The Ursa Major Cluster (Ursa Major I Cluster, UMa I ClG) is a spiral-rich galaxy cluster

Galaxy cluster

A galaxy cluster is a compact cluster of galaxies. Basic difference between a galaxy group and a galaxy cluster is that there are many more galaxies in a cluster than in a group. Also, galaxies in a cluster are more compact and have higher velocity dispersion. One of the key features of cluster is...

 of the Virgo Supercluster

Virgo Supercluster

The Virgo Supercluster or Local Supercluster is the irregular supercluster that contains the Virgo Cluster in addition to the Local Group, which in turn contains the Milky Way and Andromeda galaxies. At least 100 galaxy groups and clusters are located within its diameter of 33 megaparsecs...

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One of its biggest galaxies are NGC 3631, NGC 3953

NGC 3953

NGC 3953 is a barred spiral galaxy located in the constellation Ursa Major.-Supernovae:Two supernovae have been identified within NGC 3953: the type Ia supernova SN 2001dp and SN 2006bp.-Environment:...

, M109

Messier 109

Messier 109 is a barred spiral galaxy approximately away in the constellation Ursa Major. M109 can be seen southeast of the star Phecda .-History:Messier 109 was discovered by Pierre Méchain in 1781...

 on North and NGC 3726, NGC 3938 NGC 4051

NGC 4051

NGC 4051 is a spiral galaxy. It contains a supermassive black hole inside the center.This galaxy was studied by the Multicolor Active Galactic Nuclei Monitoring 2m telescope. -External links:...

 on South.

The Ursa Major cluster is located at a distance of 18.6 megaparsecs (60 million light years) and contains about 30% of the light but only 5% of the mass of the nearby Virgo cluster

Virgo Cluster

The Virgo Cluster is a cluster of galaxies whose center is 53.8 ± 0.3 Mly away in the constellation Virgo. Comprising approximately 1300 member galaxies, the cluster forms the heart of the larger Local Supercluster, of which the Local Group is an outlying member...

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