Not content with being the self-proclaimed “Pluto Killer”, CalTech professor Mike Brown has now co-authored a paper hypothesizing the existence of, in his own words, “the most planet-y of planets” or “Planet 9”, in the far outer reaches of our solar system. We get it: you hate Pluto! But personal planetary battles aside, this is an interesting bit of dynamical detective work in which lead author Konstantin Batygin and Brown argue that a roughly Neptune-sized planet several hundred times further from the Sun than the Earth is needed to explain the peculiar configuration of a dozen or so objects in the Kuiper Belt. Jim Cooney joins Josh and Addie to talk about Planet 9. If it’s the most planet-y of planets, let’s come up with a new name for whatever the Earth is.