Supercluster

Large group of smaller galaxy clusters or galaxy groups

A supercluster is a large group of smaller galaxy clusters or galaxy groups; they are among the largest known structures in the universe. The Milky Way is part of the Local Group (containing more than 54 galaxies), part of the Laniakea Supercluster, contained within the larger Pisces–Cetus Supercluster Complex. The large size and low density of superclusters means that most of them, unlike clusters, expand with the Hubble expansion.

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