In
cosmology, galaxy filaments (subtypes: supercluster complexes, galaxy walls, and galaxy sheets)
[ Boris V. Komberg, Andrey V. Kravtsov, Vladimir N. Lukash; "The search and investigation of the Large Groups of Quasars" ; ;][R.G. Clowes; "Large Quasar Groups - A Short Review"; ''The New Era of Wide Field Astronomy'', ASP Conference Series, vol. 232.; 2001; Astronomical Society of the Pacific; ; ] are the largest known structures in the
universe, consisting of walls of gravitationally bound galaxy
supercluster
A supercluster is a large group of smaller galaxy clusters or galaxy groups; they are among the largest known structures in the universe. The Milky Way is part of the Local Group galaxy group (which contains more than 54 galaxies), which in turn ...
s. These massive, thread-like formations can reach 80
megaparsecs ''h''−1 (or of the order of 160 to 260 million
light-year
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...
s) and form the boundaries between large
voids
Void may refer to:
Science, engineering, and technology
* Void (astronomy), the spaces between galaxy filaments that contain no galaxies
* Void (composites), a pore that remains unoccupied in a composite material
* Void, synonym for vacuum, a s ...
.
Formation
In the
standard model
The Standard Model of particle physics is the theory describing three of the four known fundamental forces (electromagnetism, electromagnetic, weak interaction, weak and strong interactions - excluding gravity) in the universe and classifying a ...
of the evolution of the universe, galactic filaments form along and follow web-like strings of
dark matter—also referred to as the galactic web or cosmic web. It is thought that this dark matter dictates the structure of the Universe on the grandest of scales. Dark matter gravitationally attracts
baryonic matter, and it is this "normal" matter that astronomers see forming long, thin walls of super-galactic clusters.
Discovery
Discovery of structures larger than superclusters began in the late-1980s. In 1987, astronomer
R. Brent Tully
Richard Brent Tully (born March 9, 1943) is a Canadian-born American astronomer at the Institute for Astronomy in Honolulu, Hawaii.
Born in Toronto, Ontario, and raised in Vancouver, British Columbia, Tully's specialty is the astrophysics of gal ...
of the
University of Hawaii's Institute of Astronomy identified what he called the
Pisces–Cetus Supercluster Complex
The Pisces–Cetus Supercluster Complex is a galaxy filament. It includes the Laniakea Supercluster which contains the Virgo Supercluster lobe which in turn contains the Local Group, the galaxy cluster that includes the Milky Way.
This filament ...
. In 1989, the
CfA2 Great Wall
The Great Wall (also called Coma Wall), sometimes specifically referred to as the CfA2 Great Wall, is an immense galaxy filament. It is one of the largest known superstructures in the observable universe.
This structure was discovered c. 1989 ...
was discovered, followed by the
Sloan Great Wall
The Sloan Great Wall (SGW) is a cosmic structure formed by a giant wall of galaxies (a galaxy filament). Its discovery was announced from Princeton University on October 20, 2003, by J. Richard Gott III, Mario Jurić, and their colleagues, b ...
in 2003. On January 11, 2013, researchers led by Roger Clowes of the
University of Central Lancashire
, mottoeng = "From the Earth to the Sun"
, established = as Institution for the Diffusion of Useful Knowledgere-established 1992 (University status granted)
, type = Public
, chancellor ...
announced the discovery of a
large quasar group
A large quasar group (LQG) is a collection of quasars (a form of supermassive black hole active galactic nuclei) that form what are thought to constitute the largest astronomical structures in the observable universe. LQGs are thought to be prec ...
, the
Huge-LQG, which dwarfs previously discovered galaxy filaments in size. In November 2013, using
gamma-ray bursts as reference points, astronomers discovered the
Hercules–Corona Borealis Great Wall, an extremely huge filament measuring more than 10 billion light-years across.
Filaments
Filament subtype of filaments have roughly similar major and minor axes in cross-section, along the lengthwise axis.
* A short filament, detected by identifying an alignment of star-forming galaxies, in the neighborhood of the
Milky Way and the
Local Group was proposed by Adi Zitrin and
Noah Brosch
Noah Brosch (born 1948) is an Israeli astronomer, astrophysicist and space researcher.
Biography
Noah Brosch was born in Bucharest (Romania) in 1948 and immigrated with his family to Israel in 1963.
Brosch studied at Tel Aviv University (BSc ...
. The reality of this filament, and the identification of a similar but shorter filament, were the result of a study by McQuinn ''et al.'' (2014) based on distance measurements using the TRGB method.
Galaxy walls
The galaxy wall subtype of filaments have a significantly greater major axis than minor axis in cross-section, along the lengthwise axis.
* A "Centaurus Great Wall" (or "Fornax Great Wall" or "Virgo Great Wall") has been proposed, which would include the
Fornax Wall The Fornax Wall is a superstructure known as a galaxy filament or galaxy wall. It is a long filament of galaxies with a major axis longer than its minor one. The filament contains not only Dorado Group but also the Fornax cluster
The Fornax Clus ...
as a portion of it (visually created by the
Zone of Avoidance
The Zone of Avoidance (ZOA, ZoA), or Zone of Galactic Obscuration (ZGO), is the area of the sky that is obscured by the Milky Way.
The Zone of Avoidance was originally called the Zone of Few Nebulae in an 1878 paper by English astronomer Richard ...
) along with the
Centaurus Supercluster and the
Virgo Supercluster also known as our
Local Supercluster within which the Milky Way galaxy is located (implying this to be the
Local Great Wall
Local may refer to:
Geography and transportation
* Local (train), a train serving local traffic demand
* Local, Missouri, a community in the United States
* Local government, a form of public administration, usually the lowest tier of administrat ...
).
* A wall was proposed to be the physical embodiment of the
Great Attractor, with the
Norma Cluster as part of it. It is sometimes referred to as the
Great Attractor Wall
Great may refer to: Descriptions or measurements
* Great, a relative measurement in physical space, see Size
* Greatness, being divine, majestic, superior, majestic, or transcendent
People
* List of people known as "the Great"
*Artel Great (born ...
or
Norma Wall Norma may refer to:
* Norma (given name), a given name (including a list of people with the name)
Astronomy
*Norma (constellation)
* 555 Norma, a minor asteroid
*Cygnus Arm or Norma Arm, a spiral arm in the Milky Way galaxy
Geography
*Norma, Lazi ...
. This suggestion was superseded by the proposal of a supercluster,
Laniakea, that would encompass the Great Attractor, Virgo Supercluster, Hydra-Centaurus Superclusters.
* A wall was proposed in 2000 to lie at z=1.47 in the vicinity of radio galaxy
B3 0003+387
B3, B03, B.III or B-3 may refer to:
Military
American bombers
* Keystone B-3, a biplane bomber of the United States Army Air Corps
* Next-Generation Bomber (2018 Bomber), next bomber follow-on to the B-2 stealth bomber program
* Long Range Strik ...
.
* A wall was proposed in 2000 to lie at z=0.559 in the northern
Hubble Deep Field (HDF North).
Map of nearest galaxy walls
Large Quasar Groups
Large quasar group
A large quasar group (LQG) is a collection of quasars (a form of supermassive black hole active galactic nuclei) that form what are thought to constitute the largest astronomical structures in the observable universe. LQGs are thought to be prec ...
s (LQGs) are some of the largest structures known.
[ They are theorized to be protohyperclusters/proto-supercluster-complexes/galaxy filament precursors.]
Supercluster complex
Maps of large-scale distribution
File:Superclusters atlasoftheuniverse.gif, The universe within 1 billion light-years (307 Mpc) of Earth, showing local supercluster
A supercluster is a large group of smaller galaxy clusters or galaxy groups; they are among the largest known structures in the universe. The Milky Way is part of the Local Group galaxy group (which contains more than 54 galaxies), which in turn ...
s forming filaments and voids
File:Nearsc.gif, Map of nearest walls, voids and superclusters
File:2dfdtfe.gif, 2dF survey map, containing the SDSS Great Wall
File:2MASS LSS chart-NEW Nasa.jpg, 2MASS XSC infrared sky map
See also
* List of largest cosmic structures
This is a list of the largest cosmic structures so far discovered. The unit of measurement used is the light-year (distance traveled by light in one Julian year; approximately 9.46 trillion kilometres).
This list includes superclusters, galaxy ...
* Galaxy
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. ...
* Galaxy cluster
* Galaxy supercluster
A supercluster is a large group of smaller galaxy clusters or galaxy groups; they are among the largest known structures in the universe. The Milky Way is part of the Local Group galaxy group (which contains more than 54 galaxies), which in turn ...
* Illustris project
The Illustris project was a series of astrophysical simulations run by an international collaboration of scientists. The aim was to study the processes of galaxy formation and evolution in the universe with a comprehensive physical model. Early r ...
* Large-scale structure
* List of galaxies
* List of galaxy groups and clusters
This article lists some galaxy groups and galaxy clusters.
Defining the limits of galaxy clusters is imprecise as many clusters are still forming. In particular, clusters close to the Milky Way tend to be classified as galaxy clusters even whe ...
* Void (astronomy)
References
Further reading
* Kevin A. Pimbblet, , arXiv, 14 March 2005.
*
External links
Pictures of the filamentary network
{{Portal bar, Stars, Spaceflight, Outer space, Solar System, Science
Large-scale structure of the cosmos