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List Of Black Holes
This list of black holes (and stars considered probable candidates) is organized by mass (including black holes of undetermined mass); some items in this list are galaxies or star clusters that are believed to be organized around a black hole. Messier and New General Catalogue designations are given where possible. Supermassive black holes and candidates * 1ES 2344+514 * Ton 618 (this quasar has possibly the biggest black hole ever found, estimated at 66 billion solar masses) * 3C 371 * 4C +37.11 (this radio galaxy is believed to have binary supermassive black holes) * AP Lib * S5 0014+81 (said to be a compact hyperluminous quasar, estimated at 40 billion solar masses) 17:53:24 GMT. * APM 08279+5255 (contains one of the largest black holes, estimated at 10-23 billion solar masses; previous candidate for largest) * Arp 220 * Centaurus A * Fornax A * HE0450-2958 * IC 1459 * Messier 31 (or the Andromeda Galaxy) * Messier 32 * Messier 51 (or the Whirlpool Galaxy) * Messier 60 * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Hole
A black hole is a region of spacetime where gravitation, gravity is so strong that nothing, including light or other Electromagnetic radiation, electromagnetic waves, has enough energy to escape it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary (topology), boundary of no escape is called the event horizon. Although it has a great effect on the fate and circumstances of an object crossing it, it has no locally detectable features according to general relativity. In many ways, a black hole acts like an ideal black body, as it reflects no light. Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with thermal radiation, the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is of the order of billionths of a kelvin for stellar black holes, making it essentially impossible to observe directly. Obje ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomy And Astrophysics
''Astronomy & Astrophysics'' is a monthly peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics. The journal is run by a Board of Directors representing 27 sponsoring countries plus a representative of the European Southern Observatory. The journal is published by EDP Sciences and the editor-in-chief is . History Origins ''Astronomy and Astrophysics'' (A&A) was created as an answer to the publishing scenario found in Europe in the 1960s. At that time, multiple journals were being published in several countries around the continent. These journals usually had a limited number of subscribers, and published articles in languages other than English, resulting in a small number of citations compared to American and British journals. Starting in 1963, conversations between astronomers from European countries assessed the need for a common astronomical journal. On 8 April 1968, leading astronomers from Belgium, Denmark, Fran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 81
Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a grand design spiral galaxy about 12 million light-years away in the constellation Ursa Major. It has a D25 isophotal diameter of . Because of its relative proximity to the Milky Way galaxy, large size, and active galactic nucleus (which harbors a 70 million supermassive black hole), Messier 81 has been studied extensively by professional astronomers. The galaxy's large size and relatively high brightness also makes it a popular target for amateur astronomers. In late February 2022, astronomers reported that M81 may be the source of FRB 20200120E, a repeating fast radio burst. Discovery Messier 81 was first discovered by Johann Elert Bode on 31 December 1774. Thus, it is sometimes referred to as "Bode's Galaxy". In 1779, Pierre Méchain and Charles Messier reidentified Bode's object, hence listed it in the Messier Catalogue. Visibility The galaxy is to be found approximately 10° northwest of Alpha Ursae M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 77
Messier 77 or M77, also known as NGC 1068 and the Squid Galaxy, is a barred spiral galaxy about 47 million light-years away in the constellation Cetus. Messier 77 was discovered by Pierre Méchain in 1780, who originally described it as a nebula. Méchain then communicated his discovery to Charles Messier, who subsequently listed the object in his catalog. Both Messier and William Herschel described this galaxy as a star cluster. Today, however, the object is known to be a galaxy. The morphological classification of NGC 1068 in the De Vaucouleurs system is (R)SA(rs)b, where the '(R)' indicates an outer ring-like structure, 'SA' denotes a non-barred spiral, '(rs)' means a transitional inner ring/spiral structure, and 'b' says the spiral arms are moderately wound. Ann et al. (2015) gave it a class of SAa, suggesting tightly wound arms. However, infrared images of the inner part of the galaxy reveal a prominent bar not seen in visual light, and for this reason it is now conside ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 60
Messier 60 or M60, also known as NGC 4649, is an elliptical galaxy approximately 57 million light-years away in the equatorial constellation of Virgo. Together with NGC 4647, it forms a pair known as Arp 116. Messier 60 and nearby elliptical galaxy Messier 59 were discovered by Johann Gottfried Koehler in April 1779, observing a comet in the same part of the sky. Charles Messier added both to his catalogue about three days after this. Characteristics This is an elliptical galaxy of type E (E1.5), although some sources class it as S0 – a lenticular galaxy. An E2 class indicates a flattening of 20%, which has a nearly round appearance. The isophotes of the galaxy are boxy in shape, rather than simple ellipses. The mass-to-light ratio is a near constant 9.5 in the V (visual) band of the UBV system. The galaxy has an effective radius of (translating, at its distance, to about 10 kpc), with an estimated mass of ~1012 within a threefold volume, of which near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whirlpool Galaxy
The Whirlpool Galaxy, also known as Messier 51a, M51a, and NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus. It lies in the constellation Canes Venatici, and was the first galaxy to be classified as a spiral galaxy. Its distance is 31 million light-years from Earth. The galaxy and its companion, NGC 5195, are easily observed by amateur astronomers, and the two galaxies may be seen with binoculars. The Whirlpool Galaxy has been extensively observed by professional astronomers, who study it to understand galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions. Discovery What later became known as the Whirlpool Galaxy was discovered on October 13, 1773, by Charles Messier while hunting for objects that could confuse comet hunters, and was designated in Messier's catalogue as M51. Its companion galaxy, NGC 5195, was discovered in 1781 by Pierre Méchain, although it was not known wheth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 51
Messier may refer to: People with the surname *Charles Messier, French astronomer *Éric Messier, former NHL defenseman *George Messier, French inventor *Jean-Marie Messier, former CEO of Vivendi Universal *Marc Messier, Canadian actor from Quebec *Mark Messier, former NHL player, Hall of fame class 2007 *Paul Arthur Messier, art conservator Other uses *Messier object, a set of 110 astronomical objects *Messier (crater) *Messier (automobile) Messier was a French automobile manufacturer, based at Montrouge, on the southern edge of Paris, from 1925 till 1931.Linz, Schrader: ''Die Internationale Automobil-Enzyklopädie.''Georgano: ''The Beaulieu Encyclopedia of the Automobile.''Georgan ..., a French car produced 1925–1931 * Messier-Dowty and preceding companies in manufacture of aircraft undercarriage {{disambiguation, surname French-language surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 32
Messier 32 (also known as M32 and NGC 221) is a dwarf "early-type" galaxy about from the Solar System, appearing in the constellation Andromeda. M32 is a satellite galaxy of the Andromeda Galaxy (M31) and was discovered by Guillaume Le Gentil in 1749. The galaxy is a prototype of the relatively rare compact elliptical (cE) class. Half the stars concentrate within an effective radius (inner core) of . Densities in the central stellar cusp increase steeply, exceeding 3×107 (that is, 30 million) pc−3 (that is, per parsec cubed) at the smallest sub-radii resolved by HST, and the half-light radius of this central star cluster is around . Like more ordinary elliptical galaxies, M32 contains mostly older faint red and yellow stars with practically no dust or gas and consequently no current star formation. It does, however, show hints of star formation in the relatively recent past. Origins The structure and stellar content of M32 are difficult to explain by traditional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andromeda Galaxy
The Andromeda Galaxy (IPA: ), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula, is a barred spiral galaxy with the diameter of about approximately from Earth and the nearest large galaxy to the Milky Way. The galaxy's name stems from the area of Earth's sky in which it appears, the constellation of Andromeda, which itself is named after the princess who was the wife of Perseus in Greek mythology. The virial mass of the Andromeda Galaxy is of the same order of magnitude as that of the Milky Way, at . The mass of either galaxy is difficult to estimate with any accuracy, but it was long thought that the Andromeda Galaxy is more massive than the Milky Way by a margin of some 25% to 50%. This has been called into question by a 2018 study that cited a lower estimate on the mass of the Andromeda Galaxy, combined with preliminary reports on a 2019 study estimating a higher mass of the Milky Way. The Andromeda Galaxy has a diameter of about , making it the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 31
Messier may refer to: People with the surname *Charles Messier, French astronomer *Éric Messier, former NHL defenseman *George Messier, French inventor *Jean-Marie Messier, former CEO of Vivendi Universal *Marc Messier, Canadian actor from Quebec *Mark Messier, former NHL player, Hall of fame class 2007 *Paul Arthur Messier, art conservator Other uses *Messier object, a set of 110 astronomical objects *Messier (crater) *Messier (automobile) Messier was a French automobile manufacturer, based at Montrouge, on the southern edge of Paris, from 1925 till 1931.Linz, Schrader: ''Die Internationale Automobil-Enzyklopädie.''Georgano: ''The Beaulieu Encyclopedia of the Automobile.''Georgan ..., a French car produced 1925–1931 * Messier-Dowty and preceding companies in manufacture of aircraft undercarriage {{disambiguation, surname French-language surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IC 1459
IC 1459 (also catalogued as ''IC 5265'') is an elliptical galaxy located in the constellation Grus. It is located at a distance of circa 85 million light-years from Earth, which, given its apparent dimensions, means that IC 1459 is about 130,000 light-years across. It was discovered by Edward Emerson Barnard in 1892. Characteristics IC 1459 is a giant elliptical galaxy. In its core has been observed a fast counter-rotating stellar component, with an estimated total mass of . The stars of this component have circular orbits on a flat disk with a radius of less than two arcseconds. It has been suggested that the stars of the counterrotating disk are of external origin, either by the accretion of a stellar satellite or of a dense molecular cloud from which the stars were created. The galaxy also features multiple shells and disturbed isophotes, which indicate that it has accreted material, probably by the merger of smaller galaxies with the elliptical galaxy. Enhanced photography ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HE0450-2958
HE0450-2958 is an unusual quasar. It has been called the "naked quasar" and the "quasar without a home" because it appears to lack a host galaxy. It is estimated to lie approximately one billion parsecs away. History A team of researchers led by Pierre Magain of the University of Liège, Belgium announced their findings in the September 14, 2005 issue of the journal ''Nature''.Magain, P. et al. (2005) Discovery of a bright quasar without a massive host galaxy ''Nature'', 437, 381 The quasar lies close in the sky to a disturbed, starburst galaxy (see figure, upper left). However, no galaxy was seen around the quasar itself (figure, middle), leading the authors to speculate One might suggest that the host galaxy has disappeared from our view as a result of the collision hich formed the disturbed galaxy but it is hard to imagine how the complete disruption of a galaxy could happen. In order for the quasar's host galaxy to have escaped detection, Magain et al. estimated that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
