The Monster at the Heart of our Galaxy

Learn about new developments in the study of black holes. Through the capture and analysis of twenty years of high-resolution imaging, Dr. Andrea Ghez and her team have moved the case for a supermassive black hole at the center of our galaxy from a possibility to a certainty. This shift was made possible with the first measurements of stellar orbits around a galactic nucleus. Further advances in state-of-the-art high-resolution imaging technology on the world’s largest telescopes have greatly expanded the power of using stellar orbits to study black holes. Recent observations have revealed an environment around the black hole that is quite unexpected (young stars where there should be none; a lack of old stars where there should be many; and a puzzling new class of objects). Continued measurements of the motions of stars have solved many of the puzzles posed by these perplexing populations of stars. This work is providing insight into how black holes grow and the role that they play in regulating the growth of their host galaxies. Future measurements of stellar orbits at the center of the Milky Way hold the promise of improving our understanding of gravity through tests of Einstein’s theory of general relativity in an unexplored regime.