Photography is a form of time travel.

When I needed to overcome the low expectations of others or the bias that would be expressed in one circumstance or another, I'd keep on keeping on. And I climb over the obstacle, go around it, dig under it, fly over it. That's what kept me going. Otherwise I would have never been an astrophysicist.

In the animal kingdom, one of the keys to survival is to outwit your enemies. And when you're surrounded by carnivores, one of the best strategies is to fade into the background and disappear.

Society needs to see science not as a luxury of funding but as a fundamental activity that drives enlightenment, economics, and security.

I suppose I can live with missing decimals, missing floors to tall buildings, and floors that are named instead of numbered. A more serious problem is the limited capacity of the human mind to grasp the relative magnitudes of large numbers. Counting at the rate of one number per second...to count to a trillion takes 32,000 years, which is as much time as has elapsed since people first drew on cave walls.

We still refer to sunrise, sunset. That only has meaning if you think that Earth is in the center of things, and everything is moving around us. So even though we know intellectually Earth goes around the sun, the language is still pre-Copernican, as we would call it.

Nothing is a thing: it's nothing. So I can imagine a place where there's not even nothing.