“Venus has a runaway greenhouse effect. I kind of want to know what happened there because we're twirling knobs here on Earth without knowing the consequences of it. Mars once had running water. It's bone dry today. Something bad happened there as well.”

American astrophysicist, author, and science communicator

Neil deGrasse Tyson is an American astrophysicist, author, and science communicator. He studied at Harvard University, the University of Texas at Austin, and Columbia University, and has been director of the Hayden Planetarium in New York City since 1996. He was a postdoctoral research associate at Princeton University from 1991 to 1994, then joined the planetarium as a staff scientist and also taught at Princeton as a visiting research scientist and lecturer. At the American Museum of Natural History, he founded the Department of Astrophysics in 1997 and has been a research associate there since 2003.