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Abell 2147
Abell 2147 is a galaxy cluster in the Abell catalogue. , Archive of Chandra Cluster Entropy Tables, Michigan State University, retrieved 2012-03-31. It is located within the core of the Hercules Superclusters (SCI 160), within Serpens Caput, near the cluster , approximately two degrees south southwest of the Hercules Cluster
The Hercules Cluster ( Abel ...
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Abell Catalogue
The Abell catalog of rich clusters of galaxies is an all-sky catalog of 4,073 rich galaxy clusters of nominal redshift ''z'' ≤ 0.2. This catalog supplements a revision of George O. Abell's original "Northern Survey" of 1958, which had only 2,712 clusters, with a further 1,361 clustersthe "Southern Survey" of 1989, published after Abell's death by co-authors Harold G. Corwin and Ronald P. Olowin from those parts of the south celestial hemisphere that had been omitted from the earlier survey. The Abell catalog, and especially its clusters, are of interest to amateur astronomers as challenge objects to be viewed in dark locations on large aperture amateur telescopes. The Northern Survey The original catalog of 2,712 rich clusters of galaxies was published in 1958 by George O. Abell (1927–1983), who was then studying at the California Institute of Technology. The catalog, which formed part of Abell's PhD thesis, was prepared by means of a visual inspection of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoch (astronomy)
In astronomy, an epoch or reference epoch is a moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a celestial body, as they are subject to perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodies) can be used to generate an ephemeris, a table of values giving the posit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virgo (constellation)
Virgo is one of the constellations of the zodiac. Its name is Latin for maiden, and its old astronomical symbol is (♍︎). Lying between Leo (constellation), Leo to the west and Libra (constellation), Libra to the east, it is the second-largest constellation in the sky (after Hydra (constellation), Hydra) and the largest constellation in the zodiac. The ecliptic intersects the celestial equator within this constellation and Pisces (constellation), Pisces. Underlying these technical two definitions, the sun passes directly overhead of the equator, within this constellation, at the September equinox. Virgo can be easily found through its brightest star, Spica. Location Virgo is prominent in the spring sky in the Northern Hemisphere, visible all night in March and April. As the largest zodiac constellation, the Sun takes 44 days to pass through it, longer than any other. From 1990 and until 2062, this will take place from September 16 to October 30. It is located in the third ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Volt
In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy gained by a single electron accelerating from rest through an electric potential difference of one volt in vacuum. When used as a unit of energy, the numerical value of 1 eV in joules (symbol J) is equivalent to the numerical value of the charge of an electron in coulombs (symbol C). Under the 2019 redefinition of the SI base units, this sets 1 eV equal to the exact value Historically, the electronvolt was devised as a standard unit of measure through its usefulness in electrostatic particle accelerator sciences, because a particle with electric charge ''q'' gains an energy after passing through a voltage of ''V.'' Since ''q'' must be an integer multiple of the elementary charge ''e'' for any isolated particle, the gained energy in units of electronvolts conveniently equals that integer times the voltage. It is a common unit of energy within p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxy Cluster
A galaxy cluster, or a cluster of galaxies, is a structure that consists of anywhere from hundreds to thousands of galaxies that are bound together by gravity, with typical masses ranging from 1014 to 1015 solar masses. They are the second-largest known gravitationally bound structures in the universe after galaxy filaments and were believed to be the largest known structures in the universe until the 1980s, when superclusters were discovered. One of the key features of clusters is the intracluster medium (ICM). The ICM consists of heated gas between the galaxies and has a peak temperature between 2–15 keV that is dependent on the total mass of the cluster. Galaxy clusters should not be confused with ''galactic clusters'' (also known as open clusters), which are star clusters ''within'' galaxies, or with globular clusters, which typically orbit galaxies. Small aggregates of galaxies are referred to as galaxy groups rather than clusters of galaxies. The galaxy groups and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hercules Superclusters
The Hercules Superclusters (SCl 160) refers to a set of two nearby superclusters of galaxies. Relative to other local superclusters, Hercules is considered particularly large, being approximately 330 Mly in diameter. The Northern Local Supervoid lies in front of the superclusters, and is as big as the superclusters themselves. The redshifts of the member galaxies lie between 0.0304 and 0.0414. The region includes Abell 2147, Abell 2151 (Hercules Cluster), and Abell 2152 galaxy clusters. An extremely long filament of galaxies has been found, that connects this group of clusters to the Abell 2197 and Abell 2199 pair. Abell 2162 in the nearby constellation Corona Borealis is also a member. The Hercules Superclusters are near the Coma Supercluster, helping make up part of the CfA2 Great Wall. In the 1930s, Harlow Shapley studied the structure of the distribution of galaxies in the constellation of Hercules, and was probably first to discover the existence of a supercluster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serpens Caput
Serpens ( grc, , , the Serpent) is a constellation in the northern celestial hemisphere. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the IAU designated constellations, 88 modern constellations designated by the International Astronomical Union. It is unique among the modern constellations in being split into two non-contiguous parts, Serpens Caput (Serpent Head) to the west and Serpens Cauda (Serpent Tail) to the east. Between these two halves lies the constellation of Ophiuchus, the "Serpent-Bearer". In figurative representations, the body of the serpent is represented as passing behind Ophiuchus between Mu Serpentis in ''Serpens Caput'' and Nu Serpentis in ''Serpens Cauda''. The brightest List of stars in Serpens, star in Serpens is the red giant star Alpha Serpentis, or Unukalhai, in Serpens Caput, with an apparent magnitude of 2.63. Also located in Serpens Caput are the naked-eye globular cluster Messier 5 and the naked-eye v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abell 2152
Abell 2152 is a bimodal galaxy cluster and one of three clusters comprising the Hercules Supercluster. It contains 3 BCGs; the S0 lenticular UGC 10204, the pair UGC 10187, and the SA0 unbarred lenticular CGCG 108-083. In total there are 41 galaxies which are confirmed to be members of the cluster. The cluster is classified as a Bautz-Morgan type III and Rood-Sastry class F cluster, indicating morphological irregularity and perhaps dynamical youth. It is receding from the Milky Way galaxy with a velocity of 12385 km/s. Abell 2152 is the nearest cluster in which significant gravitational lensing of a background source has been observed. The arc-like background galaxy, known as J160529.52+162633.9, lies at a redshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ... z=0.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hercules Cluster
The Hercules Cluster ( Abell 2151) is a cluster of about 200 galaxies some 500 million light-years distant in the constellation Hercules. It is rich in spiral galaxies and shows many interacting galaxies. The cluster is part of the larger Hercules Supercluster, which is itself part of the much larger Great Wall super-structure. The cluster's brightest member is the giant elliptical galaxy NGC 6041. See also * Abell catalogue * List of Abell clusters * X-ray Astronomy External links * *Hercules Cluster— University of Alabama The University of Alabama (informally known as Alabama, UA, or Bama) is a Public university, public research university in Tuscaloosa, Alabama. Established in 1820 and opened to students in 1831, the University of Alabama is the oldest and la ... * References 2151 Hercules Superclusters Abell richness class 2 Galaxy clusters {{galaxy-cluster-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Abell Clusters
The Abell catalogue is a catalogue of approximately 4,000 galaxy clusters with at least 30 members, almost complete to a redshift of ''z'' = 0.2. It was originally compiled by the American astronomer George O. Abell in 1958 using plates from POSS, and extended to the southern hemisphere by Abell, Corwin and Olowin in 1987. The name "Abell" is also commonly used as a designation for objects he compiled in a catalogue of 86 planetary nebulae in 1966. The proper designation for the galaxy clusters is ACO, as in "ACO 13", while the planetary-nebula designation is the single letter A, as in "A 39". 1–1999 2000–4076 Southern catalogue S1–S1174 See also * Lists of astronomical objects * 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 eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chandra X-ray Observatory
The Chandra X-ray Observatory (CXO), previously known as the Advanced X-ray Astrophysics Facility (AXAF), is a Flagship-class space telescope launched aboard the during STS-93 by NASA on July 23, 1999. Chandra is sensitive to X-ray sources 100 times fainter than any previous X-ray telescope, enabled by the high angular resolution of its mirrors. Since the Earth's atmosphere absorbs the vast majority of X-rays, they are not detectable from Earth-based telescopes; therefore space-based telescopes are required to make these observations. Chandra is an Earth satellite in a 64-hour orbit, and its mission is ongoing . Chandra is one of the Great Observatories, along with the Hubble Space Telescope, Compton Gamma Ray Observatory (1991–2000), and the Spitzer Space Telescope (2003–2020). The telescope is named after the Nobel Prize-winning Indian-American astrophysicist Subrahmanyan Chandrasekhar. Its mission is similar to that of ESA's XMM-Newton spacecraft, also launched in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
