The remarkable feature of physical laws is that they apply everywhere, whether or not you choose to believe in them. After the laws of physics, everything else is opinion.

As a scientist, I want to go to Mars and back to asteroids and the Moon because I'm a scientist. But I can tell you, I'm not so naive a scientist to think that the nation might not have geopolitical reasons for going into space.

Next time you're stunned by a large moon on the horizon, bend over and view it between your legs. The effect goes away entirely.

When I was a kid, I thought that if everyone looked up the way I did then everyone would want to study the universe just like me - how could they not? This naiveté is what tells me that my interest was more a calling than a rational comparative assessment about what to be when I grew up.

Typically, when you look for role models, you want someone who has your interests and came from the same background. Well, look how restricting that is. What people should do is take role models a la carte. If there's someone whose character you appreciated, you respect that trait.

It's progress I think, that science has joined philosophy, metaphysics & religion as subjects drunk people argue about in bars.

I lose sleep at night wondering whether we are intelligent enough to figure out the universe. I don't know.