Black Holes and Gravitational Lensing

We end our week's discussion of black holes by looking at one of the ways we can "see" black holes - Gravitational lensing. This is the process where a black hole bends light around itself (light that doesn't get caught in the event horizon, of course!) the same way a lens bends light to form an image. When the earth, a black hole, and a galaxy are lined up just right, we can see amazingly distorted images that help us figure out where a black hole is and how strong its gravitational force is!