Ask A Spaceman - Ep. 218: How Do We Know What the Milky Way Looks Like?

Why is it so hard to get a picture of the Milky Way? How much of our galaxy have we mapped? What the heck is a “barred spiral” and what does that have to do with our core? I discuss these questions and more in today’s Ask a Spaceman!   This episode is sponsored by BetterHelp. Give online therapy a try at betterhelp.com/spaceman and get on your way to being your best self. Visit BetterHelp to get 10% off your first month!   Support the show: http://www.patreon.com/pmsutter All episodes: http://www.AskASpaceman.com Follow on Twitter: http://www.twitter.com/PaulMattSutter Read a book: http://www.pmsutter/book   Keep those questions about space, science, astronomy, astrophysics, physics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE!   Big thanks to my top Patreon supporters this month: Justin G, Chris L, Barbara K, Alberto M, Duncan M, Corey D, Naila, John S, Joshua, Scott M, Rob H, Louis M, John W, Alexis, Erin J, Gilbert M, Valerie H, Tim R, Mark R, Alan B, Craig B, Mark F, Richard K, Maureen R, Stace J, Stephen S, Stephen J, Joe R, David P, robert b, Sean M, Tracy F, Sarah K, Ryan L, Ella F, Sarah K, Richard S, Sam R, Thomas K, James C, Syamkumar M, Homer v, Mark D, Bruce A, Steven M, Bill E, Tim Z, Linda C, Aissa F, Marc H, Scott M, Avery P, Farshad A, Michael W, Kenneth D, Gary K, Paul G, David W, dhr18, Ron D, Lode S, Alyssa K, Roger, Bob C, Simon G, Red B, Stephen A, James R, Robert O, Lynn D, Allen E, Michael S, Jordan, Reinaldo A, Jessica M, Patrick M, Amy Z, Sheryl, John G, David W, Jonathan S, Sue T, Josephine K, Chris, Jules R, P. S, Michael S, Erlend A, and James D!   Thanks to Cathy Rinella for editing.  Hosted by Paul M. Sutter.   We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs.  Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too!  Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations.  Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at [email protected].