In the 1950s the astronomer Gérard de Vaucouleurs recognized the existence of a flattened “local supercluster” from the Shapley-Ames Catalog in the environment of the Milky Way. He noticed that when one plots nearby galaxies in 3D, they lie more or less on a plane. A flattened distribution of nebulae had earlier been noted by William Herschel over 200 years. Vera Rubin had also identified the supergalactic plane in the 1950s, but her data remained unpublished. The plane delineated by various galaxies defined in 1976 the equator of the supergalactic coordinate system he developed. In years thereafter with more observation data available de Vaucouleurs findings about the existence of the plane proved right.
The observed supergalactic plane is more or less perpendicular to the plane of the Milky Way, the angle is 84.5 degrees. The plane runs through the constellations Cassiopeia (in the galactic plane), Camelopardalis, Ursa Major, Coma Berenices (near the galactic north pole), Virgo, Centaurus, Circinus (in the galactic plane), Triangulum Australe, Pavo, Indus, Grus, Sculptor (near the galactic south pole), Cetus, Pisces, Andromeda, and Perseus.
Based on the super galactic coordinate system of de Vaucouleurs surveysin recent years determined the positions of galaxies, of nearby galaxy clusters relative to the supergalactic plane. Amongst others the Virgo cluster, the Norma cluster (including the Great Attractor), the Coma cluster, the Pisces-Perseus supercluster, the Hydra cluster, the Centaurus cluster, the Pisces-Cetus supercluster and the Shapley Concentration were found to be near the supergalactic plane.