If you get asteroids about a kilometer in size, those are large enough and carry enough energy into our system to disrupt transportation, communication, the food chains, and that can be a really bad day on Earth.

Creativity is seeing what everyone else sees, but then thinking a new thought that has never been thought before and expressing it somehow. It could be with art, a sculpture, music or even in science. The difference, however, between scientific creativity and any other kind of creativity, is that no matter how long you wait, no one else will ever compose "Beethoven's Ninth Symphony" except for Beethoven. No matter what you do, no one else will paint Van Gogh's "Starry Night." Only Van Gogh could do that because it came from his creativity.

I never got into 'Star Wars.' Maybe because they made no attempt to portray real physics. At all.

To achieve this density of a neutron star at home, just cram a herd of 50 million elephants into the volume of a thimble.

It's my duty to enlighten people.

No matter what eyewitness testimony is in the court of law, it is the lowest form of evidence in the court of science.

Great scientific minds, from Claudius Ptolemy of the second century to Isaac Newton of the seventeenth, invested their formidable intellects in attempts to deduce the nature of the universe from the statements and philosophies contained in religious writings.... Had any of these efforts worked, science and religion today might be one and the same. But they are not.