Swirls of infalling gas heat up and give off radiation to illuminate a black hole's vicinity, and the orbits of stars around a black hole allow astronomers to estimate its mass. (scientificamerican.com)
Analysis of gigantic structures known as Fermi Bubbles has revealed that the supermassive black hole consumed a large clump of infalling gas roughly 6 million years ago. (ibtimes.com)
Protostars produce emission by converting the gravitational energy of infalling material to the thermal energy. (alma-telescope.jp)