Astronomy is an exciting branch of science where astronomers get to research, study and discover new planets, stars and even galaxies. Over the decades, several galaxies have been found and placed into categories. Before a universe is given a name, astronomers look at several aspects to ensure that it can be categorized as a galaxy and to also identify which category it belongs in. So far, there are four groupings and particular qualities that qualify them to be in these groups. Here are the types and how astronomers identify the clusters.
Elliptical clusters are the rarest kind, and they are identified through their double rings and lack of a nucleus. The galaxies are commonly referred to as Hoag-type clusters, and an ideal example is the 1000714 galaxy. Although elliptical clusters are rare, they have the most massive galaxies containing trillions of stars and also the minutest clusters containing only a handful of stars.
Most of the universes that have been identified so far fall under this category. The spiral arms that surround a spinning diskette at the centre is the easiest way to identify these clusters. The flat disk spins so fast, and astronomers believe that there is usually a black hole at the bulge which is generally at the centre of these galaxies.
Barred spiral galaxies are spiral galaxies that possess bar-like features. The Milky Way, which is the galaxy we are in, is classified under this category. The bars seen on these galaxies are aligned with stars from the centre of the nucleus to the disk. Spiral barred galaxies consist of both old and newly formed stars.
As the name suggests, these galaxies have no definite shape and have been described to be chaotic. Most of them are small in size compared to the other galaxies; therefore, they are easy to spot. The very first galaxy to be detected by astronomers, GN-z11, belongs to this category.