The Eridanus Cluster is a galaxy cluster roughly 23 Mpc (75 Mly) from Earth, containing about 73 main galaxies and about 200 total galaxies. About 30% have Hubble classifications of elliptical or S0 and the remaining 70% are spiral or irregular. These galaxies reside in smaller groups which are all loosely gravitationally bound to each other, suggesting that the system is still condensing from the Hubble flow and may eventually form a cluster of about 1014 M☉. A low velocity dispersion compared to that of, for example, the Coma cluster, supports this hypothesis. The Eridanus Cluster is located in the constellation Eridanus near the Fornax Cluster, and is sometimes called the "Fornax II Cluster".
The spiral galaxy NGC 1232 is one of the brightest in the Eridanus Cluster.
The barred spiral galaxy NGC 1300 is a well-known member of the Eridanus Cluster.
The Fornax Cluster is a cluster of galaxies lying at a distance of 19 megaparsecs (62 million light-years). It has an estimated mass of (7±2)×1013 solar masses, making it the second richest galaxy cluster within 100 million light-years, after the considerably larger Virgo Cluster. It may be associated with the nearby Eridanus Group. It lies primarily in the constellation Fornax, with its southern boundaries partially crossing into the constellation of Eridanus, and covers an area of sky about 6° across or about 28 sq degrees.
VLT Survey Telescope image of the Fornax Galaxy Cluster
NGC 1399 galaxy by the HST; 2.76′ view.