Abell 2151, the Hercules Galaxy Cluster, is a collection of about 100 galaxies lying approximately one-half billion light years from Earth. I counted about 70 “fuzzies” in the above image which I believe to be galaxies. Abell 2151 is part of a much larger structure known as The Great Wall, a collection of galaxy clusters, superclusters, and clusters of superclusters forming a thin sheet about 15 million light years thick by 500 million light years long by 200 million light years wide. This massive collection of galaxies is the largest known structure in the Universe at the present time. Contained within Abell 2151 are four Arp objects, they being Arp 71, 122, 172 and 272. Arp 71 is the nearly edge-on spiral with a small companion off its right arm located in the center of the image. Arp 122 is left of center about half way to the edge and consists of a spiral and elliptical galaxy interaction. Arp 172 can be seen in the upper right as the interaction of two large ellipticals with distorted halos. Finally, Arp 272 is the interacting pair of nearly face-on spiral galaxies just right of center.

Not unlike the Hubble Deep Field image of countless galaxies imaged in a tiny portion of the sky in the direction of Ursa Major, the Hercules Galaxy Cluster can perhaps be considered an equivalent opus aptly named the Amateur Deep Field image.