Chris Hadfield

Spacewalking trumps everything. Viscerally, it is a phenomenal place to be; to be able to glance right and see the world, glance left and see the universe, and realise for a moment that you're holding on to your known existence with one hand. That's the thing.

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'm really looking forward to it, if you can imagine floating weightless, watching the world pour by through the big bay window of the space station playing a guitar; just a tremendous place to think about where we are in history.

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.

Our role is to develop techniques that allow us to provide emergency life-saving procedures to injured patients in an extreme, remote environment without the presence of a physician.

Cynicism is the easiest of all reactions, right? But it's also so disappointing and self-defeating.

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.

Nothing focuses your mind quite like flying a jet. That's one reason NASA requires that astronauts fly T-38s: it forces us to concentrate and prioritize in some of the same ways we need to in a rocket ship.

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.

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.

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.