An Etymological Dictionary of Astronomy and Astrophysics
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The nearest large → supercluster. It is dominated by the → galaxy cluster A3526 (→ Abell catalog). The Centaurus supercluster is a long structure that stretches away from us. The most distant of the clusters, A3581, is about 300 million → light-years away.

→ Centaurus; → cluster.

A → supercluster of galaxies that includes our → Local Group and about 300 to 500 known → galaxy clusters and groups. Also called → Local Supercluster. If approximated as round, it has a diameter of 12,000 km s^-1 in units of the → cosmic expansion or 160 megaparsecs, and encompasses about 10¹⁷ → solar masses. Our Local Group lies toward the outer regions of Laniakea. Its main components are the four previously known superclusters: → Virgo supercluster (the part where the → Milky Way resides), Hydra-Centaurus Supercluster (including the → Great Attractor, Antlia Wall, known as Hydra Supercluster, → Centaurus supercluster), Pavo-Indus Supercluster, and Southern Supercluster (including Fornax Cluster, Dorado and Eridanus clouds). The most massive galaxy clusters of Laniakea are Virgo, Hydra, Centaurus, Abell 3565, Abell 3574, Abell 3521, Fornax, Eridanus, and Norma. The Laniakea supercluster was discovered by Tully et al. (2014, Nature 513, 71).

From the Hawaiian words lani "heaven," and akea "spacious, immeasurable;" → supercluster.

The supercluster to which the Local Group belongs. It is composed of some 100 clusters of galaxies, with the Virgo cluster of galaxies at its center.

→ local; → supercluster.

A long, dense chain of galaxies with a length of almost 300 million → light-years, constituting one of the largest known structures in the → Universe. At the left end of the supercluster lies the massive → Perseus cluster (A426), one of the most massive clusters of galaxies within 500 million light-years.

→ Perseus; → Pisces; → cluster.

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.

→ Shapley's wing; → supercluster

1) An aggregation of clusters of galaxies (→ galaxy cluster). Superclusters are typically about one hundred million (10⁸) → light-years in diameter and contain tens of thousands of galaxies. Some examples are the → Local Supercluster, → Centaurus supercluster, → Laniakea supercluster, → Perseus-Pisces supercluster→ Shapley supercluster→ Virgo supercluster.
2) For stellar aggregations, → dynamical stream.

→ super-; → cluster

Grouping of galaxies in supercluster structure.

→ super-; → clustering

The irregular supercluster that contains the Virgo cluster and the Local Group. At least 100 galaxy groups and clusters are located within its diameter of 110 million light-years. It is one of millions of superclusters in the observable Universe.

→ Virgo; → supercluster.