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

I guarantee if you walk into 100 spider webs, you will have changed your fundamental human behavior. And you can apply this to anything, And figure out a way to reprogram yourself, to change your primal fear.

I'm not a wealthy person and I don't think that I would be able to prioritize that much money to go for a ride to a place that I have already lived. But if the price comes down or I win a lottery or something, why not?

The cool things about space is when you put your pants on here, you can put them on two legs at a time.

My optimism and confidence come not from feeling I'm luckier than other mortals, and they sure don't come from visualizing victory. They're the result of a lifetime spent visualizing defeat and figuring out how to prevent it. Like most astronauts, I'm pretty sure that I can deal with what life throws at me because I've thought about what to do if things go wrong, as well as right. That's the power of negative thinking.

There's really just one thing I can control: my attitude during the journey, which is what keeps me feeling steady and stable, and what keeps me headed in the right direction. So I consciously monitor and correct, if necessary, because losing attitude would be far worse than not achieving my goal.

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.