The Galactic Center: Uncovering the Pulse of our Galaxy

More than a quarter century ago, it was suggested that galaxies such as our own Milky Way may harbor massive, though possibly dormant, central black holes. Definitive proof, for or against, the existence of a massive central black hole lies in the assessment of the distribution of matter in the center of the Galaxy. The motion of the stars in the vicinity of a black hole offers a way to determine this distribution. Based on 15 years of high resolution imaging, the case for a supermassive black hole at the Galactic Center has moved from being a possibility to a certainty. Additionally, spectroscopy has revealed that the stars orbiting in such close proximity are apparently massive and young; the origin of these stars is difficult to explain, given the strong tidal forces, and may provide key insight into the growth of the central black hole.

Speaker: Andrea Ghez, University of California, Los Angeles