Black Hole Size Revealed by Its Eating Pattern

An artist’s impression of an accretion disk rotating around an unseen supermassive black hole.

An artist’s impression of an accretion disk rotating around an unseen supermassive black hole. The accretion process produces random fluctuations in luminosity from the disk over time, a pattern found to be related to the mass of the black hole in a new study led by University of Illinois Urbana-Champaign researchers. (Image: Mark A. Garlick / Simons Foundation)