The supermassive black hole at the center of our Milky Way galaxy, Sagittarius A*, is by far the closest such object to us, about 27,000 light-years away. Although it is not nearly so active or luminous as other galactic nuclei with supermassive black holes, its relative proximity makes it appear much brighter to us than other similar sources and provides astronomers with a unique opportunity to probe what happens when gas clouds or other objects get close to the "edge" of a black hole.