Supercluster

Superclusters represent the largest known structures in the universe, vast cosmic scaffolding containing thousands of galaxies organized into clusters and groups across distances of 100-500 million light-years. Unlike galaxy clusters, which are held together by gravity, superclusters exist as loose associations connected by dark matter filaments in the cosmic web.</p><p>Our Milky Way resides within the Virgo Supercluster, discovered in the 1950s by Gérard de Vaucouleurs, which spans roughly 110 million light-years and contains over 1,300 galaxies. However, recent research revealed we're actually part of an even larger structure called Laniakea (Hawaiian for "immeasurable heaven"), containing 100,000 galaxies across 520 million light-years. The most massive known supercluster, the Shapley Supercluster, lies 650 million light-years away and gravitationally influences our Local Group's motion through space.</p><p>Superclusters serve as crucial laboratories for understanding cosmic evolution, dark matter distribution, and the universe's large-scale structure. They form along filaments of the cosmic web, separated by vast cosmic voids containing few galaxies. While gravity binds their constituent clusters internally, superclusters themselves are gradually dispersing due to cosmic expansion, making them temporary features lasting only billions of years—brief moments in cosmic time.