Superclusters are large groupings of smaller galaxy groups and clusters, and are among the largest structures of the cosmos. The existence of superclusters indicates that the galaxies in our Universe are not uniformly distributed; most of them are grouped together in groups and clusters, with groups containing up to 50 galaxies and clusters up to several thousand. Those groups and clusters and additional isolated galaxies in turn form even larger structures called superclusters.
Superclusters can range in size up to several 108 light years. No clusters of superclusters are known, but the existence of structures larger than superclusters is debated (see Filament). Interspersed among superclusters are large voids of space in which few galaxies exist. Even though superclusters are the largest structures confirmed, the total number of superclusters leave possibilities for structural distribution; the total number of superclusters in the universe is believed to be close to 10 million.
Superclusters are frequently subdivided into groups of clusters called galaxy clouds.
The following is a list of some nearby superclusters.
See also
External link