Step-by-step explanation:
Although this issue has not been totally resolved, many astronomers now believe that so-called quasars (quasi-stellar objects) are the second step in the formation and evolution of new galaxies. So far, all new galaxies have been observed at distances that place them in time only about one-billion years after the Big Bang event. It's generally accepted that the first step in new-galaxy formation must have been the formation of massive black holes located in dense regions of the the universal gas that filled the young universe. As immense quantities of this gassy material was accelerated into the black hole at near light speed, high-energy radiation was generated to flash outward. Some 12-billion years later we observe these radiation sources as quasars.