AaS! 125: Does Planet Nine Exist?

Why do we think the solar system might have another planet? Why do we think it doesn't? How do test for something that's too far away to see? I discuss these questions and more in today's Ask a Spaceman!

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Big thanks to my top Patreon supporters this month: Matthew K, Justin Z, Justin G, Kevin O, Duncan M, Corey D, Barbara K, Neuterdude, Chris C, Robert M, Nate H, Andrew F, Chris L, Jon, Cameron L, Nalia, Aaron S, Kirk T, Dr. Johnny Fever, Tim R, Joe R, Neil P, Bryan D, Irene P, Dustin R, Matt C, Iothian53, Steve P, Debra S, Ken L, Alberto M, Ron W, Chris L, Mark R, Alan B, Stephen J, David P, John F, Maureen R, Frank T, Craig B, Jesse A, Steven L, Ulfert B, Dave L, Stace J, S Stark, Richard K, Carol S, Stephen M, Grace M, Jeremy K, Russell W, David B, Tamara F, Robert B, Fr Bruce W, Catherine R, Nicolai B, Sean M, Nate H, Edward K, Ped, Chuck C, Jose Pablo V, Stephen S, Elizabeth W, Eric F, Tracy F, Roger G, Callan R, Nils M, John W, George, Tom G, Monika, Michael H, Tom, Sarah K, Robert S, and Gerald!

Music by Jason Grady and Nick Bain. Thanks to Cathy Rinella for editing.

Hosted by Paul M. Sutter, astrophysicist and the one and only Agent to the Stars (http://www.pmsutter.com).