Island Universes: Discovering Galaxies Beyond the Milky Way - Chris Lintott

00:00 // Introduction: The Vast Universe 00:08 // The Universe is Really, Really Big 00:24 // Our Place in the Universe 01:06 // The Scale of the Observable Universe 02:13 // The Mind-Boggling Number of Stars 03:42 // Feeling Lost in the Cosmos 05:23 // Searching for Familiar Places in the Universe 06:57 // Earth-Like Planets and Strange Worlds 08:46 // The Nature of Jupiter and Other Planets 10:29 // How We Measure the Universe 12:14 // Understanding Star Distances and Parallax 14:40 // Mapping the Milky Way Galaxy 17:27 // The Great Debate: Are There Other Galaxies? 19:50 // Discovering Spiral Galaxies 22:06 // Confirming the Existence of Other Galaxies 24:35 // The Large-Scale Structure of the Universe 26:52 // Mapping the Universe in 3D 28:40 // The Cosmic Web: A Universe of Structures 29:53 // Conclusion: The Infinite Wonders of the Cosmos The discovery that we live in an ordinary galaxy, one of several hundred billion in the observable Universe, instigated a profound change in thinking about our place in the Universe. This first lecture covers the Great Debate of the early twentieth century as new telescopes and new ways of observing the cosmos put our Milky Way in its place; and looks at how subsequent observations helped us understand how galaxies like our own formed and evolved. This lecture was recorded by Professor Chris Lintott on 13 September 2023 at Barnard's Inn Hall, London Chris is Gresham Professor of Astronomy. He is also a Professor of Astrophysics at the University of Oxford, and a Research Fellow at New College. https://www.gresham.ac.uk/speakers/professor-chris-lintott The transcript and downloadable versions of the lecture are available from the Gresham College website: https://www.gresham.ac.uk/watch-now/galaxies-beyond Gresham College has offered free public lectures for over 400 years, thanks to the generosity of our supporters. There are currently over 2,500 lectures free to access. We believe that everyone should have the opportunity to learn from some of the greatest minds. To support Gresham's mission, please consider making a donation: https://gresham.ac.uk/support/ Website: https://gresham.ac.uk Twitter: https://twitter.com/greshamcollege Facebook: https://facebook.com/greshamcollege Instagram: https://instagram.com/greshamcollege