Cosmic voids are the vast empty spaces between
filaments (the largest-scale structures in the
Universe), which contain
very few, or no,
galaxies. They were first discovered in 1978 during a pioneering study by Stephen Gregory and
Laird A. Thompson at the
Kitt Peak National Observatory. These zones have less than one-tenth of the average density of matter abundance that is considered typical for the
observable Universe. Voids typically have a diameter of 11 to 150
megaparsecs; particularly large voids, defined by the absence of rich
superclusters, are sometimes called "supervoids". Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe.