A Universe of Galaxies

A Universe of Galaxies - AUniverseofGalaxies movesawayfromus

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DIFFRACTION A Universe of Galaxies 17:02 Each galaxy= 100 billion stars -moves away from us the farther, the faster Hobbel - discovered expanding universe Ex. Raisin bread Expansion started 13.7 billions years ago (when everything was jammed together in one place) o really hot/dense Now cooled off, continues to cool with more expansion  Telescopes as Time Machines Light travel= Look back time The most Distant Galaxies and Quasars: 13 billion light years away o Light took 13 billion years to reach us What is the Universe made of? Normal matter Dark Matter- interacts via gravity, but not with light Gravitational lensing”  shows that 85% of all matter is  dark matter What is it? Nobody knows. Gravity should slow expansion rate. BUT it is measured to be speeding up. ???
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Because of DARK ENERGY 4% Normal matter (the only part we see) 23% Dark matter
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A Universe of Galaxies - AUniverseofGalaxies movesawayfromus

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