“Almost everything worthwhile carries with it some sort of risk, whether it's starting a new business, whether it's leaving home, whether it's getting married, or whether it's flying in space.”

“It is spectacular. From about five minutes in, when we knew for sure that we were going to have the weather to go, the smile on my face just got bigger and bigger, and I was just beaming through the whole launch. I mean, it is just an amazing ride.”

“The communities and countries best at using energy to optimize a microclimate for human life are also the ones whose people have the longest average lifespans. Canada, Sweden, and Iceland - places with inhospitable winter weather - are frontrunners in sustaining human health and life.”

“I think there are lots of ways to exercise ambition and accomplish things using leadership without going into elected politics. So, categorically, I have no intention of going into elected politics. None.”

“You should have a fear of some things. That doesn't mean it incapacitates you from your ability to figure out a way to deal with it.”

“A lot of people live in fear because they haven't figured out how you're going to react when faced with a certain set of circumstances. I've come to terms with this by looking deeply into whatever makes me fearful - what are the key elements that get the hairs up on the back of my neck - and then figuring out what I can do about it.”

“I've had a chance to see something that is way outside everybody else's frame of reference and gives a perspective that is very different from everyone else's.”

“I've had a chance to fly a lot of different airplanes, but it was nothing like the shuttle ride.”

“Ultimately, leadership is not about glorious crowning acts. It's about keeping your team focused on a goal and motivated to do their best to achieve it, especially when the stakes are high and the consequences really matter. It is about laying the groundwork for others' success, and then standing back and letting them shine.”

“For the last several years and culminating in six months in orbit next year, I've been training for my third space flight. This one is almost in a category completely different than the previous two, specifically to live in on the space station for six months, to command a space ship and to fly a new rocket ship.”

“I've been lucky enough to fly to space twice.”