How after the collision of two galaxies, they have turned into a huge ring, and their cores have come side by side, this ring of galaxies is known as Arp-Madore 417-391. The Arp-Madore Catalog is a collection of galaxies in particular, spanning the entire southern sky, that includes subtle interacting galaxies as well as more spectacular colliding galaxies.
Arp-Madore 417-391 is located approximately 670 million light-years away in the Eridanus constellation in the southern celestial hemisphere, a gravitationally warped collision of galaxies. Hubble used the Advanced Camera for Surveys (ACS) to capture the image of Arp-Madore 417-391,The Advanced Camera for Surveys (ACS) is optimized for detecting galaxies and galaxy clusters in the ancient universe. From mapping dark matter to studying the evolution of galaxy clusters, they have helped.