The Coma Cluster through Esprit150SX46 for Lum 6hrs and Esprit100ASI1600 for RGB 2hrs per channel

The Coma Cluster (Abell 1656) is a large cluster of galaxies that contains over 1,000 identified galaxies. The cluster's mean distance from Earth is 321 million light years. The central region is dominated by two supergiant elliptical galaxies: NGC 4874 and NGC 4889. The cluster is within a few degrees of the north galactic pole on the sky. Most of the galaxies that inhabit the central portion of the Coma Cluster are ellipticals. Both dwarf and giant ellipticals are found in abundance in the Coma Cluster.

NGC 4874 is a supergiant elliptical galaxy. Discovered by William Herschel in 1785. The second-brightest galaxy within the northern Coma Cluster, it is located at a distance of 350 million light-years from Earth. The galaxy is surrounded by an immense stellar halo that extends up to one million light-years in diameter. It is also enveloped by a huge cloud of interstellar medium that is currently being heated by action of infalling material from its central supermassive black hole. A jet of highly energetic plasma extends out to 1,700 light-years from its center. The galaxy has 18 700 ± 2260 globular clusters.

NGC 4889 is an E4 supergiant elliptical galaxy. It was discovered in 1785 by William Herschel. The brightest galaxy within the northern Coma Cluster, it is located at a median distance of 308 million light year from Earth. At the core of the galaxy is a supermassive black hole that heats the intracluster medium through the action of friction from infalling gases and dust.

As the largest and the most massive galaxy easily visible to Earth, NGC 4889 has played an important role in both amateur and professional astronomy, and has become a prototype in studying the dynamical evolution of other supergiant elliptical galaxies in the more distant universe.

NGC 4921 is a barred spiral galaxy in the Coma Cluster, located in the constellation Coma Berenices. It is about 320 million light-years from Earth. The galaxy has a nucleus with a bar structure that is surrounded by a distinct ring of dust that contains recently formed, hot blue stars. The outer part consists of unusually smooth, poorly distinguished spiral arms.

NGC 4911 is a disturbed, warped spiral galaxy with a bright prominent central starburst NGC 4911 is believed to be interacting with its warped, barred lenticular companion (or any of its many other nearby companions), producing the enhanced star formation and shell-like appearance seen in optical images. The galaxy contains rich lanes of dust and gas near its centre. The existence of clouds of Hydrogen within the galaxy indicates ongoing star formation. This is rare for a spiral galaxy to be situated at the heart of a cluster.

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