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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, based on data from the Sloan Digital Sky Survey. Size The wall measures in length, located approximately one billion light-years away. In the sky, it is located within the region of the constellations Corvus, Hydra and Centaurus. It is approximately 1/60 of the diameter of the observable universe, making it the sixth largest known object after the large quasar groups Clowes-Campusano LQG, U1.11, Huge-LQG, the Giant GRB Ring and the galaxy filament Hercules–Corona Borealis Great Wall (Her-CrB GW), respectively. The Sloan Great Wall is between 1.8–2.7 times longer than the CfA2 Great Wall of galaxies (discovered by Margaret Geller and John Huchra of Harvard in 1989). It also contains several galactic supercluster A superclus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 by a team of American astronomers led by Margaret J. Geller and John Huchra while analyzing data gathered by the second CfA Redshift Survey of the Center for Astrophysics Harvard & Smithsonian (CfA). Characteristics The term "Great" has been added to distinguish it as an even larger type compared to standard galaxy walls. Great walls are so rare that only five or possibly six (if the disputed Hercules–Corona Borealis Great Wall is counted) of them have been discovered to date. The CfA2 Great Wall has the maximum dimensions of either 500 million or 750 million light years depending on the figure and the reference used. It is 200 million light years in width and about 16 million light years in thickness. Its nearest point is about 30 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Largest Known 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 filaments and large quasar groups (LQGs). The list characterizes each structure based on its longest dimension. Note that this list refers only to coupling of matter with defined limits, and not the coupling of matter in general (as per example the cosmic microwave background, which fills the entire universe). All structures in this list are defined as to whether their presiding limits have been identified. There are some speculations about this list: *The Zone of Avoidance, or the part of the sky occupied by the Milky Way, blocks out light to several structures, making their limits imprecisely identified. *Some structures are far too distant to be seen even with the most powerful telescopes. Some factors are included to explain the st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxy Filaments
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 superclusters. These massive, thread-like formations can reach 80 megaparsecs ''h''−1 (or of the order of 160 to 260 million light-years) and form the boundaries between large voids. Formation In the standard model 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 matte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monthly Notices Of The Royal Astronomical Society
''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes letters and papers reporting original research in relevant fields. Despite the name, the journal is no longer monthly, nor does it carry the notices of the Royal Astronomical Society. History The first issue of MNRAS was published on 9 February 1827 as ''Monthly Notices of the Astronomical Society of London'' and it has been in continuous publication ever since. It took its current name from the second volume, after the Astronomical Society of London became the Royal Astronomical Society (RAS). Until 1960 it carried the monthly notices of the RAS, at which time these were transferred to the newly established ''Quarterly Journal of the Royal Astronomical Society'' (1960–1996) and then to its successor journal ''Astronomy & Geophysics'' (since 1997). Until 1965, MNRAS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 is part of the Virgo Supercluster, which is part of the Laniakea Supercluster."Earth's new address: 'Solar System, Milky Way, Laniakea ''Nature (journal), Nature'' The large size and low density of superclusters means that they, unlike clusters, expand with the Hubble expansion. The number of superclusters in the observable universe is estimated to be 10 million. Existence [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher learning in the United States and one of the most prestigious and highly ranked universities in the world. The university is composed of ten academic faculties plus Harvard Radcliffe Institute. The Faculty of Arts and Sciences offers study in a wide range of undergraduate and graduate academic disciplines, and other faculties offer only graduate degrees, including professional degrees. Harvard has three main campuses: the Cambridge campus centered on Harvard Yard; an adjoining campus immediately across Charles River in the Allston neighborhood of Boston; and the medical campus in Boston's Longwood Medical Area. Harvard's endowment is valued at $50.9 billion, making it the wealthiest academic institution in the world. Endowment inco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Huchra
John Peter Huchra ( ; December 23, 1948 – October 8, 2010) was an American astronomer and professor. He was the Vice Provost for Research Policy at Harvard University and a Professor of Astronomy at the Center for Astrophysics Harvard & Smithsonian.AAS Officers [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Margaret Geller
Margaret J. Geller (born December 8, 1947) is an American astrophysicist at the Center for Astrophysics Harvard & Smithsonian. Her work has included pioneering maps of the nearby universe, studies of the relationship between galaxies and their environment, and the development and application of methods for measuring the distribution of matter in the universe. Career Geller made pioneering maps of large-scale structure in the universe. Geller received a Bachelor of Arts degree in Physics at the University of California, Berkeley (1970) and a Ph.D. in Physics from Princeton (1974). Geller completed her doctoral dissertation, titled "Bright galaxies in rich clusters: a statistical model for magnitude distributions", under the supervision of James Peebles. Although Geller was thinking about studying solid state physics in graduate school, Charles Kittel suggested she go to Princeton to study astrophysics. After research fellowships at the Center for Astrophysics Harvard & Smith ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hercules–Corona Borealis Great Wall
The Hercules–Corona Borealis Great Wall or simply the Great Wall is the largest known structure in the observable universe, measuring approximately 10 billion light-years in length (the observable universe is about 93 billion light-years in diameter). This massive superstructure is a region of the sky seen in the data set mapping of gamma-ray bursts (GRBs) that has been found to have an unusually higher concentration of similarly distanced GRBs than the expected average distribution. It was discovered in early November 2013 by a team of American and Hungarian astronomers led by István Horváth, Jon Hakkila and Zsolt Bagoly while analyzing data from the Swift Gamma-Ray Burst Mission, together with other data from ground-based telescopes. It is the largest known formation in the universe, exceeding the size of the prior Huge-LQG by about two times. The overdensity lies at the Second, Third and Fourth Galactic Quadrants (NQ2, NQ3 and NQ4) of the sky. Thus, it lies in the Northe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant GRB Ring
The Giant GRB Ring is a ring of 9 gamma-ray bursts (GRBs) that may be associated with one of the largest known cosmic structures. It was discovered in July 2015 by a team of Hungarian and American astronomers led by L.G. Balazs while analyzing data from different gamma-ray and X-ray telescopes, in particular the Swift Spacecraft. The ring of GRBs lies at a distance of about 2.8 gigaparsecs (9.1 billion light years) from Earth at the redshift between 0.78 and 0.86 and measures about 1.72 gigaparsecs (5.6 billion light years) in diameter, making it one of the largest structures known. Typically, the distribution of GRBs in the universe appears in the sets of less than the 2σ distribution, or with fewer than two GRBs in the average data of the point-radius system. Thus, such a concentration as this appears extremely unlikely, given accepted theoretical models. Proposals include the existence of a giant supergalactic structure. This would be an extremely huge structure of the univer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huge-LQG
The Huge Large Quasar Group, (Huge-LQG, also called U1.27) is a possible structure or pseudo-structure of 73 quasars, referred to as a large quasar group, that measures about 4 billion light-years across. At its discovery, it was identified as the largest and the most massive known structure in the observable universe, though it has been superseded by the Hercules–Corona Borealis Great Wall at 10 billion light-years. There are also issues about its structure (see ''Dispute'' section below). Discovery Roger G. Clowes, together with colleagues from the University of Central Lancashire in Preston, United Kingdom, had reported on January 11, 2013 a grouping of quasars within the vicinity of the constellation Leo. They used data from the DR7QSO catalogue of the comprehensive Sloan Digital Sky Survey, a major multi-imaging and spectroscopic redshift survey of the sky. They reported that the grouping was, as they announced, the largest known structure in the observable univer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
