What happens when two black holes' event horizons overlap? Neil deGrasse Tyson and co-host Chuck Nice answer fan questions about the north side of the magnet, the internal structure of other planets, dark matter, and more. Kicking things off with a question about mapping the universe using gravitational waves, Neil explains how LIGO helped detect them and how pulsars might one day let us track their movement across space. Chuck gives us a taste of his best impressions—galactic gumbo and a budget-cutting politician—as the discussion shifts to NASA’s funding and the surprising truth about how little of the federal budget goes to space exploration. What if the universe is a four-dimensional sphere? Neil breaks down the geometry of our cosmos and why a closed universe would look a lot different. Then we discuss the concept of higher dimensions: could our universe be falling into another like a cosmic waterfall? We explore if matter ever touches and what role does dark matter play in gravitational interactions. We explore whether we ever truly touch anything, why dark matter doesn't clump into planets, how we understand the interiors of other worlds, and what happens when black holes collide. Neil and Chuck tackle magnet poles, planetary spins, and whether the universe is hiding life beyond Earth. Finally, Neil explores why the James Webb Space Telescope is rewriting our understanding of the early universe and shares what he thinks the biggest breakthrough in astrophysics will be in the next 50 years. Thanks to our Patrons Allison Carlin, Brad Hostetter, Nick, Paul Sinnema, Andre Stone, John Brooks, Larry Martin, Vivek kolla, Alfredo Gomez, Brett Johnson, Steffan Steff, Ori Harush, Megan Moss Freeman, Kyle Rhone, Kevin O'Reilly, Morgan Derischebourg, Gannon Escobar, Tim Smallidge, Berk Akay, Stephen Ferguson, Laura Nicole Deschaine, Incommunicado, Erik Wislinsky, Ken Goldberg, Shawn Noah, Micheal Klein, Aiden James, Lisa Hansen, Gabriel Siqueira, Mike Moss, Mohammed Elmredi, Jonathan eve, Conrad Koopman, Nishe Noeth, Bipin Raj Bista, Cameron Berg, Stuart Holmes, Daniel, Dalton Lasner, Darren Mieskoski, Erik Chavez, Mark Whitt, Clamettis Wright, John King, Margaret De Foe, Raymond Foust, TrekDiva, Brandon Wheeler, Lisa Bayans, and Amanda for supporting us this week. Timestamps: 00:00 - Introduction: Grab Bag 01:44 - Could We Map the Whole Universe? 08:30 - Is the Universe a 4D Sphere? 11:38 - 3D Objects in a 2D World 18:04 - Do We Ever Touch Anything? 21:14 - Mercury’s Core 27:53 - Modelling When Black Holes Collide 33:14 - North Pole of the Magnet 38:03 - Breakthroughs in Astrophysics 38:55 - JWST Best Unexpected Discovery Check out our second channel, @StarTalkPlus Get the NEW StarTalk book, 'To Infinity and Beyond: A Journey of Cosmic Discovery' on Amazon: https://amzn.to/3PL0NFn Support us on Patreon: https://www.patreon.com/startalkradio FOLLOW or SUBSCRIBE to StarTalk: Twitter: http://twitter.com/startalkradio Facebook: https://www.facebook.com/StarTalk Instagram: https://www.instagram.com/startalk About StarTalk: Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up! #StarTalk #NeildeGrasseTyson