Local Group of Galaxies

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Related to Local Group of Galaxies: Local Cluster
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Local Group of Galaxies


the group of nearest galaxies, the distances to which do not exceed 1 million parsecs (about 3 million light-years). It consists of two large groups with dwarf galaxies scattered between them—a total of about 30 members. Our galaxy and the nearby Magellanic Clouds dominate the first group in terms of size, mass, and intensity of light. A spiral galaxy—the Andromeda Nebula—which is still more powerful, occupies a central place in the second group. A smaller spiral galaxy—M 33 in Triangulum—two small elliptical galaxies, and several dwarf galaxies are located nearby. The dwarf galaxies, the smaller ones sometimes being called intergalactic star clusters, are divided into irregular and spheroidal galaxies, or Sculptor-system galaxies (after the constellation in which such a galaxy was first discovered). Apparently, the dimensions and intensity of light of galaxies do not have any lower limit, so that galaxies may be extremely faint.

Faint dwarf galaxies undoubtedly constitute the greater part of objects in the universe, but they cannot be observed at great distances. It may therefore be that the local group is not an isolated dense formation but only that part of the metagalaxy that surrounds us and whose population has been most completely clarified. Galaxies that are part of the local group are accessible to the most detailed study owing to their proximity to us.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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