(large group of galaxies gravitationally-bound to the group)
A galaxy cluster (CL) is a group of on the order of
hundreds of galaxies bound to each other by gravity.
A smaller such group of galaxies is known as a galaxy group.
The vast majority of galaxies are in such clusters and groups.
The cluster often has an intergalactic medium including plasma.
The typical mass of a cluster is on the order of 1015
solar masses. A cluster can be part of a supercluster.
Shock waves from matter striking a galaxy cluster's
intracluster medium produce X-rays, which can be a
sign to observers of the presence of a galaxy cluster.
Such X-ray signals can reveal very distant clusters,
the furthest currently known (CL J1001+0220) being at redshift 2.5.
Example galaxy clusters:
The abbreviation CL is often included in designators for
galaxy clusters, e.g., for CL J1001+0220.
The term cluster can also refer to stellar clusters
such as open clusters, sometimes confusingly
called galactic clusters (meaning clusters within a galaxy,
i.e., the Milky Way).
|Prefix||Example|| || |
|CL||CL J1001+0220||general prefix for clusters|| |
Referenced by pages:
Atacama Cosmology Telescope (ACT)
Arecibo General Catalog (AGC)
Alcock-Paczyński effect (AP effect)
Arcminute Microkelvin Imager (AMI)
brightest cluster galaxy (BCG)
Canadian Cluster Comparison Project (CCCP)
cold dark matter (CDM)
Catalog of Galaxies and Clusters of Galaxies (CGCG)
cosmic infrared background (CIB)
cosmic distance ladder
dark matter halo
Dark Energy Survey (DES)
velocity dispersion (σ)
dark matter filament
Duus-Newell catalog (DN)
ESO Nearby Abell Cluster Survey (ENACS)
gravitational instability (GI)
giant elliptical galaxy
gravitational instability model
hierarchical assembly of galaxies
intracluster medium (ICM)
intergalactic medium (IGM)
Lambda-CDM model (ΛCDM)
large scale structure (LSS)
luminosity function (LF)
Massive Cluster Survey (MACS)
Munich Near-Infrared Cluster Survey (MUNICS)
planetary nebula luminosity function (PNLF)
rare designator prefixes
RR Lyrae variable (RRL)
star formation history (SFH)
South Pole Telescope (SPT)
supergalactic coordinate system
Sachs-Wolfe effect (SWE)
Sunyaev-Zel'dovich effect (SZ effect)
three dimensional model
wide binaries (WB)
weak lensing (WL)
XMM Cluster Survey (XCS)
X-ray luminous galaxy cluster
Zwicky 3146 (Zw 3146)