What I’m saying is, when different experiments give you the same result, it is no longer subject to your opinion. That’s the good thing about science: It’s true whether or not you believe in it. That’s why it works.

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.

We live in a world where not everyone has the urge to help others... It is OK to encourage others to pull themselves up by the bootstraps, but if you do, just remember that some people have no boots.

The history of exploration across nations and across time is not one where nations said, 'Let's explore because it's fun.' It was, 'Let's explore so that we can claim lands for our country, so that we can open up new trade routes; let's explore so we can become more powerful.'

Whether or not you can become great at something, you can always become better.

I was born the same week NASA was founded, so we're the same age and feel some of the same pains, joys, and frustrations.

Do you realize that if you fall into a black hole, you will see the entire future of the Universe unfold in front of you in a matter of moments and you will emerge into another space-time created by the singularity of the black hole you just fell into?