What is the largest galaxy? For a long time, the largest has been IC 1101, around 4 million light years in diameter. But in recent weeks, there has been talk of a new, even larger galaxy, Alcyoneus, which is said to be more than 16 million light years in diameter! But is that what's really being proposed in the original paper detailing the discovery? Not exactly, because Alcyoneus is a Radio Galaxy. But what is a radio galaxy, and if Alcyoneus is not the largest galaxy, then how large really is it? Do you use these videos to sleep or for night time watching? Check out the new sleeping space playlist, a collection of my most chilled out and ambient videos. https://youtube.com/playlist?list=PLkoaIad9k4NIlsG6g-almaZH6MzR_T5eV I don't have a Patreon, but if you would like to support the channel you can become a SeaSquad Member. Members gain access to exclusive badges, emojis, and early video previews! Join with the link below: https://www.youtube.com/sea_Media/join Join the official #SeaSquad Discord Server: https://discord.gg/GhbzV4kKee (NON-ENGLISH VIEWERS) To get subtitles in another language, click the [CC] button in the bottom right corner of the screen, then click the Settings (cogwheel) icon next to it, click "Subtitles / CC" and click "Auto-Translate", and select your language from there. SOUNDTRACK: All tracks by CO.AG Music: https://www.youtube.com/channel/UCcavSftXHgxLBWwLDm_bNvA - Sound of the Sun: https://youtu.be/4u6Gt7NXlDE - A World of Different Dimensions: https://youtu.be/g9vULHb_7mQ - Your Outer World: https://youtu.be/OnZjKSQS9b0 - Travel Beyond Your Imagination: https://youtu.be/Z2XDR9N00Jo - Create the Future: https://youtu.be/z9HM9VTnFDQ FOOTAGE: The space scenes in this video were captured using SpaceEngine Pro, a virtual universe simulator: http://spaceengine.org/ Get SpaceEngine on Steam: https://store.steampowered.com/app/314650/SpaceEngine/ Stock Footage Sources: - Videezy.com - Pexels.com - Videvo.net ( https://www.videvo.net/video/moving-radio-telescope-time-lapse/5148/ ) SOURCES OF INFORMATION: - Original Paper on Alcyoneus by Martijn Oei et al.: https://arxiv.org/abs/2202.05427 - Article Detailing the Discovery: https://phys.org/news/2022-02-giant-radio-galaxy.html - Synchrotron Radiation: https://www.nist.gov/pml/sensor-science/what-synchrotron-radiation - Radio Galaxies: https://www.britannica.com/science/Seyfert-galaxy - Giant Radio Galaxies: https://astronomycommunity.nature.com/posts/giant-radio-galaxies-the-cosmic-behemoths Business Enquiries: SEA.Enquiries@gmail.com (I don't do paid promotions, sorry) CHAPTERS: 0:00 What is the Largest Galaxy? 2:02 Galaxies 4:13 IC 1101 6:32 Radio Galaxies 12:31 Giant Radio Galaxies 14:40 Alcyoneus, Largest Radio Galaxy 18:39 Alcyoneus' Host Galaxy 22:57 The Largest Galaxy- Some Considerations 28:51 Closing Statements ... https://www.youtube.com/watch?v=ph7nW16sseo

How did Earth get its moon? Why is Mercury so close to the sun? Why does Uranus orbit on its side? And what makes Pluto unique among the other worlds? The answers to all of these questions are the many collisions that ravaged the early Solar System. Each of our neighbouring worlds bears scars which echo their violent past, from the many craters of the moon's battered surface, to the sideways rings of the planet Uranus. And in this video, we will examine a number of the most significant collisions, which each played a pivotal role in building up the Solar System as we know it today. Last time out, we talked about the history of Earth, but with one key detail missing- the formation of the Moon. And so perhaps that would be a good place for us to start, as we revisit the many collisions of the early Solar System. If you like this channel, can support it on Patreon. Patrons get ad-free access to videos, and also get early access sneak peaks! https://www.patreon.com/sea_media Using these videos to drift off? Check out the sleeping space playlist, a collection of my chilled out ambient videos: https://youtube.com/playlist?list=PLkoaIad9k4NIlsG6g-almaZH6MzR_T5eV SOUNDTRACK: - Deepest Woods | Enzo Orifice (Storyblocks) - The Ghost of Aberbeeg | CO.AG Music - Edge of Silence, Ambient Sounds 06 | CO.AG Music - Balefire | Scott Buckley Creative Commons Music - Ambient Glass Drama Documentary Music | Music Media Company (Storyblocks) - Short Song 011023 | Chris Zabriskie Creative Commons Music - Short Song 020823 | Chris Zabriskie Creative Commons Music - Dreams | Humans Win (Storyblocks) - Not Saying Enough | Michael Vignola (Storyblocks) - Speak to Me | CO.AG Music - A Dark, Silent Night | Humans Win (Storyblocks) CO.AG Music: https://www.youtube.com/@co.agmusic1823 Scott Buckley Music: https://www.scottbuckley.com.au Chris Zabriskie Music: https://chriszabriskie.bandcamp.com All music by Scott Buckley and Chris Zabriskie is licensed under Creative Commons 4.0 Reuse guidelines. FOOTAGE: The space scenes in this video were captured using SpaceEngine Pro, a virtual universe simulator: http://spaceengine.org/ Other sequences were made using Universe Sandbox: https://universesandbox.com Other space images and sequences are public domain resources provided by NASA and the ESA NASA: https://www.nasa.gov ESA: https://www.esa.int Stock footage sequences were provided by Storyblocks: https://www.storyblocks.com Other sequences were provided by Vecteezy.com: https://www.vecteezy.com Other videos, simulations and visual resources that appear in this video: - BBC Planets Footage of Mercury: https://youtu.be/XhKAxwfNW_c?si=lOuWPd0r4i3mQfyG - Andreas Reufer & Erik Asphaug Simulation of Mercury Hit and Run: https://vimeo.com/77504026 - NCCR PlanetS Mercury Collision Simulation: https://youtu.be/14HgkrIa36Q?si=_XhYYsstDDIR45zu - Pavel Ševeček Simulation of Embryos: https://youtu.be/xj443uAAGA8?si=_9rsjLFlZV8N-JGY - Pavel Sevecek Simulation of Giant Impact: https://youtu.be/R9Nx_39Xoco?si=zx127oJKAwo_wlgX - Mercury Demolition Derby: https://youtu.be/BaH15a44e8A?si=8EPfpf85dvciR0cF - Pretpark Reizen Teacups Ride Footage: https://youtu.be/OjWIiYAW7TY?si=cnIJNja9xNS4cKzu - Pluto-like Ice-world Collisions: https://youtu.be/DaYWDvrhL68?si=iRFRxPYh8WwHA9Ny - IAU Voting and General Assembly: https://youtu.be/0Eyi47O5Iyg?si=Xlye8WF0zaBhlEzJ SOURCES OF INFORMATION: This video assumes the contemporary scientific explanations of the established Nebular Hypothesis Model of the Solar System's formation. - Giant Impact Hypothesis: https://arxiv.org/abs/1603.04536 - Rare Mercury Mystery: https://arxiv.org/abs/1808.02448 - Mercury Didn't Form via a Single Impact: https://arxiv.org/abs/2207.14774 - Simulating Uranus' Collision: https://www.nasa.gov/feature/ames/planet-shifting-collision-shaped-uranus-rolling-rotation - Formation of Pluto's Four Moons: https://skyandtelescope.org/astronomy-news/how-did-plutos-moons-form/ - Pluto's Wandering Heart: https://skyandtelescope.org/astronomy-news/sputnik-planitia-drives-plutos-wandering-heart/ - Pluto's Underground Ocean: https://svs.gsfc.nasa.gov/13000 - 10 Things We Learned About Pluto from New Horizons: https://pluto.jhuapl.edu/News-Center/News-Article.php?page=20200714 CHAPTERS 0:00 Introduction 1:37 The Terrestrial Planets 3:33 Collision that Formed the Moon 6:07 Giant Impact Hypothesis 9:42 What Happened to Mercury? 13:37 Late Heavy Bombardment 16:45 What Rammed into Uranus? 20:32 The Dwarf Planet 23:43 Pluto & Charon's Moons 27:25 Sputnik Planitia 32:58 Closing planetary collisions, the collision that formed the moon, theia impact, mercury collision, Uranus super earth collision, Pluto collision, dwarf planet collision, Pluto charon collision, Sputnik Planitia collision, impact that tipped Uranus, Kuiper belt collision ... https://www.youtube.com/watch?v=5cw0dO5RF-8