• Size and recipe
• Black holes from afar, near, and inside
• Black hole inspiral and collisions

Evidence for Black Holes

• X-ray binaries: Cygnus X-1
• Milky Way center:
  • Radio overview
  • The power of adaptive optics
  • Stellar orbits: Munich group, UCLA group
  • possibly related: gamma-ray bubbles
• other galaxies
  • active galaxies: M87; AGN gallery
  • quasar and host galaxies
  • supermassive black holes
  • black holes and galaxies somehow know about each other
  • an important clue? a binary supermassive black hole pair!
• Gravitational radiation
  Hulse & Taylor's award-winning binary pulsar
  gravity-wave observatories: LIGO (operational) and LISA (future)