Having analyzed data gathered by the Fermi Gamma-Ray Space Telescope between June and December last year, researchers have concluded that a flare of gamma radiation is emitted every 76 minutes or so from that area.
These gamma rays supposedly originate from a blob of gas that is spinning around the black hole in question, Sagittarius A*, at very high speed (approximately one third of the speed of light).
The researchers also noticed an apparent relation between these gamma ray bursts and the periodic emissions of X-rays from the same area, with the periodicity of the latter being about twice the periodicity of the former.
"The coincidence of the multiwavelength periodicity in X-ray and gamma-ray points towards a single physical mechanism that produces it," scientists Gustavo Magallanes-Guijon and Sergio Mendoza noted in a paper that was posted on the arXiv preprint server last month.