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32-524: The Corona Borealis Supercluster is a supercluster located in the constellation Corona Borealis and the most prominent example of its kind in the Northern Celestial Hemisphere . Dense and compact compared with other superclusters, its mass has been calculated to lie somewhere between 0.6 and 12 × 10 solar masses (M⊙). It contains the galaxy clusters Abell 2056 , Abell 2061 , Abell 2065 (the most massive galaxy cluster within

64-446: A redshift of 0.07, which is equivalent to a distance of around 265.5 megaparsecs (964 million light-years). Astronomers C. Donald Shane and Carl A. Wirtanen were the first to note a concentration or "cloud" of "extragalactic nebulae" in the region during a large-scale survey of extragalactic structures in the sky. George Abell was the first to note the presence of what he called "second-order clusters", namely clusters of clusters in

96-408: A sense says that the universe is knowable and is playing fair with scientists. The cosmological principle depends on a definition of "observer", and contains an implicit qualification and two testable consequences. "Observers" means any observer at any location in the universe, not simply any human observer at any location on Earth: as Andrew Liddle puts it, "the cosmological principle [means that]

128-531: A velocity consistent with the value obtained from the dipole, indicating it is consistent with being entirely kinematic. Measurements of the velocity field of galaxies in the local universe show that on short scales galaxies are moving with the local group , and that the average mean velocity decreases with increasing distance. This follows the expectation if the CMB dipole were due to the local peculiar velocity field, it becomes more homogeneous on large scales. Surveys of

160-406: Is the notion that the spatial distribution of matter in the universe is uniformly isotropic and homogeneous when viewed on a large enough scale, since the forces are expected to act equally throughout the universe on a large scale, and should, therefore, produce no observable inequalities in the large-scale structuring over the course of evolution of the matter field that was initially laid down by

192-456: The Big Bang . Astronomer William Keel explains: The cosmological principle is usually stated formally as 'Viewed on a sufficiently large scale, the properties of the universe are the same for all observers.' This amounts to the strongly philosophical statement that the part of the universe which we can see is a fair sample, and that the same physical laws apply throughout. In essence, this in

224-490: The Planck Mission shows hemispheric bias in 2 respects: one with respect to average temperature (i.e. temperature fluctuations), the second with respect to larger variations in the degree of perturbations (i.e. densities), the collaboration noted that these features are not strongly statistically inconsistent with isotropy. Some authors say that the universe around Earth is isotropic at high significance by studies of

256-669: The cosmic microwave background temperature maps. There are however claims of isotropy violations from galaxy clusters , quasars , and type Ia supernovae . The cosmological principle implies that at a sufficiently large scale, the universe is homogeneous . Based on N-body simulations in a ΛCDM universe, Yadav and his colleagues showed that the spatial distribution of galaxies is statistically homogeneous if averaged over scales of 260 / h Mpc or more. A number of observations have been reported to be in conflict with predictions of maximal structure sizes: However, as pointed out by Seshadri Nadathur in 2013 using statistical properties,

288-449: The 1990s, observations assuming the cosmological principle have concluded that around 68% of the mass–energy density of the universe can be attributed to dark energy , which led to the development of the ΛCDM model . Observations show that more distant galaxies are closer together and have lower content of chemical elements heavier than lithium. Applying the cosmological principle, this suggests that heavier elements were not created in

320-514: The Big Bang but were produced by nucleosynthesis in giant stars and expelled across a series of supernovae and new star formation from the supernova remnants, which means heavier elements would accumulate over time. Another observation is that the furthest galaxies (earlier time) are often more fragmentary, interacting and unusually shaped than local galaxies (recent time), suggesting evolution in galaxy structure as well. A related implication of

352-413: The basic laws of physics. The two testable structural consequences of the cosmological principle are homogeneity and isotropy . Homogeneity means that the same observational evidence is available to observers at different locations in the universe ("the part of the universe which we can see is a fair sample"). Isotropy means that the same observational evidence is available by looking in any direction in

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384-536: The center of universe, Newton conceptualized the Earth as a sphere in orbital motion around the Sun within an empty space that extended uniformly in all directions to immeasurably large distances. He then showed, through a series of mathematical proofs on detailed observational data of the motions of planets and comets, that their motions could be explained by a single principle of " universal gravitation " that applied as well to

416-473: The correlation of distant effects with the dipole direction may indicate that its origin is not kinematic. Alternatively, Planck data has been used to estimate the velocity with respect to the CMB independently of the dipole, by measuring the subtle aberrations and distortions of fluctuations caused by relativistic beaming and separately using the Sunyaev-Zeldovich effect . These studies found

448-526: The cosmological principle exist in the universe and thus have called the ΛCDM model into question, with some authors suggesting that the cosmological principle is now obsolete and the Friedmann–Lemaître–Robertson–Walker metric breaks down in the late universe. The cosmic microwave background (CMB) is predicted by the ΛCDM model to be isotropic, that is to say that its intensity is about the same whichever direction we look at. Data from

480-413: The cosmological principle is that the largest discrete structures in the universe are in mechanical equilibrium . Homogeneity and isotropy of matter at the largest scales would suggest that the largest discrete structures are parts of a single indiscrete form, like the crumbs which make up the interior of a cake. At extreme cosmological distances, the property of mechanical equilibrium in surfaces lateral to

512-632: The dipole depends on the observing frequency showing that these anomalous features cannot be purely kinematic . Other authors have found radio dipoles consistent with the CMB expectation. Further claims of anisotropy along the CMB dipole axis have been made with respect to the Hubble diagram of type Ia supernovae and quasars . Separately, the CMB dipole direction has emerged as a preferred direction in some studies of alignments in quasar polarizations,   strong lensing time delay, type Ia supernovae, and standard candles . Some authors have argued that

544-468: The dipole is that it is due to the Doppler effect caused by the motion of the solar system with respect to the CMB rest-frame. Several studies have reported dipoles in the large scale distribution of galaxies that align with the CMB dipole direction, but indicate a larger amplitude than would be caused by the CMB dipole velocity. A similar dipole is seen in data of radio galaxies, however the amplitude of

576-478: The dynamics of a homogeneous isotropic universe. Independently, Georges Lemaître derived in 1927 the equations of an expanding universe from the General Relativity equations. Thus, a non-static universe is also implied, independent of observations of distant galaxies, as the result of applying the cosmological principle to general relativity . Karl Popper criticized the cosmological principle on

608-482: The existence of structures larger than the homogeneous scale (260 / h Mpc by Yadav's estimation) does not necessarily violate the cosmological principle in the ΛCDM model (see Huge-LQG § Dispute ). The cosmic microwave background (CMB) provides a snapshot of a largely isotropic and homogeneous universe. The largest scale feature of the CMB is the dipole anisotropy; it is typically subtracted from maps due to its large amplitude. The standard interpretation of

640-452: The first publication of his Abell catalogue in 1958. Postman and colleagues were the first to study the supercluster in detail in 1988, calculating it to have a mass of 8.2 × 10 solar masses , and contain the Abell clusters Abell 2061 , Abell 2065 , Abell 2067 , Abell 2079 , Abell 2089 , and Abell 2092 . Abell 2124 lies 33 megaparsecs (110 million light-years) from the centre of

672-452: The grounds that it makes "our lack of knowledge a principle of knowing something ". He summarized his position as: Although the universe is inhomogeneous at smaller scales, according to the ΛCDM model it ought to be isotropic and statistically homogeneous on scales larger than 250 million light years. However, recent findings (the Axis of Evil for example) have suggested that violations of

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704-681: The largest structures in the universe according to the Cosmological principle , larger structures have been observed in surveys, including the Sloan Great Wall . A 2014 study indicates that the Virgo Supercluster is only a lobe of an even greater supercluster, Laniakea. In 2014, the newly announced Laniakea Supercluster subsumed the Hydra-Centaurus Supercluster, which became a component of

736-686: The largest structures known to date. Observations of superclusters can give information about the initial condition of the universe, when these superclusters were created. The directions of the rotational axes of galaxies within superclusters are studied by those who believe that they may give insight and information into the early formation process of galaxies in the history of the Universe. Interspersed among superclusters are large voids of space where few galaxies exist. Superclusters are frequently subdivided into groups of clusters called galaxy groups and clusters . Although superclusters are supposed to be

768-462: The line of sight can be empirically tested; however, under the assumption of the cosmological principle, it cannot be detected parallel to the line of sight (see timeline of the universe ). Cosmologists agree that in accordance with observations of distant galaxies, a universe must be non-static if it follows the cosmological principle. In 1923, Alexander Friedmann set out a variant of Albert Einstein 's equations of general relativity that describe

800-407: The local volume have been used to reveal a low density region in the opposite direction to the CMB dipole, potentially explaining the origin of the local bulk flow . The perfect cosmological principle is an extension of the cosmological principle, and states that the universe is homogeneous and isotropic in space and time. In this view the universe looks the same everywhere (on the large scale),

832-488: The new supercluster. In 2014, the newly announced Laniakea Supercluster subsumed the Pavo-Indus Supercluster, which became a component of the new supercluster. Includes Fornax Cluster (S373), Dorado and Eridanus clouds. Length = 652 Million light-years z =1.1 Length=70Mpc z =0.42 Length=6Mpc Cosmological principle In modern physical cosmology , the cosmological principle

864-583: The orbits of the Galilean moons around Jupiter, the Moon around the Earth, the Earth around the Sun, and to falling bodies on Earth. That is, he asserted the equivalent material nature of all bodies within the Solar System, the identical nature of the Sun and distant stars and thus the uniform extension of the physical laws of motion to a great distance beyond the observational location of Earth itself. Since

896-585: The supercluster and has been considered part of the group by some authors. Abell 2069 lies close by but is more distant, with a line-of-sight association only. Supercluster The existence of superclusters indicates that the galaxies in the Universe are not uniformly distributed; most of them are drawn together in groups and clusters, with groups containing up to some dozens of galaxies and clusters up to several thousand galaxies. Those groups and clusters and additional isolated galaxies in turn form even larger structures called superclusters. Their existence

928-486: The supercluster), Abell 2067 , Abell 2079 , Abell 2089 , and Abell 2092 . Of these, Abell 2056, 2061, 2065, 2067 and A2089 are gravitationally bound and in the process of collapsing to form a massive cluster. This entity has an estimated mass of around 1 × 10 M⊙. If there is inter-cluster mass present, then Abell 2092 may also be involved. It has been estimated to be 100 megaparsecs (330 million light-years ) wide and 40 megaparsecs (130 million light years) deep. It has

960-558: The universe ("the same physical laws apply throughout"). The principles are distinct but closely related, because a universe that appears isotropic from any two (for a spherical geometry, three) locations must also be homogeneous. The cosmological principle is first clearly asserted in the Philosophiæ Naturalis Principia Mathematica (1687) of Isaac Newton . In contrast to some earlier classical or medieval cosmologies, in which Earth rested at

992-488: The universe looks the same whoever and wherever you are." The qualification is that variation in physical structures can be overlooked, provided this does not imperil the uniformity of conclusions drawn from observation: the Sun is different from the Earth, our galaxy is different from a black hole, some galaxies advance toward rather than recede from us, and the universe has a "foamy" texture of galaxy clusters and voids, but none of these different structures appears to violate

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1024-423: Was first postulated by George Abell in his 1958 Abell catalogue of galaxy clusters. He called them "second-order clusters", or clusters of clusters. Superclusters form massive structures of galaxies, called "filaments" , "supercluster complexes", "walls" or "sheets", that may span between several hundred million light-years to 10 billion light-years, covering more than 5% of the observable universe . These are

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