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.

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.

You can't just ignore spacewalking suit; it partially defines the experience. So maybe the most difficult thing is becoming completely attuned to efficiently wearing a garment that is so inhibiting to motion, and making it look effortless, as if it's the most natural thing to be out there on a spacewalk.

Remember, nobody changes the world on their own.

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.

Every single day you're the result of what you did on the days prior.

Decide in your heart of hearts what really excites and challenges you, and start moving your life in that direction. Every decision you make, from what you eat to what you do with your time tonight, turns you into who you are tomorrow, and the day after that. Look at who you want to be, and start sculpting yourself into that person. You may not get exactly where you thought you'd be, but you will be doing things that suit you in a profession you believe in. Don't let life randomly kick you into the adult you don't want to become.