The Milky Way Galaxy has a black hole at its heart -- an object called Sagittarius A* (pronounced A-star). We can’t see it visually, but radio astronomers can easily spot it. A group led by Dr. Shep Doeleman at MIT’s Haystack Observatory made a startling measurement of the accretion disk around Sagittarius A*. In this edition of Astronomy Behind the Headlines we talked with Dr. Doeleman about his team’s discovery.