The chances that your tombstone will read 'Killed by Asteroid' are about the same as they'd be for 'Killed in Airplane Crash.'

Dark matter and dark energy are two things we measure in the universe that are making things happen, and we have no idea what the cause is.

The persistent failures of controlled, double-blind experiments to support the claims of parapsychology suggest that what's going on is nonsense rather than sixth sense.

We didn't go to the moon to explore or because it was in our DNA or because we're Americans. We went because we were at war and we felt a threat.

The universe for me was other planets and other star systems and other galaxies. I enjoyed tracking it, but it had no specific influence on my ambitions for that reason. It wasn't really far enough away from Earth to matter to me.

I try to keep this in mind when tied in to a rope 75 feet up in a tree... The history of ideas about our place in the universe has been a long series of let-downs for those who like to believe we are special.

The center line of science literacy - which not many people tell you, but I feel this strongly, and I will go to my grave making this point - is how you think.