The Big Bang and Inflation theories both explain a universe that is expanding in general, but on a smaller scale, galaxies are found to be in clusters of varying sizes.

The Local Group

The local group is the group of galaxies to which the Milky Way belongs. It includes about two dozen galaxies, including Andromeda and the large and small Magellanic Clouds. The Milky Way and Andromeda are the two largest galaxies in the local group. Until recently it was assumed that Andromeda was the largest, but, as evidence accumulates, allowing us to better estimate the size of our own galaxy, it may turn out that the Milky Way is the largest member of the Local Group.

Superclusters and Strands

Newer surveys and computer models are allowing us to better visualize the universe, revealing large-scale structures, including groups of galaxies and strings of clusters of groups of galaxies. These images also reveal relatively empty regions of the universe.

The Virgo Group

The Virgo Group of Galaxies includes 2 super-Giant-Sized Ellipticals. It also contains dozens of spirals and irregulars the size of the Milky way. Our local group may be orbiting the Virgo group. In other words, we may be part of the Virgo Super-cluster.

Galaxy Surveys