Astrophysics (Index)About

satellite galaxy

(galaxy that orbits a larger galaxy)

A satellite galaxy is a small galaxy, often a dwarf galaxy, orbiting a larger galaxy. Most of the galaxies of the Local Group are satellites of the Milky Way or Andromeda (M31). Some of the 30+ known satellites of the Milky Way:

Among Andromeda's satellites:

The exact number of satellite galaxies of the Milky Way and Andromeda are unclear as they are still being discovered, there is often discussion as to whether something constitutes a galaxy versus a globular cluster, and knowing whether it is orbiting depends upon its velocity, and such velocity-determination is non-trivial and undergoes corrections over time. Satellites in the Local Group are still being discovered and dwarf galaxies are often even more challenging to identify in more distant groups and clusters.

A galaxy subgroup (e.g., the Milky Way subgroup) is a galaxy and its satellites. The term hypergalaxy (a term which I suspect is rarely used) refers to a subgroup consisting of a major spiral galaxy and its satellites.


(galaxy type)
Further reading:
https://en.wikipedia.org/wiki/Satellite_galaxy
https://en.wikipedia.org/wiki/Satellite_galaxies_of_the_Milky_Way
http://www.atlasoftheuniverse.com/sattelit.html
http://astronomyonline.org/OurGalaxy/SatelliteGalaxies.asp

Referenced by pages:
Andromeda (M31)
Centaurus A
conditional stellar mass function (CSMF)
core-cusp problem
dark matter halo
dwarf galaxy
dwarf galaxy problem
dynamical friction
galactic halo
galaxy
galaxy group
galaxy subgroup
Hydrogen Accretion in Local Galaxies Survey (HALOGAS)
hypergalaxy
Large Magellanic Cloud (LMC)
Local Group (LG)
Local Sheet
Magellanic Clouds (MC)
Milky Way (MW)
Milky Way subgroup
PAndAS
Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS)
quenched galaxy
Sagittarius Dwarf Elliptical Galaxy (Sgr dE)
satellite plane problem
stellar halo
stellar overdensity
stellar stream
Triangulum Galaxy (M33)
Ursa Major II Dwarf
warp

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