Clump of active galactic cores that stretch 4 billion light-years from end to end. The structure is a light quasar group (LQG), a collection of extremely luminous Galactic Nulcei powered by supermassive central black holes.
How many matter particles exist in nature? Particle physicists have been dealing with this question for a long time. The 12 matter particles contained in the standard model of particle physics? Or are there further particles .