group cluster

astronomy

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June 17, 2026

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A cluster of galaxies is a gravitationally bound grouping containing hundreds to tens of thousands of galaxies. These clusters often emit X-rays from hot intergalactic gas and can deplete galaxies of their interstellar gas through interactions. Our own Milky Way Galaxy is part of the Local Group, which is near the Virgo Cluster.1

Galaxies are not evenly distributed; they form larger structures called superclusters, which are collections of galaxy clusters. The space between these superclusters is relatively empty, forming voids. The existence of dark matter is inferred from its gravitational pull, not its light, and it plays a crucial role in holding galaxies and clusters together.234

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galaxy
Groups
The groups class is composed of small compact groups of 10 to 50 galaxies of mixed types, spanning roughly five million light-years. An example of such an entity is the Local Group, which includes the Milky Way Galaxy, the Magellanic Clouds, the Andromeda Galaxy,…
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The groups class is composed of small compact groups of 10 to 50 galaxies of mixed types, spanning roughly five million light-years. An example of such an entity is the Local Group, which includes the Milky Way Galaxy, the Magellanic Clouds, the Andromeda Galaxy,…
Read More