Void galaxy

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A void galaxy is a galaxy located in a cosmological void. [1] Few galaxies exist in voids; most are located in sheets, walls and filaments that surround voids and supervoids. [2] [3] Many void galaxies are connected through void filaments [4] or tendrils, [5] less massive versions of the regular galaxy filaments that surround voids. These filaments are often straighter than their non-void counterparts due to the lack of influence by surrounding filaments. [4] These filaments can even be rich enough to form poor galaxy clusters. [6] The void galaxies themselves are thought to represent pristine examples of galactic evolution, having few neighbours, and likely to have formed from pure intergalactic gas. [7]

Contents

Formation

It is theorised by many astrophysicists that void galaxies are the result of large galactic filaments being pulled by the gravity of a major super cluster out of the less densely populated areas, causing voids such as the Boötes Void to grow. Galaxies such as MCG+01-02-015 are sometimes left behind from such events. [8]

List of void galaxies

GalaxyVoidFilamentNotesComments
PC 1357+4641 Boötes Void [9] Emission-line galaxy
IRAS 14288+5255 [9] AGN X-ray source
G 1432+5302 [10] Starburst galaxy
G 1458+4944 [10] LINER galaxy
G 1507+4554 [10] Starburst galaxy
G 1510+4727A & G 1510+4727B [10] Interacting galaxy pair
BHI 1514+3819 [9]
FSS 1515+3823 [9]
G 1517+3949 [10] Starburst galaxy
G 1517+3956A & G 1517+3956B [10] Interacting galaxy pair
IRAS 15195+5050 [9] AGN X-ray source
Markarian 845 [9] Seyfert 1 (X-ray source)
CG 547 [9] Emission-line Galaxy
CG 637 [9]
CG 922 [9]
MCG+01-02-015 [11] [12] [13] [14] LEDA 1852 (Pisces)
Pisces A Local Void [15]
Pisces B [15]
NGC 7077 [16]
NGC 6503
NGC 6789

See also

Related Research Articles

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