"Let's find a new way to think about the entire taxonomy of solar system objects, and not clutch to this concept of 'planet,' which, of course, only ever meant, 'Do you move against the background stars, regardless of what you're made of?'"
American astrophysicist and science communicator. He serves as director of the Hayden Planetarium in New York and has hosted and produced science programming and media. He is widely known for public education work in astronomy.