If you took every nuclear weapon ever built at the height of the Cold War, lumped them together and blew them up at the same time, that would be one one-millionth of the energy released at that moment.

The best idea ever thought of in the history of humanity is useless unless someone communicates it. It will die in the test tube. And in our case, what we're communicating here to people is not necessarily something they want to hear. And so, our demeanor - how we deliver this message - takes on crucial, crucial importance.

Humanity and life are reflected in the stars, and the Universe itself is poetry.

You can experience the thrill of discovery, the incredible, visceral feeling of doing something no one has ever done before, see things no one has ever seen before, know something no one has ever known before. ... Welcome to science, you're gonna like it here.

When you're dealing with the universe, ignorance can be deadly.

If a little kid ever asks you just why the sky is blue, you look him or her right in the eye and say, 'It's because of quantum effects involving Rayleigh scattering combined with a lack of violet photon receptors in our retinae.'

The difference between the dinosaurs and us is that we have a space program and we can vote...