Boötes Void

The Boötes Void is a vast region of space in the direction of the constellation Boötes, containing far fewer galaxies than typical cosmic regions.

Cosmic void: A large region of the universe with a lower-than-average density of galaxies and matter. The Boötes Void is an unusually large, sparsely populated example of this general structure.
Boötes Void galaxy survey: Observational mapping of galaxies within and around the Boötes Void. Survey results establish how sparse the region is and where its galaxies lie.
Robert Kirshner: An American astronomer whose work includes studies of supernovae and the large-scale distribution of galaxies. He led the team that identified and publicized the Boötes Void.
Galaxy filament: An elongated, dense structure of galaxies and dark matter within the cosmic web. Filaments concentrate galaxies, unlike the low-density interior of the Boötes Void.
Large-scale structure of the universe: The distribution of galaxies and matter across the universe on scales larger than individual galaxy groups. The void is one low-density feature within this cosmic web of filaments, sheets, and voids.
Markarian 845: A galaxy in the direction of the Boötes Void, among the relatively few galaxies identified within its boundaries. It illustrates that the void is underpopulated, not entirely devoid of galaxies.
1981 Boötes Void discovery: The 1981 report of an exceptionally large region with few observed galaxies in Boötes. This discovery brought the void to attention as a striking feature of the galaxy distribution.
Galaxy cluster: A gravitationally bound structure containing hundreds to thousands of galaxies. Clusters are dense galaxy concentrations, the opposite extreme from the void's sparse interior.
Cosmic web: The network of galaxy filaments and clusters surrounding large, relatively empty regions of the universe. The Boötes Void occupies a particularly expansive gap in this network.
Boötes: A northern constellation whose name is Latin for herdsman. The void is named for the constellation in whose direction it appears.

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Giant VoidBroader topic: It is the best-known example of a giant void.