Science is not there for you to cherry pick ... You can decide whether or not to believe in it but that doesn’t change the reality of an emergent scientific truth.

Any astrophysicist does not feel small looking up at the universe; we feel large.

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.

This influential, yet controversial idea requires that the mixture of species on Earth at any moment acts as a collective organism that continuously (yet unwittingly) tunes Earth's atmospheric composition and climate to promote the presence of life... But I'd bet there are some dead Martians and Venusians who advanced the same theory about their own planets a billion years ago.

Once upon a time, people identified the god Neptune as the source of storms at sea. Today we call these storms hurricanes.... The only people who still call hurricanes acts of God are the people who write insurance forms.

(Space programs are) a force operating on educational pipelines that stimulate the formation of scientists, technologists, engineers and mathematicians... They're the ones that make tomorrow come. The foundations of economies... issue forth from investments we make in science and technology.

I'd go back and hang out with Isaac Newton. I'm torn between do I hang out with him or do I bring him into the present to hang out with me. See, that might be terrifying because his head will just explode once he sees everything that was derived from his discoveries, but I'd spend more time with someone who I think is one of the most brilliant minds our species has ever known.