Astronomers have discovered the largest known structure in the universe, a 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!
Although most galaxies fall into well defined classifications, there are some that defy all attempts at classification. While some strange and bizarre galaxies are the result of gravitational interactions with other more massive, and sometimes less massive objects, they all have one thing in common; they look more like artists’ impressions than real, tangible collections of billions of stars. Take a look at the stunning photos below credited to the NASA image gallery