“Pluto's orbit is so elongated that it crosses the orbit of another planet. Now that's... you've got no business doing that if you want to call yourself a planet. Come on, now! There's something especially transgressive about that.”

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.