Astronomers have identified three main categories of celestial associations: individual galaxies, galaxy groups, and galaxy clusters. However, there is a lesser-known but equally fascinating type of celestial association: galaxy groups.

Unlike galaxy clusters, which can have hundreds or thousands of members, galaxy groups typically contain no more than 50 galaxies. These groups are composed of a mixture of large galaxies, such as spirals and ellipticals, as well as smaller and irregular galaxies.

One of the most notable examples of galaxy groups is the Local Group, to which we belong. This group includes familiar galaxies such as the Milky Way, the Andromeda galaxy (M31), and the Whirlpool galaxy (M33). It is a smaller grouping of galaxies that can be found in the local universe.

For astronomers and observers, galaxy groups offer interesting targets for observation. One of them is the Leo Trio, also known as the M66 Group. It is composed of three beautiful spiral galaxies: M65, M66, and NGC 3628. These galaxies, located in the Leo constellation, can be observed with binoculars or telescopes.

Other notable galaxy groups include the M81 Group, with the famous galaxy M81 accompanied by its neighbor, the dwarf galaxy NGC 5195. The Whirlpool galaxy, also known as M51, is another fascinating target as it is accompanied by the smaller galaxy NGC 5195.

Exploring galaxy groups provides valuable information about the formation and evolution of galaxies. By studying the interactions and dynamics within these groups, astronomers can better understand the large-scale structures of the universe.

Source: Astronomy Magazine, May edition.