The Big Bang, Cosmology part 1: Crash Course Astronomy #42

Thanks to observations of galaxy redshifts, we can tell that the universe is EXPANDING! Knowing that the universe is expanding and how quickly its expanding also allows us to run the clock backwards 14 billion years to the way the universe began - with a bang. Crash Course Astronomy Poster: http://store.dftba.com/products/crashcourse-astronomy-poster -- Table of Contents Distant Galaxies Show a Red Shift in Their Spectra 2:07 The Universe is Expanding 2:51 This Model is Called “The Big Bang” 5:12 The Universe is Almost 14 Billion Years Old 11:43 -- PBS Digital Studios: http://youtube.com/pbsdigitalstudios Follow Phil on Twitter: https://twitter.com/badastronomer Want to find Crash Course elsewhere on the internet? Facebook - http://www.facebook.com/YouTubeCrashCourse Twitter - http://www.twitter.com/TheCrashCourse Tumblr - http://thecrashcourse.tumblr.com Support CrashCourse on Patreon: http://www.patreon.com/crashcourse -- PHOTOS/VIDEOS Hubble Goes to the eXtreme to Assemble Farthest-Ever View of the Universe http://www.nasa.gov/mission_pages/hubble/science/xdf.html [credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team] Out of this whirl: The Whirlpool Galaxy (M51) and companion galaxy http://www.spacetelescope.org/images/heic0506a/ [credit: NASA, ESA, S. Beckwith (STScI), and The Hubble Heritage Team STScI/AURA)] Red-Shifts in the Spectra of Extra-glactic Nebuale http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1936ApJ....83...10H [credit: American Astronomical Society, NASA Astrophysics Data System] Andromeda http://www.nasa.gov/images/content/386910main_M31_optical_wide.jpg [credit: Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF] The Big Bang (video) http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=10128 [credit: NASA] The Sun https://www.nasa.gov/sites/default/files/706436main_20121114-304-193blend_m6-orig_full.jpg [credit: NASA/SDO] Alpha Centauri http://www.eso.org/public/images/eso1241e/ [credit: ESO/Digitized Sky Survey 2, Acknowledgement: Davide De Martin] Andromeda https://en.wikipedia.org/wiki/Andromeda_Galaxy#/media/File:Andromeda_galaxy_2.jpg [credit: NASA/JPL-Caltech] Friedmann Universes https://commons.wikimedia.org/wiki/File:Friedmann_universes.svg Friedmann Equation http://burro.astr.cwru.edu/Academics/Astr328/Notes/Expansion/friedmann.html Penzias and Wilson stand at the 15 meter Holmdel Horn Antenna that brought their most notable discovery. https://en.wikipedia.org/wiki/Arno_Allan_Penzias#/media/File:Horn_Antenna-in_Holmdel,_New_Jersey.jpeg [credit: NASA] Planck CMB http://www.esa.int/spaceinimages/Images/2013/03/Planck_CMB [credit: ESA and the Planck Collaboration] Galaxy Superclusters http://irfu.cea.fr/Projets/coast_documents/images_MareNostrum/SDvision-MN00097-hires-01-mymix-a0_075.jpg [credit: Marenostrum Numerical Cosmology Project]