In physics, opinions don't matter, only demonstrated experiments. The day the fellow succeeds, if ever, he won't need anybody else's opinion.

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.'

A conspiracy theorist is a person who tacitly admits that they have insufficient data to prove their points. A conspiracy is a battle cry of a person with insufficient data.

There are photons that have been traveling for 30,000 years, and I'm... snatching them from this journey and planting them into my digital detector. And then I started feeling bad for the photon, and I said maybe it wanted to continue but I got in its way. But then I said, no, those are probably happier photons than the one that slammed into the mountainside that will go unanalyzed and will not contribute to the depth of our understanding of the universe.

God is an ever-receding pocket of scientific ignorance that's getting smaller and smaller and smaller as time moves on.

If humans one day become extinct from a catastrophic collision, there would be no greater tragedy in the history of life in the universe. Not because we lacked the brain power to protect ourselves but because we lacked the foresight. The dominant species that replaces us in post-apocalyptic Earth just might wonder, as they gaze upon our mounted skeletons in their natural history museums, why large headed Homo sapiens fared no better than the proverbially peabrained dinosaurs.

I don't want to make a member of Congress do something that that member of Congress's constituents would not approve of, or would not agree to. So in that regard, I'm kind of the opposite of a lobbyist.