Abell 1656 – Coma Cluster – 2015-05-18

Coma Cluster (Abell 1656)
Imaged 2015-05-18

The Coma Cluster is a large cluster of galaxies that contains over 1,000 identified galaxies. Th image below shows a just a few hundred. The magnitudes of the ten brightest galaxies are between 12–14. The two largest galaxies at the centre are supergiant elliptical galaxies: NGC 4874 and NGC 4889. The Coma Cluster is part of the Coma Supercluster.

Abell 1656 - Coma Cluster - crop - 2015-05-18

Abell 1656 – Coma Cluster – crop – 2015-05-18

As its name implies, the cluster is located in the direction of the constellation Coma Berenices. While the three bright stars in the constellation are between 28 Mly and 167 Mly from us, the Coma Cluster of Galaxies is 321 Million lights years away.

The North Galactic Pole is located in Coma Berenices. So looking towards Coma Berenices is then looking up from the galactic plane and therefore there are fewer stars than when looking through the plane.

The Coma Cluster is one of the first places where dark matter began to be suspected. In 1933 Fritz Zwicky showed that the galaxies of the Coma Cluster were moving too fast for the cluster to be bound together by the visible matter of its galaxies. It is now thought that about 90% of the mass of the Coma cluster is dark matter.

Image details:
AT106 with AT2FF
Canon T2i (Astronomy UV/IR filter mods)
– 17 x 600sec frames at ISO1600 (total integration time 2hr 50m
Guided with Shorttube 80 and Chameleon
Metaguide with FlexRX
Image capture with Backyard EOS
Calibrated, stacked and processed with PixInsight
Cropped, original pixel scale