If an alien lands on your front lawn and extends an appendage as a gesture of greeting, before you get friendly, toss it an eightball. If the appendage explodes, then the alien was probably made of antimatter. If not, then you can proceed to take it to your leader.

It's quite literally true that we are star dust, in the highest exalted way one can use that phrase. ...I bask in the majesty of the cosmos. I use words, compose sentences that sound like the sentences I hear out of people that had revelation of Jesus, who go on their pilgrimages to Mecca.

Science is a philosophy of discovery. Intelligent design is a philosophy of ignorance. You cannot build a program of discovery on the assumption that nobody is smart enough to figure out the answer to a problem.

It turns out that the history of astrophysics is where we perfected time keeping.

As a scientist, I want to go to Mars and back to asteroids and the Moon because I'm a scientist. But I can tell you, I'm not so naive a scientist to think that the nation might not have geopolitical reasons for going into space.

UV is bad for molecules because its high energy breaks the bonds between a molecule's constituent atoms. That's why UV is bad for you, too: it's always best to avoid things that decompose the molecules of your flesh.

God is an ever receding pocket of scientific ignorance.