A new image from ESA’s Euclid telescope shows approximately 1,000 galaxies belonging to the Perseus cluster — a cluster of galaxies 240 million light-years away in the constellation of Perseus — and more than 100,000 additional galaxies further away in the background.
Approximately 11 million light-years across and located 240 million light-years away, the Perseus cluster is named for its host constellation.
Also known as Abell 426, it is one of the most massive objects in the observable Universe, containing over 1,000 galaxies immersed in a vast gas cloud.
Like all galaxy clusters, most of its observable matter takes the form of a pervasive gas averaging tens of millions of degrees, so hot it only glows in X-rays.
The galaxy sitting in the center of the Perseus cluster is NGC 1275, a very peculiar galaxy that emits abundant radio signals, for this known as Perseus A.
The cluster also hosts several other radio galaxies with complex structure, including NGC 1265, NGC 1272, CR 15, and IC 310.
“Perseus is one of the most massive structures known in the Universe, located ‘just’ 240 million light-years away from Earth, containing thousands of galaxies, immersed in a vast cloud of hot gas,” Euclid Consortium scientists said.
“Astronomers demonstrated that galaxy clusters like Perseus can only have formed if dark matter is present in the Universe.”
“If no dark matter existed, galaxies would be distributed evenly throughout the Universe,” said Euclid Consortium scientist Dr. Jean-Charles Cuillandre, an astronomer at CEA Paris-Saclay.
“Gravity causes dark matter to form filamentary structures often referred to as the cosmic web.”
“The crossing points between dark matter filaments cause galaxies to stick close together, creating a cluster.”
“The cosmic web permeates the whole Universe, and similar structures are seen way beyond Perseus, as far as 12 million light-years away.”
Many galaxies in this cluster are already known, but Dr….
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