The day we stop exploring is the day we commit ourselves to live in a stagnant world, devoid of curiosity, empty of dreams.

I want to create the airplane that flies in the rarified atmosphere of Mars. This is what galvanizes a generation to want to become scientists and engineers in the first place, not we need a scientist to develop a plane that's 20 percent more fuel-efficient than the one your parents flew.

When you're advancing a frontier it stimulates creativity to find solutions.

The day that you stop looking - because you're content God did it - I don't need you in the lab. You're useless on the frontier of understanding the nature of the world.

The Earth is just one place of many that we could hang our hats.

If you want to assert a truth, first make sure it's not just an opinion that you desperately want to be true.

There's a lot of memorization that goes on in school. You memorize vocabulary words and all these sorts of things.