Briefly: Astronomers at MIT have found beforehand unidentified galaxy clusters that have been missed by earlier research. Their outcomes, which have been lately revealed in The Astrophysical Journal, recommend that as many as one p.c of galaxy clusters could possibly be misidentified as a single shiny galaxy.
Clusters of galaxies containing tons of and even 1000’s of particular person galaxies are held collectively by gravity. As MIT highlights, they transfer by means of a sea of scorching fuel known as the intracluster medium, and provides off X-ray radiation that we will see utilizing space-based telescopes.
This radiation creates a “fuzzy halo” round galaxy clusters, making them simpler to establish versus an object with a single supply of X-rays, like a star or quasar.
As MIT Affiliate Professor Michael McDonald found in 2012, nonetheless, not all clusters adhere to this normal principal. The cluster he found, dubbed the Phoenix cluster, incorporates a black gap that emits X-rays shiny sufficient to drown out the radiation from the intracluster medium. Thus, it seemed like a single X-ray supply and was misclassified for many years.
Armed with this new risk, the Clusters Hiding in Plain Sight (CHiPS) survey got here to life. Throughout its six-year run, the survey recognized three new galaxy clusters, one in all which is analogous to the Phoenix cluster. That’s notable contemplating astronomers solely know of only a few Phoenix-style clusters.
McDonald hopes that the CHiPS survey outcomes will assist others, like these working with the eROSITA X-ray instrument, higher perceive find out how to seek for clusters.
“The individuals which can be constructing out the cluster searches for this new X-ray telescope want to concentrate on this work,” McDonald stated. “Should you miss one p.c of the clusters, there is a basic restrict to how nicely you possibly can perceive the universe.”
Photos courtesy Triff