Revealing quasars’ true colours

Our astronomers have identified a rare moment in the life of some of the universe's most energetic objects. Now Durham University's researchers have found a phase in the development of these galactic giants that could tell us more about how quasars and their host galaxies evolve. However, a significant number of quasars look red when viewed through the huge clouds of dust and gas that obscure them from view. The conventional view of red quasars is that they are actually blue quasars that are angled away from our line-of-sight. Red quasars. Our team has ruled out this model and instead has shown that red quasars are likely to be the result of a brief, but violent, phase in the evolution of galaxies when their black holes are ejecting large amounts of energy into the surrounding dust and gas. This injection of energy blows away the dust and gas to reveal a blue quasar.