When I stand on the edge of a cliff or right at the edge of a building or something, it's one of the few things that gives me kind of a deep, overwhelming, irrational fear where it affects my physiology.

Do your homework in advance about the actual travel details so transportation issues do not define your holiday.

Competence means keeping your head in a crisis, sticking with a task even when it seems hopeless, and improvising good solutions to tough problems when every second counts. It encompasses ingenuity, determination and being prepared for anything.

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.

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

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.

As I have discovered again and again, things are never as bad (or as good) as they seem at the time.