Swan A is one of the most powerful radio sources known. It is an elliptical galaxy 800 million years away from us. In the late 1980s, it was repeatedly observed by the VLA radio telescope complex. It turned out that two powerful jets are emanating from the center of Cygnus A - the product of the action of a supermassive black hole lurking in its center. The substance in the "tips" of these jets actively interacts with the surrounding intergalactic space, forming a shock wave, which, as a result, leads to intense radio emission. In his novel Contact, Carl Sagan made Swan A a product of the astro-engineering of alien civilizations trying to stop the expansion of the universe.
But even without any fiction, Swan A presented a small surprise. During the first observations of the galaxy since the late 1980s, the VLA complex discovered a new bright source of radiation near its center. It is located 1,300 light-years from the core. The team of astronomers who discovered the object revised the archive of old images of Cygnus A and noticed traces of it in the Keck Observatory infrared images taken in 2003 and in a couple of Hubble images. Its identification was made difficult by the fact that the object is not very noticeable in the visible spectrum.
As for the nature of the object, astronomers claim that it is not a background object. According to their theory, it may be a cluster of old stars - the remnants of the core of a galaxy once absorbed by Sagittarius A. There is also a supermassive black hole in its center. If she absorbed some object, it could "awaken" her, making it visible in the radio range. Well, maybe it really is the work of an extraterrestrial civilization, pulling matter into Swan A to save the Universe. I think this is not the worst option.