NORMAL GALAXIES

  • Observing galaxies - night sky brightness
  • Most of a galaxy is fainter than night sky
  • Low surface brightness galaxies
  • M101, prototypical high surface brightness spiral
  • Malin I, large low surface brightness disk galaxy
  • Malin I luminosity distribution
  • How many galaxies are we missing?

  • Physical properties vs Hubble type
  • Size and mass
  • Color
  • Gas content

  • Classify galaxies in the Hubble Deep Field

  • Hubble deep field wide view
  • Hubble deep field details

    Dark Matter in Galaxies:

  • Dark matter in galaxies
  • Distribution of mass via rotation curves
  • Milky Way rotation curve
  • Some well-observed rotation curves
  • NGC 3198 -- HI extends much further than stars
  • Mass inside R as function of circular velocity
  • Flat rotation curves -- huh?
  • How do we go from L to M?
  • We postulate existence of dark matter
  • Dark matter candidates
  • Wait a minute!