Active galactic nucleus introduction
The active galactic nucleus (abbreviated as AGN) is the core of a class of highly active extragalactic galaxies in extragalactic bodies, which can be defined as: its main feature is nuclear activity, which is produced in stars Another energy source other than thermonuclear reactions, and has considerable influence in certain phenomena. This definition is non-quantitative. The nucleus of a normal galaxy is also active, so the lower boundary of the active galaxy nucleus can be extended to some normal galaxies, such as our Yinxin. The galaxies that live in the core of active galaxies are called active galaxies. In the most active quasars, the background galaxies have very little effect. They often only talk about the nucleus. Galaxy core.