The Phoenix Cluster Is A Record-Breaking Galaxy Cluster

The Phoenix Cluster is impressive enough to make anyone's head spin. It's one of the biggest, brightest galaxy clusters ever discovered, and, trust us, that's just the beginning.

Too Big To Comprehend

The Phoenix cluster—formally known as SPT-CLJ2344-4243, so be thankful for its nickname—sits about 5.7 billion light years from Earth. Discovered in 2010, this cluster boasts some seriously impressive stats. Here's a quick rundown from NASA: "Stars are forming in the Phoenix Cluster at the highest rate ever observed for the middle of a galaxy cluster. The object is also the most powerful producer of X-rays of any known cluster, and among the most massive of clusters. The data also suggest that the rate of hot gas cooling in the central regions of the cluster is the largest ever observed."

But it doesn't stop there. Here are some more astonishing numbers to gawk over, as reported by

  • The cluster's central galaxy contains about 3 trillion stars. Compare that to the Milky Way's 200 billion or so.
  • The estimated mass of the black hole at the cluster's center is roughly 10 billion solar masses. In other words, it's about as massive as the biggest black hole ever discovered. The Milky Way's central black hole weighs a puny 4 million solar masses.
  • The galaxy in Phoenix's center generates about 740 new stars annually, a new high for the middle of a cluster. The Milky Way creates just one or two new stars on average ever year.

The Surprises Keep Coming

Seven years after the Phoenix Cluster was first discovered, scientists noticed more strange and amazing things going on here. A team of astronomers led by the University of Cambridge published their findings in the Astrophysical Journal: an unexpected connection between the supermassive black hole inside the Phoenix Cluster and the giant galaxy in which it sits. The team observed that "radio jets from the black hole—which normally suppress star formation—are stimulating the production of star-forming molecular gas in the galaxy's halo," reported Sci-News. Lead author of the research paper, Dr. Helen Russell from the University of Cambridge, said "This gives us new insights into how a black hole can regulate future star birth and how a galaxy can acquire additional material to fuel an active black hole."

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Written by Curiosity Staff April 22, 2017

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