Princeton University Gravity Initiative Seminar Series

Abstract: In 2022, the Event Horizon Telescope collaboration revealed the first images of the shadow of our Milky Way supermassive black hole, Sagittarius A* (Sgr A*). Since its detection in the mid-70s, this bright radio source in the Galactic center has been shrouded in a veil of mystery. The Nobel-awarded stellar orbits research in the Galactic center pinned down its mass and distance, showing evidence of an extremely compact 4 million-solar-mass object at the heart of our Galaxy. The EHT then provided the first direct evidence that this object is indeed a black hole and resolved its shadow for the first time. In this talk, I will explain the challenges of imaging Sgr A* and how these were overcome by the EHT to obtain its latest results. In the next decade, the EHT will have the capability to make detailed high-dynamic range millimeter and sub-millimeter polarimetric movies of M87, Sagittarius A*, and other black hole targets – tracing the dynamical processes underlying black hole accretion and jet launching while zooming in on stationary horizon-scale features that reveal the imprint of black hole spin.