A team of international astronomers has discovered a rare and colossal cluster of galaxies that is turning preconceived notions on their head -- and giving scientists plenty of fodder for inventive metaphors.
According to a release, the discovery shows a "beast of a galaxy cluster whose heart is bursting with new stars."
SpARCS1049+56 -- as the cluster has been tagged -- is 9.8 billion light years from Earth, contains at least 27 individual galaxies and has a total mass equal to about 400 trillion suns.
Scientists say the dominant galaxy at the cluster's heart is stealing gas from a neighbor galaxy as it spits out an incredible 860 stars per year. For contrast, our Milky Way galaxy gives birth to only one or two new stars per year.
The discovery -- originally made with telescopes atop Mauna Kea on Hawaii's Big Island -- is the first to show that gigantic galaxies at the center of massive clusters can grow significantly by feeding off gas stolen from other galaxies.
Tracy Webb of McGill University in Montreal, the lead author of the study, said in a statement that usually stars at the centers of galaxy clusters are old and dead, essentially fossils.
"But we think the giant galaxy at the center of this cluster is furiously making new stars after merging with a smaller galaxy," she said.
After making initial observations with the Hawaii telescopes, astronomers turned to NASA's Hubble Space Telescope to pinpoint what was fueling the "furious episode of new starbirth."
"Hubble found a trainwreck of a merger at the centre of this cluster,"Adam Muzzin of the University of Cambridge said in a release. There was also the presence of "beads on a string," or pockets of gas that condense where new stars are forming.
CFH says such gas pockets are a telltale sign of collisions between gas-rich galaxies, a phenomenon known to astronomers as "wet mergers," where gas is quickly converted to new stars. Dry mergers, on the other hand, occur when galaxies with little gas collide and no new stars are formed.
The new discovery is reportedly one of the first known cases of a wet merger at the core of a distant galaxy cluster.
“It is very exciting to have discovered such an interesting object,” Wilson said. “Understanding its nature proved to be a real scientific challenge which required the combined efforts of an international team of astronomers and many of the world’s best telescopes to solve. "