Science is not just 'Here are some facts, learn that'. There's a thread through these stories that, if you know how to tell it because you know how they connect, then it's a thread that will land right in your mind, body and soul.

Three and a half million years ago our ancestors - yours and mine - left these traces [indicates footprints]. We stood up and parted ways from them. Once we were standing on two feet, our eyes were no longer fixated on the ground. Now, we were free to look up and wonder.

I'm often asked whether I believe in Global Warming. I now just reply with the question: "Do you believe in Gravity?"

One of the things that fascinates me most is when people are so charmed by the universe that it becomes part of their artistic output.

Photography is a form of time travel.

If a scientist is not befuddled by what they're looking at, then they're not a research scientist.

Everyone has all different experiences in school. I just know that throughout my life, at no time did any teacher ever point to me and say, hey. He'll go far.