Unknown but regular activity found at the black hole at the center of our galaxy

Two Mexican scientists using publicly available data from the Fermi Gamma-ray Telescope discovered activity near the supermassive black hole at the center of our galaxy. The black hole Sagittarius A* at the center of the Milky Way is considered quiet. It does not consume masses of matter around itself, and therefore there are no multiple emissions from its area. However, something flies from it, and scientists have found the probable source of the mysterious flashes.

Image source: AI generation Kandinsky 2.2 / 3DNews

Several years ago, scientists discovered periodic flashes in the X-ray range that came to us from the direction of the black hole Sagittarius A*. Astrophysicists Gustavo Magallanes-Guijón and Sergio Mendoza from the National Autonomous University of Mexico decided to take a closer look at this issue and turned to open data from the Fermi Gamma-ray Orbital Telescope. Scientists analyzed 180 days of telescope recordings from June 22 to December 19, 2022. They reported the results of their analysis to article on the site preprint archive.

Analysis consisted of processing and searching for patterns, especially those that appear periodically. As a result, they found one of them. It turned out that from the vicinity of Sagittarius A* with a reliability of 3 sigma (for an “iron” confirmation of the discovery, a reliability of at least 5σ is required) every 76.32 minutes a gamma signal arrives. There is a high probability that a clump of gas rotates around the black hole in the center of the Milky Way at a distance approximately like Mercury from the Sun at a speed of about 30% of the speed of light.

Scientists believe that the cloud of gas will also emit in other wavelengths, and it is closely related to previously detected periodic flares in the X-ray range. No radiation escapes from the black hole itself, but in the region of absorption of matter in the accretion disk, processes are very, very active and are accompanied by energy emissions. Perhaps in the future Sagittarius A* will still light up, but for now it’s just winking.