Imaging the Unseen: Taking the First Picture of a Black Hole

Tuesday, October 15, 2019 - 9:50am - 10:35am
Keller 3-180
Katie Bouman (California Institute of Technology)
This talk will present the methods and procedures used to produce the first image of a black hole from the computational Event Horizon Telescope. It has been theorized for decades that a black hole will leave a shadow on a background of hot gas. Taking a picture of this black hole shadow could help to address a number of important scientific questions, both on the nature of black holes and the validity of general relativity. Unfortunately, due to its small size, traditional imaging approaches require an Earth-sized radio telescope. In this talk, I discuss techniques we have developed to photograph a black hole using the Event Horizon Telescope, a network of telescopes scattered across the globe. Imaging a black hole’s structure with this computational telescope required us to reconstruct images from sparse measurements, heavily corrupted by atmospheric error. The resulting image is the distilled product of an observation campaign that collected approximately five petabytes of data over four evenings in 2017. I will also discuss future instrumental and algorithmic directions for better imaging and understanding of black holes.