Astronomers discover rare quasar quartet in close proximity

Finding a single quasar in space is something rare in astronomy and scientists say that quasars are usually separated by hundreds of millions of light years. That isn't the case with a recently discovered quartet of quasars that are in close proximity to each other. The quasars are indicated in the image by the arrows and scientists say that the blue haze is a nebula made of cool and dense gas that the quasars are inside.

Scientists believe that quasars are the nuclei of early galaxy formation and they are powered by matter being sucked into super massive black holes at the center of a galaxy. The odds of finding four quasars in close proximity are about one in ten million according to the researchers.

Researchers say that the light from the quasars took ten billion years to reach the Earth and show what the galaxy was like less than 4 billion years after the big bang. Multiple quasars in close proximity like this suggest protoclusters were forming according to the researchers; these are the forerunners of massive galaxy clusters.

Finding these quasars so close to each other in a massive nebula of cool and dense gas may force scientists to reconsider the models of quasar evolution and formation used to date. The current predictions that scientists have about quasars suggest that the early universe was filled with gas at about ten million degrees, yet this nebula around the quasars is not hot. The cool and dense hydrogen gas did help scientists to discover the quasars because the gas was irradiated by the intense light from the quasars.