Fr.: superamas de Shapley
The richest → supercluster of galaxies in the nearby → Universe at a → redshift going from z ~0.03 to z ~0.05 (680 million → light-years), and extending over several square degrees on the plane of the sky. It lies behind the → Centaurus supercluster. Also called the Shapley concentration, it is made up of 25 → galaxy clusters with a total mass of about 1016→ solar masses. At the core of the Shapley supercluster is a remarkable complex formed by several rich clusters of galaxies from the → Abell catalog; the central and most massive of them is A3558.