Eight super telescopes, many international working groups, and elaborate computer calculations over years led to the first image of the black hole at the center of our Milky Way.
The theoretical physicists led by FIAS Senior Scientist Luciano Rezzolla performed extensive calculations to determine the properties of the plasma being sucked up by the black hole. "We calculated three million synthetic images using different accretion and radiation emission models," Rezzolla says. They also took into account variations caused by different viewing angles of the black hole.
Although the black hole itself is not visible - it is absolutely dark - the gas around it glows in a characteristic way: The image of Sgr A* shows a dark central region, the shadow of the black hole, surrounded by a bright, ring-like pattern. This is the light deflected by the black hole's immense gravity - the black hole has four million times the mass of our Sun.
More telescopes joined together should soon allow more impressive images as well as movies of black holes.
Publication: First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way. Astropysical Journal Letters (2022), DOI: 10.3847/2041-8213/ac6674 https://iopscience.iop.org/article/10.3847/2041-8213/ac6674