People say, oh we just need charismatic leaders to continue on to Mars. Now we've gone to the moon, of course Mars is next. No. Mars was never, of course, next. It is next if you think we went to the moon because we're explorers, but if you know we went to the moon because we were at war then we're never going to Mars. There's no military reason to do it, to justify the expenditure.

Plenty of people get excited about the universe.

Our entire universe emerged from a point smaller than a single atom. Space itself exploded in a cosmic fire, launching the expansion of the universe and giving birth to all the energy and all the matter we know today. I know that sounds crazy, but there’s strong observational evidence to support the Big Bang theory. And it includes the amount of helium in the cosmos and the glow of radio waves left over from the explosion.

You ask people, do you pray to [a person or] God. If you say yes to that, you're religious by, presumably, anybody's standards of your conduct. And it's the yes to that question that applies to 40% of scientists. So, there're plenty of atheists who are scientists or not scientists. There maybe a conflict but many people in this country coexist in both worlds.

On Friday the 13th, April 2029, an asteroid large enough to fill the Rose Bowl as though it were an egg cup will fly so close to Earth that it will dip below the altitude of our communication satellites. We did not name this asteroid Bambi. Instead, we named it Apophis, after the Egyptian god of darkness and death.

'Cause a musician, you can't tell me, "I've got this message I want share with the public," and it's three-and-a-half minutes long. That's not it. If your message is only three-and-a-half minutes long, then we got nothing else to talk about. Because life is more complex than three-and-a-half minutes.

How many times have you heard a person in a workplace say, "I wasn't trained for this!" That's an impossible reaction from a physicist, who would say, instead, "Cool. A problem I've never seen before. Let's see how I can figure out how to solve it!"