This system of two massive galaxies — located in the southern constellation of Eridanus — is called Arp-Madore 417-391. Two galaxies in the Arp-Madore 417-391 system (right) form a ring shape, which is narrow and blue, and the cores of the two galaxies form a bulge on the ring’s side. Two smaller spiral galaxies appear left of center as well as a few stars. Image credit: NASA / ESA / Hubble / Dark Energy Survey / DOE / FNAL / DECam /...
