We only recently figured out the origin of our own moon. And we have some idea of how the Sun and Earth formed, but that's only because modern telescopes empower us to see other stars and planets freshly hatched within gas clouds across the galaxy. As for the origin of life itself, the transition from inanimate molecules to what any of us would call life remains one of the great frontiers of biology.

So when I think of, what is the meaning of life, to me, that's not an eternal unanswerable question. To me it is in arms reach of me every day.

Doing what has never been done before is intellectually seductive, whether or not we deem it practical.

I can tell you about the universe, but she feels it; and when you feel the universe, it has a whole other meaning to you. Otherwise, you just put a Wiki page on camera. You can learn something, but it won't mean anything to you later on.

Robots are important also. If I don my pure-scientist hat, I would say just send robots; I'll stay down here and get the data. But nobody's ever given a parade for a robot. Nobody's ever named a high school after a robot. So when I don my public-educator hat, I have to recognize the elements of exploration that excite people. It's not only the discoveries and the beautiful photos that come down from the heavens; it's the vicarious participation in discovery itself.

It turns out that the history of astrophysics is where we perfected time keeping.

Kids should be allowed to break stuff more often. That's a consequence of exploration. Exploration is what you do when you don't know what you're doing.