The search for our solar system's ninth planet | Mike Brown | Summary and Q&A

Transcript

I'm going to tell you a story from 200 years ago. In 1820, French astronomer Alexis Bouvard almost became the second person in human history to discover a planet. He'd been tracking the position of Uranus across the night sky using old star catalogs, and it didn't quite go around the Sun the way that his predictions said it should. Sometimes it was... Read More