Astronomers detailed a group of four quasars in the same gas cloud in a new study that should advance theories on how they form.
According to Discovery News, quasars are typically seen along and their sightings are fairly rare. It is also hard to get long looks at quasars, since they only show up when a supermassive black hole reaches the peak of its intake.
The new study is published in the journal Science.
"If you discover something which, according to current scientific wisdom, should be extremely improbable, you can come to one of two conclusions: either you just got very lucky, or you need to modify your theory," study lead author Joseph Hennawi, of the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany, said in a press release.
This is the first quartet of quasars seen together and past studies have observed two triplets and about 100 pairs, Discovery News reported. Each of the four were calculated to be as much as 650,000 light years from one another, about a quarter of the distance between the Milky Way and Andromeda galaxies.
"Our current models of cosmic structure formation based on supercomputer simulations predict that massive objects in the early universe should be filled with rarefied gas that is about ten million degrees, whereas this giant nebula requires gas thousands of times denser and colder," study co-author Sebastiano Cantalupo, of the University of California - Santa Cruz, said in the release.
In addition to being ultra rare, the team determined their discovery was a one-in-10-million chance that it was not made by happenstance.
"It may be that quasar episodes are more likely to be triggered in such an unusual environment, which is rich in both gas and galaxies," Hennawi told Discovery News. "Current models of how structure forms in the universe would never predict that there would be so much cool, dense gas around. Instead, those models predict that the gas in such a massive object should be 1,000 times hotter and 1,000 times less dense."
