In this episode we explore the possibility that a ninth planet lurks along the outskirts of our solar system. Could it be a Small Neptune? A Super Earth? Or just Fake News. We discuss some of the history of successful and failed hypothesized planets, the structure of the outer solar system, likely properties of a putative planet nine, how it could be detected, and how it might have formed.

Timestamps:

1. 00:32 - Welcome