"Every single thing that you learn really just gives you more comfort. It's something I counsel kids all the time: if someone is willing to teach you something for free, take them up on it. Do it. Every single time. All it does is make you more likely to be able to succeed. And it's kind of a nice way to go through life."

"Just taking risks for risk's sake, that doesn't do it for me. I'm willing to take risks that I think are worth it, and I've worked so hard to make sure that I survive."

"Navigation in space is hard. On Earth there are references to go by, things to look at, roads to follow. The problem is worse in orbit since we're going so fast - a small error gets worse quickly at 8 km/sec. We navigate using reference to the Earth and the stars, have a computer onboard that tracks our speed and direction, and constantly updates."

"The best simulator for spacewalking is underwater - it allows full visuals and body movement in 3D. Virtual reality is good, too, and has some advantages, like full Station simulation, not just part. Like all simulators, they have parts that are wrong and misleading: an important thing to remember when preparing for reality."

"Every two years the American politics industry fills the airwaves with the most virulent, scurrilous, wall-to-wall character assassination of nearly every political practitioner in the country - and then declares itself puzzled that America has lost trust in its politicians."

"When you're dealing with machines or anything that you build, it either works or it doesn't, no matter how good of a salesman you are."

"I enjoyed L.A. because it was nice to be in the sunshine and live in a house with proper wardrobes. I loved the space."

"It definitely has learning a lesson about the way you're living your life. I wouldn't compare our movie to that, but it has a structure where it's about a man who doesn't appreciate all that he has and finds out at the end that life has been great and he has to enjoy that."