Cosmology Today

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Cosmology Today. Cosmic Answers, Cosmic Questions. The universe is flat, 13.7billion years old , and it is composition is as follows:. What is dark matter? What is dark energy? What caused inflation? Why is there an excess of matter over antimatter. The Expanding Universe. Modern Cosmology. - PowerPoint PPT Presentation

Text of Cosmology Today

  • Cosmology Today

    Astrophysics Lecture 3

  • Cosmic Answers, Cosmic QuestionsWhat is dark matter?What is dark energy?What caused inflation?Why is there an excess of matter over antimatterThe universe is flat, 13.7billion years old , and it is composition is as follows:

    Astrophysics Lecture 3

  • The Expanding UniverseSlides based on material by Joe Mohr, Wayne Hu, Rocky Kolb and other web sites.

    Modern Cosmology

    Astrophysics Lecture 3

  • Outline1. IntroductionFrom the Earth to the Universe108,1013,1022,1026mStandard Candles and Hubble Law

    2. Modern ObservationsMeasuring recession velocities Nature of light and emissionDoppler effectGalaxy spectroscopyEstimating large distancesStandard candles and rodsSupernovae as standard candlesResults from Type Ia supernovae4. Summary3. InterpretationThe bad neighbor hypothesisHomogeneous expansion

    Astrophysics Lecture 3

  • NASA Image of Planet Earth104 kmDensity 5000kg/m3

    A high density anomoly

    Average density ofuniverse 10-27 kg/m3

    Astrophysics Lecture 3

  • Our Place in the Solar SystemNine planets.SUN- average low mass star, ~109m diam, 1030kgEarth orbital radius: 1011m( the only place in the universe where we know there is life.)Pluto orbit: 1013mOort Cloud: 1014m, 1011 objects

    Astrophysics Lecture 3

  • M31, the Andromeda Galaxy If this picture were of the Milky Way, our solar system would lie here.Our solar systemlies within theMilky Way, a gal-axy much like M31.

    Nstars~1012.M~1043kgRad~10kpc=30klyDensity~10-17kg/m3Distance~1Mpc

    Telescopes are time machines!The further we look, the further we see into the past

    Astrophysics Lecture 3

  • Deep Hubble Space Telescope ImageA younger part ofthe universe.A deep image of an emptyportion of the sky with theHubble Space Telescopereveals that the universe isfilled with galaxies- many justlike our own. The lightwe see from the most distantgalaxies has traveled approx-imately 10 billion years to reach us.

    ~few 1000 galaxiesdensity~10-27kg/m3

    Astrophysics Lecture 3