Understanding the First Images of a Black Hole

Black holes are believed to sit at the center—the nucleus—of nearly every galaxy in the universe, including our own Milky Way. Nuclear black holes draw in gas—accrete—from their surroundings that heats up and becomes luminous, producing radiation that spans the electromagnetic spectrum. Professor Gammie’s research group is a world leader in using computer models to take ideas about how black holes accrete and translate them into predictions for what telescopes on Earth and in orbit around the Earth will see. His group is especially focused on results from an experiment called the Event Horizon Telescope (EHT); Professor Gammie co-leads the theory working group within the EHT collaboration. EHT operates by combining signals from millimeter wavelength telescopes around the globe to produce very high angular resolution images of astronomical sources, especially black holes. EHT released the first spatially resolved image of a black holein April 2019 and is expected to steadily release better understood and higher quality images thereafter.