“We are made out of stardust. The iron in the hemoglobin molecules in the blood in your right hand came from a star that blew up 8 billion years ago. The iron in your left hand came from another star. We are the laws of chemistry and physics as they have played out here on Earth and we are now learning that planets are as common as stars. Most stars, as it turns out now, will have planets.”

On an error in the movie Contact, which was based on her life:

“It’s just before the first kiss, so Jodie Foster is out on the balcony behind the control room and they’re looking at the stars and the beautiful telescope and she’s doing, ‘Oh, look at all of those stars. If only one in a million of those stars had planets, and only one in a million of those planets had life, and if only one in a million of those lifeforms were transmitting, there would be millions of signals for us to detect.’ The math is all wrong. It’s really annoying. There are 100 billion stars in the Milky Way galaxy. And even if she was looking up and seeing them all, which she wasn’t, she’s multiplying 1011 * 10-18 and coming up with 106. That’s wrong by 13 orders of magnitude. And the really sad story is that Carl Sagan died while this movie was being edited. And there was a memorial service for Carl in the spring. And [someone] wanted to show the assembled scientists and engineers a clip from the film. … So [the kiss clip] is the clip that’s shown, and you hear this gasp at the end from all the scientists and engineers who can obviously do the math and know it’s wrong.”