Viewing the Shadow of the Black Hole at the Galactic Center.

  title={Viewing the Shadow of the Black Hole at the Galactic Center.},
  author={Heino Falcke and Fulvio Melia and Eric Agol},
  journal={The Astrophysical Journal},
In recent years, evidence for the existence of an ultracompact concentration of dark mass associated with the radio source Sagittarius A* in the Galactic center has become very strong. However, unambiguous proof that this object is indeed a black hole is still lacking. A defining characteristic of a black hole is the event horizon. To a distant observer, the event horizon casts a relatively large "shadow" with an apparent diameter of ~10 gravitational radii that is due to the bending of light… Expand
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