Astrophysics (Index)About

galaxy cluster

(CL, cluster)
(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 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).


(galaxies,object type)
Further reading:
http://en.wikipedia.org/wiki/Galaxy_cluster
PrefixExample  
CLCL J1001+0220general prefix for clusters

Referenced by pages:
Abell Catalog
ACIS
Atacama Cosmology Telescope (ACT)
Arecibo General Catalog (AGC)
Alcock-Paczyński effect (AP effect)
astronomical quantities
baryonic matter
brightest cluster galaxy (BCG)
bremsstrahlung
Bullet Cluster
Canadian Cluster Comparison Project (CCCP)
cold dark matter (CDM)
Catalog of Galaxies and Clusters of Galaxies (CGCG)
cosmic infrared background (CIB)
cluster radius
CMB lensing
Comet Galaxy
comoving units
Compton scattering
computational astrophysics
cooling flow
cosmic distance ladder
cosmic web
cosmological simulation
dark flow
dark matter
dark matter halo
Dark Energy Survey (DES)
diffuse emission
velocity dispersion (σ)
dark matter filament
Duus-Newell catalog (DN)
elliptical galaxy
ESO Nearby Abell Cluster Survey (ENACS)
ESO 137-001
extended source
extragalactic astronomy
field galaxy
galaxy bias
galaxy filament
galaxy group
gas fraction
gravitational instability (GI)
gravitational instability model
gravitational lensing
gravitational redshift
gravity
Great Wall
HIRAX
Hubble expansion
Hydra-Centaurus Supercluster
intracluster medium (ICM)
intergalactic medium (IGM)
intensity mapping
Lambda-CDM model (ΛCDM)
Laniakea Supercluster
large scale structure (LSS)
luminosity function (LF)
Massive Cluster Survey (MACS)
metallicity (Z)
mock catalog
Munich Near-Infrared Cluster Survey (MUNICS)
non-Gaussian (NG)
Perseus-Pisces Supercluster
Planck
plasma
planetary nebula luminosity function (PNLF)
projected separation
radio relics
rare designator prefixes
redshift survey
RHAPSODY
ROSAT
RR Lyrae variable (RRL)
Scott effect
star formation history (SFH)
South Pole Telescope (SPT)
standard candle
stellar dynamics
supercluster
supergalactic coordinate system
Sachs-Wolfe effect (SWE)
systemic velocity
Sunyaev-Zel'dovich effect (SZ effect)
Thermal Bremsstrahlung
3C 295
three dimensional model
21-cm experiment
21-cm line
ultraviolet astronomy
Virgo Cluster
Virgo Supercluster
virial theorem
wide binaries (WB)
weak lensing (WL)
WINGS
XMM Cluster Survey (XCS)
X-ray luminous galaxy cluster
X-ray source
Zwicky 3146 (Zw 3146)

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