Galaxy Clusters

There are four classifications types of galaxy clusters: regular,irregular, rich, and poor. Regular galaxy clusters are spherically shaped, and usually rich, which means they have thousands of galaxy members. Irregular clusters have no specific shape and are generally poor, having only about a hundred members or less.

Regular clusters are giant systems. Most of the galaxies in these clusters are elliptical or irregular. They can frequently contain 1000's of galaxy members. These clusters tend to form roughly spherical clouds. They also usually have very large galaxies in the center and spiral galaxies only on their edges, if they have them at all. Regular clusters often contain a lot of hot gas. An example of a regular cluster is the Coma cluster.

Irregular galaxy clusters can be many different shapes and densities. They can be small groups, a loose collection with many centers, or large and spread out. They typically do not contain as many galaxies as the regular type. Our galaxy is a member of an irregular cluster, known as the Local Group. This group contains approximately 30 members, including our Milky Way, Andromeda, the Large Magellanic Cloud, the Small Magellanic Cloud, and many other dwarf galaxies. It spans 1 Mpc at it's largest dimension.

Virgo Cluster

Galaxy clusters are usually members of an even larger cluster called a Supercluster. These superclusters, or a cluster of clusters of galaxies, span huge regions of the universe and have large voids of space in between them.

Here are some cool galaxy cluster links:

Images:
  • Galaxy Cluster Mug Shots
  • STScI releases
  • Galaxy Cluster formation movie


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    These pages designed by Erin McNally (CU'00)... Last modified 18Apr00