’m his supporter.

KELLY: Cheerleader.

KAUDERER: I am the cheerleader (laughs).

POGUE: I can’t imagine that it would be easy.

KAUDERER: It’s not. It’s not easy at all. But the mindset is, we really appreciate challenge, because we know that at the end of it, you can go, “Yeah, we did that.” You know?

KELLY: And the homecoming’s really good after a year (laughs).

David Pogue is the founder of Yahoo Tech; here’s how to get his columns by email. On the Web, he’s davidpogue.com. On Twitter, he’s @pogue. On email, he’s poguester@yahoo.com. He welcomes nontoxic comments in the Comments below.