“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 of the late 20th and early 21st centuries, he bridges complex cosmic concepts for broad audiences. His work on the Cosmos television series and public lectures makes astronomy accessible, while his writings and media appearances champion evidence-based reasoning and critical thinking.