In all of the movie portrayals, a spacewalking suit seems sort of insignificant, like a pair of shorts and a T-shirt. No one thinks much about it. But it's a spaceship, not a spacesuit, an entire life-support mechanism that's incredibly complex and cumbersome. It's very difficult to put on and off. You have to run it the whole time you are wearing it, and it redefines how you move. It's like if you put on a wetsuit and a snowmobile suit and froze yourself solid and then tried to go and do work.

Remember, nobody changes the world on their own.

If you start thinking that only your biggest and shiniest moments count, you're setting yourself up to feel like a failure most of the time.

Doing a space walk. It is one of the most rare human experiences. To leave your spaceship and go outside, so that you are alone in the universe with Earth distant and the universe around you. That is amazing.

It’s not enough to shelve your own competitive streak. You have to try, consciously, to help others succeed.

Anticipating problems and figuring out how to solve them is actually the opposite of worrying: it's productive.

Spaceflight isn't just about doing experiments, it's about an extension of human culture.