2022-03-24 / Click on image to enlarge
The group of four prominent galaxies seen in this image is Hickson 44, a so called compact group of galaxies, named after the Canadian astronomer Paul Hickson. The group lies about 80-100 million light-years away from Earth toward the constellation Leo. The two spiral galaxies in the center of the image are edge-on NGC 3190 with its distinctive, warped dust lanes, and S-shaped NGC 3187. Along with the bright elliptical, NGC 3193 at the top left, they are also known as Arp 316. The spiral below is NGC 3185, the 4th member of the Hickson group.
Current theory says that compact groups represent physically related galaxies that are in the process of merging into a single object, most likely an elliptical galaxy. Compact groups are relatively short-lived entities that form via mergers of galaxies within loose subsystems and groupings. Simulations predict that merging of the group members should proceed rapidly within one billion years to form an elliptical galaxy. Like other galaxies in Hickson groups, Hickson 44 shows signs of distortion and enhanced star formation, evidence of a gravitational tug of war that will eventually result in galaxy mergers on a cosmic timescale.