A

David

Darling

Hercules Cluster (Abell 2151)

Hercules Cluster (Abell 2151)

The Hercules Cluster (Abell 2151) is a loose unsymmetrical cluster of about 75 bright galaxies, some 500 million light-years away in the constellation Hercules and about 6 million light-years across. It contains an unusually high proportion of spiral galaxies and also galaxies that shown evidence of interaction or other peculiar features (see galaxy interaction).