799: Navigation in Space, Sizes of Black Holes and Planet 9 | Q&A 178

In this week's live Questions and Answers show, I explain how big black holes are, what coordinate system astronomers use to map objects in the sky, and what could have collapsed clouds of hydrogen to form the first stars? 00:00 Start 00:42 How big are black holes? 03:15 What coordinate system do astronomers use to map objects in space? 06:50 What created the first stars? 08:19 If Planet 9 is a black hole, how could we detect it? 10:10 How do gamma rays escape the gravity of a black hole? 11:04 Any alternative theories to the Big Bang that I find convincing? 14:51 Where is Starman right now? 15:44 How do we know the shape of the Milky Way? 18:50 How far is James Webb in light-seconds? 19:45 Are filaments and dark matter related? 21:24 How do orbits become and stay stable? 24:11 How dangerous is the Universe to life? 27:39 What do I think of the Dark Forest theory? 29:25 Are rubble pile asteroids dead comets? 30:52 Are some galaxies more habitable? 32:03 Could a Dyson Sphere stay inflated by the Solar Wind? Want to be part of the questions show? Ask a short question on any video on my channel. I gather a bunch up each week and answer them here. 🚀 OUR WEBSITE: ════════════════════════════════════ https://www.universetoday.com/ 🚀 PODCAST LINKS: ════════════════════════════════════ RSS: https://universetoday.com/audio iTunes: https://universetoday.com/itunes Spotify: https://universetoday.com/spotify 🚀 EMAIL NEWSLETTER: ════════════════════════════════════ Read by 50,000 people every Friday. Written by Fraser. No ads. Subscribe Free: https://universetoday.com/newsletter 🚀 OTHER PODCASTS: ════════════════════════════════════ Weekly Space Hangout: Weekly news roundup with Fraser, special guests, and other space journalists. RSS: https://www.universetoday.com/feed/wshaudio/ iTunes: https://podcasts.apple.com/ca/podcast/weekly-space-hangout-audio/id836926769 YouTube: https://www.youtube.com/channel/UC0-KklSGlCiJDwOPdR2EUcg/ Astronomy Cast: Award-winning, long-running deep dive into space and astronomy with Fraser and Dr. Pamela Gay. RSS: https://astronomycast.libsyn.com/rss/ iTunes: https://podcasts.apple.com/ca/podcast/astronomy-cast/id191636169?mt=2 YouTube: https://www.youtube.com/channel/UCUHI67dh9jEO2rvK--MdCSg 🚀 JOIN OUR COMMUNITY: ════════════════════════════════════ Patreon: https://patreon.com/universetoday 🚀 OTHER SOCIAL MEDIA: ════════════════════════════════════ Twitter: https://twitter.com/fcain Twitter: https://twitter.com/universetoday Facebook: https://facebook.com/universetoday Instagram: https://instagram.com/universetoday Twitch: https://twitch.tv/fcain 🚀 CONTACT FRASER: ════════════════════════════════════ Email: frasercain@gmail.com 🚀 LICENSE: ════════════════════════════════════ Creative Commons Attribution 4.0 International (CC BY 4.0) You are free to use my work for any purpose you like, just mention me as the source and link back to this video.