Larger Clusters and Superclusters

Larger clusters are a vast group of galaxies, bound by gravity, generally made up of hundreds to thousands of galaxies.
These constitute some of the largest known structures of the universe, often spanning tens of millions of light-years across.
The Milky Way belongs to a larger cluster known as the Local Group, which is about 10 million light-years in diameter and consists of around 54 different galaxies.
Larger clusters are often characterised by large amounts of hot, X-ray emitting gas and a significant amount of dark matter. The mass of the hot gas and the dark matter greatly exceeds the mass of the galaxies themselves.
Larger clusters often contain a rich variety of different galaxy types, including spiral, elliptical, and irregular galaxies.
Typically, these clusters are arranged with a concentration of galaxies toward the centre, and fewer galaxies on the outskirts. This is referred to as a centrally concentrated distribution.

A supercluster is a vast group of galaxies, composed of multiple clusters.
The Virgo Supercluster, for instance, is a supercluster that includes the Local Group, home to our Milky Way galaxy, and about 100 other galaxy groups and clusters.
Superclusters are amongst the largest known structures in the universe, covering billions of light-years.
They help astronomers understand the overall structure of the universe and its cosmic web-like distribution on vast scales.
Astronomers think that superclusters are temporary and won’t exist in their present form in the far, far future. This is because the cosmological expansion, the steady increase in space over time, is thought to eventually break up superclusters.
The term Laniakea Supercluster is used to describe our local supercluster which means ‘immeasurable heaven’ in Hawaiian.

Investigating these structures help us comprehend the large scale structure of the universe and the distribution of matter within it.
They allow us to understand how gravitational forces shape the universe and propagate structures on different scales.
Exploring clusters and superclusters aids in probing the matter content of the universe, in particular, the puzzling dark matter.
They offer opportunities to investigate the cosmological principle, the idea that the distribution of matter in the universe is homogeneous and isotropic when viewed on a large enough scale.
Finally, it helps in the quest to understand more about cosmological evolution and the future fate of our universe.