Astronomers Discover a New Stage of Galaxy Evolution — the ‘Cold Quasar’

Quasars are supermassive black holes actively gobbling material from the galaxy around them. While black holes are known for pulling material in, the turbulent swirl of that whirlpool often also flings material and radiation out at high energies, enabling quasars to be seen from across the universe. They are some of the brightest objects astronomers know. But a quasar can be bad news for its host galaxy. To form stars, a galaxy needs reservoirs of cold gas that can clump together, not gas that’s being violently heated and swept away by a raging black hole.