title: White dwarf

text: White dwarfs have low luminosity and therefore occupy a strip at the bottom of the Hertzsprung–Russell diagram, a graph of stellar luminosity versus color or temperature. They should not be confused with low-luminosity objects at the low-mass end of the main sequence, such as the hydrogen-fusing red dwarfs, whose cores are supported in part by thermal pressure, or the even lower-temperature brown dwarfs.


title: White dwarf

text: The relationship between the mass and radius of white dwarfs can be derived using an energy minimization argument. The energy of the white dwarf can be approximated by taking it to be the sum of its gravitational potential energy and kinetic energy. The gravitational potential energy of a unit mass piece of white dwarf, , will be on the order of , where is the gravitational constant, "M" is the mass of the white dwarf, and is its radius.


title: White dwarf

text: The kinetic energy of the unit mass, , will primarily come from the motion of electrons, so it will be approximately , where is the average electron momentum, is the electron mass, and is the number of electrons per unit mass. Since the electrons are degenerate, we can estimate to be on the order of the uncertainty in momentum, , given by the uncertainty principle, which says that is on the order of the reduced Planck constant, "ħ". will be on the order of the average distance between electrons, which will be approximately , i.e., the reciprocal of the cube root of the number density, , of electrons per unit volume. Since there are electrons in the white dwarf, where is the star's mass and its volume is on the order of , will be on the order of .


title: White dwarf

text: The white dwarf will be at equilibrium when its total energy, , is minimized. At this point, the kinetic and gravitational potential energies should be comparable, so we may derive a rough mass-radius relationship by equating their magnitudes:


title: White dwarf

text: Dropping , which depends only on the composition of the white dwarf, and the universal constants leaves us with a relationship between mass and radius:


title: White dwarf

text: Since this analysis uses the non-relativistic formula for the kinetic energy, it is non-relativistic. If we wish to analyze the situation where the electron velocity in a white dwarf is close to the speed of light, , we should replace by the extreme relativistic approximation for the kinetic energy. With this substitution, we find


title: White dwarf

text: To interpret this result, observe that as we add mass to a white dwarf, its radius will decrease, so, by the uncertainty principle, the momentum, and hence the velocity, of its electrons will increase. As this velocity approaches , the extreme relativistic analysis becomes more exact, meaning that the mass  of the white dwarf must approach a limiting mass of . Therefore, no white dwarf can be heavier than the limiting mass , or 1.4 .


title: White dwarf

text: For a more accurate computation of the mass-radius relationship and limiting mass of a white dwarf, one must compute the equation of state which describes the relationship between density and pressure in the white dwarf material. If the density and pressure are both set equal to functions of the radius from the center of the star, the system of equations consisting of the hydrostatic equation together with the equation of state can then be solved to find the structure of the white dwarf at equilibrium. In the non-relativistic case, we will still find that the radius is inversely proportional to the cube root of the mass. Relativistic corrections will alter the result so that the radius becomes zero at a finite value of the mass. This is the limiting value of the mass – called the "Chandrasekhar limit" – at which the white dwarf can no longer be supported by electron degeneracy pressure. The graph on the right shows the result of such a computation. It shows how radius varies with mass for non-relativistic (blue curve) and relativistic (green curve) models of a white dwarf. Both models treat the white dwarf as a cold Fermi gas in hydrostatic equilibrium. The average molecular weight per electron, , has been set equal to 2. Radius is measured in standard solar radii and mass in standard solar masses.


title: White dwarf

text: These computations all assume that the white dwarf is non-rotating. If the white dwarf is rotating, the equation of hydrostatic equilibrium must be modified to take into account the centrifugal pseudo-force arising from working in a rotating frame. For a uniformly rotating white dwarf, the limiting mass increases only slightly. If the star is allowed to rotate nonuniformly, and viscosity is neglected, then, as was pointed out by Fred Hoyle in 1947, there is no limit to the mass for which it is possible for a model white dwarf to be in static equilibrium. Not all of these model stars will be dynamically stable.


title: White dwarf

text: Rotating White Dwarfs and the estimates of their diameter in terms of the angular velocity of rotation has been treated in the rigorous mathematical literature. The fine structure of the free boundary of white dwarfs has also been analysed mathematically rigorously.


title: White dwarf

text: The degenerate matter that makes up the bulk of a white dwarf has a very low opacity, because any absorption of a photon requires that an electron must transition to a higher empty state, which may not be possible as the energy of the photon may not be a match for the possible quantum states available to that electron, hence radiative heat transfer within a white dwarf is low; it does, however, have a high thermal conductivity. As a result, the interior of the white dwarf maintains a uniform temperature, approximately 10 K. An outer shell of non-degenerate matter cools from approximately 10 K to 10 K. This matter radiates roughly as a black body. A white dwarf remains visible for a long time, as its tenuous outer atmosphere of normal matter begins to radiate at about 10 K, upon formation, while its greater interior mass is at 10 K but cannot radiate through its normal matter shell.


title: White dwarf

text: The visible radiation emitted by white dwarfs varies over a wide color range, from the whitish-blue color of an O, B or A-type main sequence star to the yellow-orange of a late K or early M-type star. White dwarf effective surface temperatures extend from over 150,000 K to barely under 4,000 K. In accordance with the Stefan–Boltzmann law, luminosity increases with increasing surface temperature (proportional to T⁴); this surface temperature range corresponds to a luminosity from over 100 times the Sun's to under that of the Sun's. Hot white dwarfs, with surface temperatures in excess of 30,000 K, have been observed to be sources of soft (i.e., lower-energy) X-rays. This enables the composition and structure of their atmospheres to be studied by soft X-ray and extreme ultraviolet observations.


title: White dwarf

text: White dwarfs also radiate neutrinos through the Urca process. This process has more effect on hotter and younger white dwarfs.


title: White dwarf

text: As was explained by Leon Mestel in 1952, unless the white dwarf accretes matter from a companion star or other source, its radiation comes from its stored heat, which is not replenished. White dwarfs have an extremely small surface area to radiate this heat from, so they cool gradually, remaining hot for a long time. As a white dwarf cools, its surface temperature decreases, the radiation which it emits reddens, and its luminosity decreases. Since the white dwarf has no energy sink other than radiation, it follows that its cooling slows with time. The rate of cooling has been estimated for a carbon white dwarf of 0.59 with a hydrogen atmosphere. After initially taking approximately 1.5 billion years to cool to a surface temperature of 7,140 K, cooling approximately 500 more kelvins to 6,590 K takes around 0.3 billion years, but the next two steps of around 500 kelvins (to 6,030 K and 5,550 K) take first 0.4 and then 1.1 billion years.


title: White dwarf

text: Most observed white dwarfs have relatively high surface temperatures, between 8,000 K and 40,000 K. A white dwarf, though, spends more of its lifetime at cooler temperatures than at hotter temperatures, so we should expect that there are more cool white dwarfs than hot white dwarfs. Once we adjust for the selection effect that hotter, more luminous white dwarfs are easier to observe, we do find that decreasing the temperature range examined results in finding more white dwarfs. This trend stops when we reach extremely cool white dwarfs; few white dwarfs are observed with surface temperatures below 4,000 K, and one of the coolest so far observed, WD 0346+246, has a surface temperature of approximately 3,800 K. The reason for this is that the Universe's age is finite; there has not been enough time for white dwarfs to cool below this temperature. The white dwarf luminosity function can therefore be used to find the time when stars started to form in a region; an estimate for the age of our Galactic disk found in this way is 8 billion years. A white dwarf will eventually, in many trillions of years, cool and become a non-radiating "black dwarf" in approximate thermal equilibrium with its surroundings and with the cosmic background radiation. No black dwarfs are thought to exist yet.


title: White dwarf

text: Although white dwarf material is initially plasma – a fluid composed of nuclei and electrons – it was theoretically predicted in the 1960s that at a late stage of cooling, it should crystallize, starting at its center. The crystal structure is thought to be a body-centered cubic lattice. In 1995 it was suggested that asteroseismological observations of pulsating white dwarfs yielded a potential test of the crystallization theory, and in 2004, observations were made that suggested approximately 90% of the mass of BPM 37093 had crystallized. Other work gives a crystallized mass fraction of between 32% and 82%. As a white dwarf core undergoes crystallization into a solid phase, latent heat is released which provides a source of thermal energy that delays its cooling. This effect was first confirmed in 2019 after the identification of a pile up in the cooling sequence of more than 15,000 white dwarfs observed with the "Gaia" satellite.


title: White dwarf

text: Low-mass helium white dwarfs (mass ), often referred to as "extremely low-mass white dwarfs, ELM WDs" are formed in binary systems. As a result of their hydrogen-rich envelopes, residual hydrogen burning via the CNO cycle may keep these white dwarfs hot on a long timescale. In addition, they remain in a bloated proto-white dwarf stage for up to 2 Gyr before they reach the cooling track.


title: White dwarf

text: Although most white dwarfs are thought to be composed of carbon and oxygen, spectroscopy typically shows that their emitted light comes from an atmosphere which is observed to be either hydrogen or helium dominated. The dominant element is usually at least 1,000 times more abundant than all other elements. As explained by Schatzman in the 1940s, the high surface gravity is thought to cause this purity by gravitationally separating the atmosphere so that heavy elements are below and the lighter above. This atmosphere, the only part of the white dwarf visible to us, is thought to be the top of an envelope which is a residue of the star's envelope in the AGB phase and may also contain material accreted from the interstellar medium. The envelope is believed to consist of a helium-rich layer with mass no more than of the star's total mass, which, if the atmosphere is hydrogen-dominated, is overlain by a hydrogen-rich layer with mass approximately of the stars total mass.


title: White dwarf

text: Although thin, these outer layers determine the thermal evolution of the white dwarf. The degenerate electrons in the bulk of a white dwarf conduct heat well. Most of a white dwarf's mass is therefore at almost the same temperature (isothermal), and it is also hot: a white dwarf with surface temperature between 8,000 K and 16,000 K will have a core temperature between approximately 5,000,000 K and 20,000,000 K. The white dwarf is kept from cooling very quickly only by its outer layers' opacity to radiation.


title: White dwarf

text: The first attempt to classify white dwarf spectra appears to have been by G. P. Kuiper in 1941, and various classification schemes have been proposed and used since then. The system currently in use was introduced by Edward M. Sion, Jesse L. Greenstein and their coauthors in 1983 and has been subsequently revised several times. It classifies a spectrum by a symbol which consists of an initial D, a letter describing the primary feature of the spectrum followed by an optional sequence of letters describing secondary features of the spectrum (as shown in the adjacent table), and a temperature index number, computed by dividing 50,400 K by the effective temperature. For example:


title: White dwarf

text: White dwarfs whose primary spectral classification is DA have hydrogen-dominated atmospheres. They make up the majority, approximately 80%, of all observed white dwarfs. The next class in number is of DBs, approximately 16%. The hot, above 15,000 K, DQ class (roughly 0.1%) have carbon-dominated atmospheres. Those classified as DB, DC, DO, DZ, and cool DQ have helium-dominated atmospheres. Assuming that carbon and metals are not present, which spectral classification is seen depends on the effective temperature. Between approximately 100,000 K to 45,000 K, the spectrum will be classified DO, dominated by singly ionized helium. From 30,000 K to 12,000 K, the spectrum will be DB, showing neutral helium lines, and below about 12,000 K, the spectrum will be featureless and classified DC.


title: White dwarf

text: Around 25–33% of white dwarfs have metal lines in their spectra, which is notable because any heavy elements in a white dwarf should sink into the star's interior in just a small fraction of the star's lifetime. The prevailing explanation for metal-rich white dwarfs is that they have recently accreted rocky planetesimals. The bulk composition of the accreted object can be measured from the strengths of the metal lines. For example, a 2015 study of the white dwarf Ton 345 concluded that its metal abundances were consistent with those of a differentiated, rocky planet whose mantle had been eroded by the host star's wind during its asymptotic giant branch phase.


title: White dwarf

text: Magnetic fields in white dwarfs with a strength at the surface of c. 1 million gauss (100 teslas) were predicted by P. M. S. Blackett in 1947 as a consequence of a physical law he had proposed which stated that an uncharged, rotating body should generate a magnetic field proportional to its angular momentum. This putative law, sometimes called the "Blackett effect", was never generally accepted, and by the 1950s even Blackett felt it had been refuted. In the 1960s, it was proposed that white dwarfs might have magnetic fields due to conservation of total surface magnetic flux that existed in its progenitor star phase. A surface magnetic field of c. 100 gauss (0.01 T) in the progenitor star would thus become a surface magnetic field of c. 100·100 = 1 million gauss (100 T) once the star's radius had shrunk by a factor of 100. The first magnetic white dwarf to be discovered was GJ 742 (also known as ) which was identified by James Kemp, John Swedlund, John Landstreet and Roger Angel in 1970 to host a magnetic field by its emission of circularly polarized light. It is thought to have a surface field of approximately 300 million gauss (30 kT).


title: White dwarf

text: Since 1970 magnetic fields have been discovered in well over 200 white dwarfs, ranging from to  gauss (0.2 T to 100 kT). The large number of presently known magnetic white dwarfs is due to the fact that most white dwarfs are identified by low-resolution spectroscopy, which is able to reveal the presence of a magnetic field of 1 megagauss or more. Thus the basic identification process also sometimes results in discovery of magnetic fields. It has been estimated that at least 10% of white dwarfs have fields in excess of 1 million gauss (100 T).


title: White dwarf

text: The highly magnetized white dwarf in the binary system AR Scorpii was identified in 2016 as the first pulsar in which the compact object is a white dwarf instead of a neutron star.


title: White dwarf

text: The magnetic fields in a white dwarf may allow for the existence of a new type of chemical bond, perpendicular paramagnetic bonding, in addition to ionic and covalent bonds, resulting in what has been initially described as "magnetized matter" in research published in 2012.


title: White dwarf

text: Early calculations suggested that there might be white dwarfs whose luminosity varied with a period of around 10 seconds, but searches in the 1960s failed to observe this. The first variable white dwarf found was HL Tau 76; in 1965 and 1966, and was observed to vary with a period of approximately 12.5 minutes. The reason for this period being longer than predicted is that the variability of HL Tau 76, like that of the other pulsating variable white dwarfs known, arises from non-radial gravity wave pulsations. Known types of pulsating white dwarf include the "DAV", or "ZZ Ceti", stars, including HL Tau 76, with hydrogen-dominated atmospheres and the spectral type DA; "DBV", or "V777 Her", stars, with helium-dominated atmospheres and the spectral type DB; and "GW Vir stars", sometimes subdivided into "DOV" and "PNNV" stars, with atmospheres dominated by helium, carbon, and oxygen. GW Vir stars are not, strictly speaking, white dwarfs, but are stars which are in a position on the Hertzsprung-Russell diagram between the asymptotic giant branch and the white dwarf region. They may be called "pre-white dwarfs". These variables all exhibit small (1%–30%) variations in light output, arising from a superposition of vibrational modes with periods of hundreds to thousands of seconds. Observation of these variations gives asteroseismological evidence about the interiors of white dwarfs.


title: White dwarf

text: White dwarfs are thought to represent the end point of stellar evolution for main-sequence stars with masses from about 0.07 to 10 . The composition of the white dwarf produced will depend on the initial mass of the star. Current galactic models suggest the Milky Way galaxy currently contains about ten billion white dwarfs.


title: White dwarf

text: If the mass of a main-sequence star is lower than approximately half a solar mass, it will never become hot enough to fuse helium in its core. It is thought that, over a lifespan that considerably exceeds the age of the Universe (c. 13.8 billion years), such a star will eventually burn all its hydrogen, for a while becoming a blue dwarf, and end its evolution as a helium white dwarf composed chiefly of helium-4 nuclei. Due to the very long time this process takes, it is not thought to be the origin of the observed helium white dwarfs. Rather, they are thought to be the product of mass loss in binary systems or mass loss due to a large planetary companion.


title: White dwarf

text: If the mass of a main-sequence star is between 0.5 and 8  like our sun, its core will become sufficiently hot to fuse helium into carbon and oxygen via the triple-alpha process, but it will never become sufficiently hot to fuse carbon into neon. Near the end of the period in which it undergoes fusion reactions, such a star will have a carbon–oxygen core which does not undergo fusion reactions, surrounded by an inner helium-burning shell and an outer hydrogen-burning shell. On the Hertzsprung–Russell diagram, it will be found on the asymptotic giant branch. It will then expel most of its outer material, creating a planetary nebula, until only the carbon–oxygen core is left. This process is responsible for the carbon–oxygen white dwarfs which form the vast majority of observed white dwarfs.


title: White dwarf

text: If a star is massive enough, its core will eventually become sufficiently hot to fuse carbon to neon, and then to fuse neon to iron. Such a star will not become a white dwarf, because the mass of its central, non-fusing core, initially supported by electron degeneracy pressure, will eventually exceed the largest possible mass supportable by degeneracy pressure. At this point the core of the star will collapse and it will explode in a core-collapse supernova which will leave behind a remnant neutron star, black hole, or possibly a more exotic form of compact star. Some main-sequence stars, of perhaps 8 to 10 , although sufficiently massive to fuse carbon to neon and magnesium, may be insufficiently massive to fuse neon. Such a star may leave a remnant white dwarf composed chiefly of oxygen, neon, and magnesium, provided that its core does not collapse, and provided that fusion does not proceed so violently as to blow apart the star in a supernova. Although a few white dwarfs have been identified which may be of this type, most evidence for the existence of such comes from the novae called "ONeMg" or "neon" novae. The spectra of these novae exhibit abundances of neon, magnesium, and other intermediate-mass elements which appear to be only explicable by the accretion of material onto an oxygen-neon-magnesium white dwarf.


title: White dwarf

text: Type Iax supernova, that involve helium accretion by a white dwarf, have been proposed to be a channel for transformation of this type of stellar remnant. In this scenario, the carbon detonation produced in a Type Ia supernova is too weak to destroy the white dwarf, expelling just a small part of its mass as ejecta, but produces an asymmetric explosion that kicks the star, often known as a "zombie star", to high speeds of a hypervelocity star. The matter processed in the failed detonation is re-accreted by the white dwarf with the heaviest elements such as iron falling to its core where it accumulates. These "iron-core" white dwarfs would be smaller than the carbon–oxygen kind of similar mass and would cool and crystallize faster than those.


title: White dwarf

text: A white dwarf is stable once formed and will continue to cool almost indefinitely, eventually to become a black dwarf. Assuming that the Universe continues to expand, it is thought that in 10 to 10 years, the galaxies will evaporate as their stars escape into intergalactic space. White dwarfs should generally survive galactic dispersion, although an occasional collision between white dwarfs may produce a new fusing star or a super-Chandrasekhar mass white dwarf which will explode in a Type Ia supernova. The subsequent lifetime of white dwarfs is thought to be on the order of the hypothetical lifetime of the proton, known to be at least 10–10 years. Some grand unified theories predict a proton lifetime between 10 and 10 years. If these theories are not valid, the proton might still decay by complicated nuclear reactions or through quantum gravitational processes involving virtual black holes; in these cases, the lifetime is estimated to be no more than 10 years. If protons do decay, the mass of a white dwarf will decrease very slowly with time as its nuclei decay, until it loses enough mass to become a nondegenerate lump of matter, and finally disappears completely.


title: White dwarf

text: A white dwarf can also be cannibalized or evaporated by a companion star, causing the white dwarf to lose so much mass that it becomes a planetary mass object. The resultant object, orbiting the former companion, now host star, could be a helium planet or diamond planet.


title: White dwarf

text: A white dwarf's stellar and planetary system is inherited from its progenitor star and may interact with the white dwarf in various ways. There are several indications that a white dwarf has a remnant planetary system.


title: White dwarf

text: The most common observable evidence of a remnant planetary system is pollution of the spectrum of a white dwarf with metal absorption lines. 27-50% of white dwarfs show a spectrum polluted with metals, but these heavy elements settle out in the atmosphere of white dwarfs colder than 20,000 K. The most widely accepted hypothesis is that this pollution comes from tidally disrupted rocky bodies. The first observation of a metal-polluted white dwarf was by van Maanen in 1917 at the Mount Wilson Observatory and is now recognized as the first evidence of exoplanets in astronomy. The white dwarf van Maanen 2 shows iron, calcium and magnesium in its atmosphere, but van Maanen misclassified it as the faintest F-type star based on the Calcium H- and K-lines. The following heavy elements were discovered in the atmosphere of white dwarfs: Ca, Mg, Fe, Na, Si, Cr, C, O, Al?, Sc, Ti, V, Mn, Co, Ni, Cu, Sr, S, P, N, Li, K, Be. The nitrogen in white dwarfs is thought to come from nitrogen-ice of extrasolar Kuiper Belt Objects, the lithium is thought to come from accreted crust material and the beryllium is thought to come from Exomoons.


title: White dwarf

text: A less common observable evidence is infrared excess due to a flat and optically thick debris disk, which is found around 1-4% of white dwarfs. The first white dwarf with infrared excess was discovered by Zuckerman&Becklin in 1987 in the near-infrared around Giclas 29-38 and later confirmed as a debris disk. White dwarfs hotter than 27,000 K sublimate all the dust formed by tidally disrupting a rocky body, preventing the formation of a debris disk. In colder white dwarfs a rocky body might be tidally disrupted near the Roche-Radius and forced into a circular orbit by the Poynting-Robertson drag, which is stronger for less massive white dwarfs. The Poynting-Robertson drag will also cause the dust to orbit closer and closer towards the white dwarf, until it will eventually sublimate and the disk will disappear. A debris disk will have a lifetime of around a few million years for white dwarfs hotter than 10,000 K. Colder white dwarfs can have disk-lifetimes of a few 10 million years, which is enough time to tidally disrupt a second rocky body and forming a second disk around a white dwarf, such as the two rings around LSPM J0207+3331.


title: White dwarf

text: The least common observable evidence of planetary systems are detected major or minor planets. Only a handful giant planets and a handful of minor planets are known around white dwarfs. It is a growing list with discoveries of around 6 exoplanets expected with Gaia and 4 exoplanets with JWST.Infrared spectroscopic observations made by NASA's Spitzer Space Telescope of the central star of the Helix Nebula suggest the presence of a dust cloud, which may be caused by cometary collisions. It is possible that infalling material from this may cause X-ray emission from the central star. Similarly, observations made in 2004 indicated the presence of a dust cloud around the young (estimated to have formed from its AGB progenitor about 500 million years ago) white dwarf G29-38, which may have been created by tidal disruption of a comet passing close to the white dwarf. Some estimations based on the metal content of the atmospheres of the white dwarfs consider that at least 15% of them may be orbited by planets and/or asteroids, or at least their debris. Another suggested idea is that white dwarfs could be orbited by the stripped cores of rocky planets, that would have survived the red giant phase of their star but losing their outer layers and, given those planetary remnants would likely be made of metals, to attempt to detect them looking for the signatures of their interaction with the white dwarf's magnetic field. Other suggested ideas of how white dwarfs are polluted with dust involve the scattering of asteroids by planets or via planet-planet scattering. Liberation of exomoons from their host planet could cause white dwarf pollution with dust. Either the liberation could cause asteroids to be scattered towards the white dwarf or the exomoon could be scattered into the Roche-Radius of the white dwarf. The mechanism behind the pollution of white dwarfs in binaries was also explored as these systems are more likely to lack a major planet, but this idea cannot explain the presence of dust around single white dwarfs. While old white dwarfs show evidence of dust accretion, white dwarfs older than ~1 billion years or >7000 K with dusty infrared excess were not detected until the discovery of LSPM J0207+3331 in 2018, which has a cooling age of ~3 billion years. The white dwarf shows two dusty components that are being explained with two rings with different temperatures.


title: White dwarf

text: The metal-rich white dwarf WD 1145+017 is the first white dwarf observed with a disintegrating minor planet which transits the star. The disintegration of the planetesimal generates a debris cloud which passes in front of the star every 4.5 hours, causing a 5-minute-long fade in the star's optical brightness. The depth of the transit is highly variable.


title: White dwarf

text: The giant planet WD J0914+1914b is being evaporated by the strong ultraviolet radiation of the hot white dwarf. Part of the evaporated material is being accreted in a gaseous disk around the white dwarf. The weak hydrogen line as well as other lines in the spectrum of the white dwarf revealed the presence of the giant planet.


title: White dwarf

text: The white dwarf WD 0145+234 shows brightening in the mid-infrared, seen in NEOWISE data. The brightening is not seen before 2018. It is interpreted as the tidal disruption of an exoasteroid, the first time such an event has been observed.


title: White dwarf

text: It has been proposed that white dwarfs with surface temperatures of less than 10,000 Kelvins could harbor a habitable zone at a distance of c. 0.005 to 0.02 AU that would last upwards of 3 billion years. This is so close that any habitable planets would be tidally locked. The goal is to search for transits of hypothetical Earth-like planets that could have migrated inward and/or formed there. As a white dwarf has a size similar to that of a planet, these kinds of transits would produce strong eclipses. Newer research casts some doubts on this idea, given that the close orbits of those hypothetical planets around their parent stars would subject them to strong tidal forces that could render them uninhabitable by triggering a greenhouse effect. Another suggested constraint to this idea is the origin of those planets. Leaving aside formation from the accretion disk surrounding the white dwarf, there are two ways a planet could end in a close orbit around stars of this kind: by surviving being engulfed by the star during its red giant phase, and then spiralling inward, or inward migration after the white dwarf has formed. The former case is implausible for low-mass bodies, as they are unlikely to survive being absorbed by their stars. In the latter case, the planets would have to expel so much orbital energy as heat, through tidal interactions with the white dwarf, that they would likely end as uninhabitable embers.


title: White dwarf

text: If a white dwarf is in a binary star system and is accreting matter from its companion, a variety of phenomena may occur, including novae and Type Ia supernovae. It may also be a super-soft x-ray source if it is able to take material from its companion fast enough to sustain fusion on its surface. On the other hand, phenomena in binary systems such as tidal interaction and star-disc interaction, moderated by magnetic fields or not, act on the rotation of accreting white dwarfs. In fact, the fastest-spinning, securely known white dwarfs, are members of binary systems (being the white dwarf in CTCV J2056-3014 the fastest one).


title: White dwarf

text: The mass of an isolated, nonrotating white dwarf cannot exceed the Chandrasekhar limit of ~1.4 . This limit may increase if the white dwarf is rotating rapidly and nonuniformly. White dwarfs in binary systems can accrete material from a companion star, increasing both their mass and their density. As their mass approaches the Chandrasekhar limit, this could theoretically lead to either the explosive ignition of fusion in the white dwarf or its collapse into a neutron star.


title: White dwarf

text: Accretion provides the currently favored mechanism called the "single-degenerate model" for Type Ia supernovae. In this model, a carbon–oxygen white dwarf accretes mass and compresses its core by pulling mass from a companion star. It is believed that compressional heating of the core leads to ignition of carbon fusion as the mass approaches the Chandrasekhar limit. Because the white dwarf is supported against gravity by quantum degeneracy pressure instead of by thermal pressure, adding heat to the star's interior increases its temperature but not its pressure, so the white dwarf does not expand and cool in response. Rather, the increased temperature accelerates the rate of the fusion reaction, in a runaway process that feeds on itself. The thermonuclear flame consumes much of the white dwarf in a few seconds, causing a Type Ia supernova explosion that obliterates the star. In another possible mechanism for Type Ia supernovae, the "double-degenerate model", two carbon–oxygen white dwarfs in a binary system merge, creating an object with mass greater than the Chandrasekhar limit in which carbon fusion is then ignited.


title: White dwarf

text: Observations have failed to note signs of accretion leading up to Type Ia supernovae, and this is now thought to be because the star is first loaded up to above the Chandrasekhar limit while also being spun up to a very high rate by the same process. Once the accretion stops the star gradually slows until the spin is no longer enough to prevent the explosion.


title: White dwarf

text: The historical bright SN 1006 is thought to have been a type Ia supernova from a white dwarf, possibly the merger of two white dwarfs. Tycho's Supernova of 1572 was also a type Ia supernova, and its remnant has been detected. A close candidate to being a survivor of a type Ia supernova is WD 0810-353.


title: White dwarf

text: A post-common envelope binary (PCEB) is a binary consisting of a white dwarf and a closely tidally-locked red dwarf (in other cases this might be a brown dwarf instead of a red dwarf). These binaries form when the red dwarf is engulfed in the red giant phase. As the red dwarf orbits inside the common envelope, it is slowed down in the denser environment. This slowed orbital speed is compensated with a decrease of the orbital distance between the red dwarf and the core of the red giant. The red dwarf spirals inwards towards the core and might merge with the core. If this does not happen and instead the common envelope is ejected, then the binary ends up in a close orbit, consisting of a white dwarf and a red dwarf. This type of binary is called a post-common envelope binary. The evolution of the PCEB continues as the two dwarf stars orbit closer and closer due to magnetic braking and by releasing gravitational waves. The binary might evolve at some point into a cataclysmic variable, and therefore post-common envelope binaries are sometimes called pre-cataclysmic variables.


title: White dwarf

text: Before accretion of material pushes a white dwarf close to the Chandrasekhar limit, accreted hydrogen-rich material on the surface may ignite in a less destructive type of thermonuclear explosion powered by hydrogen fusion. These surface explosions can be repeated as long as the white dwarf's core remains intact. This weaker kind of repetitive cataclysmic phenomenon is called a (classical) nova. Astronomers have also observed dwarf novae, which have smaller, more frequent luminosity peaks than the classical novae. These are thought to be caused by the release of gravitational potential energy when part of the accretion disc collapses onto the star, rather than through a release of energy due to fusion. In general, binary systems with a white dwarf accreting matter from a stellar companion are called cataclysmic variables. As well as novae and dwarf novae, several other classes of these variables are known, including polars and intermediate polars, both of which feature highly magnetic white dwarfs. Both fusion- and accretion-powered cataclysmic variables have been observed to be X-ray sources.


title: White dwarf

text: Other non-pro-supernova binaries include binaries that consist of a main sequence star (or giant) and a white dwarf. The binary Sirius AB is probably the most famous example. White dwarfs can also exist as binaries or multiple star systems that only consist of white dwarfs. An example of a resolved triple white dwarf system is WD J1953-1019, discovered with Gaia DR2 data. One interesting field is the study of remnant planetary systems around white dwarfs. While stars are bright and often outshine the exoplanets and brown dwarfs that orbit them, the white dwarfs are faint. This allows astronomers to study these brown dwarfs or exoplanets in more detail. The sub-brown dwarf around the white dwarf WD 0806−661 is one such example.


title: Santo Domingo

text: Santo Domingo ( meaning "Saint Dominic"), once known as Santo Domingo de Guzmán and Ciudad Trujillo, is the capital and largest city of the Dominican Republic and the largest metropolitan area in the Caribbean by population. As of 2022, the city and immediate surrounding area (the Distrito Nacional) had a population of 1,484,789, while the total population is 2,995,211 when including Greater Santo Domingo (the "metropolitan area"). The city is coterminous with the boundaries of the Distrito Nacional ("D.N.", "National District"), itself bordered on three sides by Santo Domingo Province.


title: Santo Domingo

text: Founded by the Spanish in 1496, on the east bank of the Ozama River and then moved by Nicolás de Ovando in 1502 to the west bank of the river, the city is the oldest continuously inhabited European settlement in the Americas, and was the first seat of the Spanish colonial rule in the New World, the Captaincy General of Santo Domingo. It is the site of the first university, cathedral, castle, monastery, and fortress in the New World. The city's Colonial Zone was declared as a World Heritage Site by UNESCO. Santo Domingo was called Ciudad Trujillo (), from 1936 to 1961, after the Dominican Republic's dictator, Rafael Trujillo, named the capital after himself. Following his assassination, the city resumed its original designation.


title: Santo Domingo

text: Santo Domingo is the cultural, financial, political, commercial and industrial center of the Dominican Republic, with the vast majority of the country's most important industries being located within the city. Santo Domingo also serves as the chief seaport of the country. The city's harbor at the mouth of the Ozama River accommodates the largest vessels, and the port handles both heavy passenger and freight traffic. Temperatures are high year round, with cooler breezes during winter time.


title: Santo Domingo

text: Prior to the arrival of Christopher Columbus in 1492, the native Taíno people populated the island which they called "Quisqueya", Kiskella (mother of all lands) and "Ayiti" (the land of the high mountains), and which Columbus later named Hispaniola, including the territory of today's Republic of Haiti. At the time, the island's territory consisted of five chiefdoms: Marién, Maguá, Maguana, Jaragua, and Higüey. These were ruled respectively by "caciques" (chiefs) Guacanagarix, Guarionex, Caonabo, Bohechío, and Cayacoa.


title: Santo Domingo

text: Dating from 1493, when the Spanish settled on the island, and officially from 5 August 1498, Santo Domingo became the oldest European city in the Americas. Bartholomew Columbus founded the settlement and named it La Nueva Isabela, after an earlier settlement in the north named after the Queen of Spain Isabella I. In 1495 it was renamed "Santo Domingo", in honor of Saint Dominic. Santo Domingo came to be known as the "Gateway to the Caribbean" and the chief town in Hispaniola from then on. Expeditions which led to Ponce de León's colonization of Puerto Rico, Diego Velázquez de Cuéllar's colonization of Cuba, Hernando Cortes' conquest of Mexico, and Vasco Núñez de Balboa's sighting of the Pacific Ocean were all launched from Santo Domingo.


title: Santo Domingo

text: In June 1502, Santo Domingo was destroyed by a major hurricane, and the new Governor Nicolás de Ovando had it rebuilt on a different site on the other side of the Ozama River. The original layout of the city and a large portion of its defensive wall can still be appreciated today throughout the Colonial Zone, declared a World Heritage Site by UNESCO.


title: Santo Domingo

text: Diego Columbus, Christopher Columbus' son, arrived in 1509, assuming the powers of Viceroy and admiral. In 1512, Ferdinand established a Real Audiencia with Juan Ortiz de Matienzo, Marcelo de Villalobos, and Lucas Vazquez de Ayllon appointed as judges of appeal. In 1514, Pedro Ibanez de Ibarra arrived with the Laws of Burgos. Rodrigo de Alburquerque was named "repartidor de indios" and soon named "visitadores" to enforce the laws.


title: Santo Domingo

text: The first major slave revolt in the Americas occurred in Santo Domingo during 1522, when enslaved Africans led an uprising on Diego Colombus's sugar plantation. In 1586, the privateer Sir Francis Drake captured the city and held it for ransom. A report which reached the English government in May 1586 states that from Santo Domingo he took away 1,200 Englishmen, Frenchmen, Flemings, and "Provincials out of prison, besides 800 of the countrey people". Drake's successful capture signaled the decline of Spain's dominion over Hispaniola, which was accentuated in the early 17th century by Spanish policies that resulted in the depopulation of most of the island outside of the capital. An expedition sent by Oliver Cromwell in 1655 attacked the city of Santo Domingo, but the English force was repulsed by a smaller force of local militias and Santo Domingo suffered only 25 dead. In 1697, the Treaty of Ryswick included the acknowledgement by Spain of France's dominion over the Western third of the island, now Haiti. During the 18th century, privateers from Santo Domingo patrolled the Caribbean, capturing numerous enemy merchantment.


title: Santo Domingo

text: From 1795 to 1822, the city changed hands several times along with the colony it headed. It was ceded to France in 1795. The city was briefly captured by Haitian rebels in 1801, recovered by France in 1802, endured a failed invasion from Haiti in 1805, and was once again reclaimed by Spain in 1809. In 1821, Santo Domingo became the capital of an independent nation called the Republic of Spanish Haiti after the Criollo bourgeois within the country, led by José Núñez de Cáceres, overthrew the Spanish crown. The nation was annexed by Haiti just two months later. The city and the colony lost much of their Spanish-born peninsular population as a result of these events which caused a great deal of instability and unrest.


title: Santo Domingo

text: On 27 February 1844 Santo Domingo was again the capital of a free nation, when it gained its independence from Haiti, led by Dominican nationalist Juan Pablo Duarte. The city was a prize fought over by various political factions over the succeeding decades of instability. In addition, the country had to fight multiple battles with Haiti; the Battle of 19 March, Battle of 30 March, Battle of Las Carreras, and Battle of Beler, are a few of the most prominent encounters, mentioned in the national anthem and with city streets named after them.


title: Santo Domingo

text: In 1861, Spain returned to the country, having struck a bargain with Dominican dictator Pedro Santana whereby the latter was granted several honorific titles and privileges, in exchange for annexing the young nation back to Spanish rule. The Dominican Restoration War began in 1863 however, and in 1865 the Bourbon Queen Isabella II withdrew her soldiers from the island.


title: Santo Domingo

text: Over the next two-thirds of a century Santo Domingo and the Dominican Republic went through many revolutions and power changes. Santo Domingo would experience the first of two U.S. invasions in 1916 when different leaders fought for presidential power and control of the city. The United States intervened, instituting a military leader, Harry Shepard Knapp. U.S. Marines and Dominicans clashed in Santo Domingo on October 24–25, 1916, resulting in the deaths of two U.S. Marines and three Dominicans.


title: Santo Domingo

text: The city was struck by hurricane San Zenón in 1930, which caused major damage and killed up to 8,000 people. After its rebuilding, Santo Domingo was known officially as Ciudad Trujillo due to the personality cult imposed by dictator Rafael Leónidas Trujillo, who governed from 1930. Following his assassination in 1961 the city was renamed back to Santo Domingo.


title: Santo Domingo

text: In 1962, Juan Bosch was elected to the presidency. He was overthrown seven months later, resulting in a civil war in the capital. Francisco Caamaño led the "Constitucionalistas" fighting to restore democracy. This would lead to the second U.S. invasion in 1965. U.S. troops engaged in heavy fighting in the streets of Santo Domingo against the "Constitucionalistas" on June 15 and June 16. Newsweek described it this way:


title: Santo Domingo

text: Eventually, the fighting would end on August 31, 1965, with 2,850 Dominicans and 44 American servicemen dead.


title: Santo Domingo

text: The year 1992 marked the 500th anniversary, El Quinto Centenario, of Christopher Columbus' Discovery of the Americas. The Columbus Lighthouse – Faro a Colón – was erected in Santo Domingo in honor of this occasion, with an approximate cost of 400 million Dominican pesos.


title: Santo Domingo

text: The Ozama River flows before emptying into the Caribbean Sea. Santo Domingo's position on its banks was of great importance to the city's economic development and the growth of trade during colonial times. The Ozama River is where the country's busiest port is located.


title: Santo Domingo

text: The average temperature in Santo Domingo varies little, because the tropical trade winds help mitigate the heat and humidity throughout the year. Thanks to these trade winds, Santo Domingo has a borderline tropical rainforest (Köppen "Af")/tropical monsoon climate ("Am"), as its driest month is very close to . However, the city seldom experiences the heat that one may expect to find. December through March are the coolest months with warm days with less humidity and cool nights (temperatures of ). July through September are the hottest. Santo Domingo averages of rain annually. Its driest months are from December through April, however, due to the trade winds and mountains to the southwest, rain is seen even during these months.


title: Santo Domingo

text: Like many other cities in the Caribbean, Santo Domingo is very susceptible to hurricanes. Hurricane Georges caused severe destruction in September 1998. The lowest recorded temperature has been on 5 February 1951 and 7 January 1957 and the highest is on 29 May 2002.


title: Santo Domingo

text: Many of Santo Domingo's most notable landmarks are located within the Zona Colonial district of the city, a UNESCO World Heritage Site since 1990. The Colonial Zone, bordered by the Río Ozama, also has an impressive collection of early 16th century buildings, including palatial houses and majestic churches that reflect the architectural style of the late Middle Ages. The Church and Convent of los Dominicos is the oldest Catholic building in continuous use in the Americas, and was the headquarters of the first university in the Americas.


title: Santo Domingo

text: The city's most important historical buildings include the Catedral Santa María La Menor, the first cathedral of the Americas, which states its distinction; the Alcázar de Colón, the first castle in the Americas, once the residence of Viceroy of the Indies Don Diego Colón, a son of Christopher Columbus; the Monasterio de San Francisco, the ruins of the first monastery in the Americas; the Museo de las Casas Reales, in a monumental complex that includes the former Palace of the Governors and the building of the former Royal Audiencia of Santo Domingo; the Fortaleza Ozama, is one of the surviving sections of the Walls of Santo Domingo, which is the oldest military construction of European origin in the Americas; the Pantéon Nacional, a former Jesuit edifice now hosting the remains of various renowned Dominicans; and the Dominican Convent, the first convent in the Americas.


title: Santo Domingo

text: On the north end of Calle Las Damas, the restored and expanded Plaza de España is bordered by Las Atarazanas (former naval yard, now a museum) and a number of small shops and restaurants. This area was the first European commercial center in the Americas, and is still a hub of activity today. The Alcázar de Colón, having once been the colonial palace of the Columbus family – beginning with his son Diego – is now a museum displaying period furniture and decorations. The building was originally built in 1510, and restored to its current appearance in 1952.


title: Santo Domingo

text: A 700 million US dollar investment was made in the Port of the Ozama river adjacent to the Ciudad Colonial aiming to turn Santo Domingo into a port of call for luxury cruise ships and including a privately owned marina. The project is being completed by Sans Soucí Ports S.A.


title: Santo Domingo

text: The city proper of Santo Domingo is subdivided into incorporated areas (neighborhoods) called "sectores" which could be considered as small urban towns. All "sectores" are serviced directly by the municipal mayor's office.


title: Santo Domingo

text: The demographics of Santo Domingo are similar to other metropolitan areas of the country, except that the population of immigrants (mainly Haitians) is larger in the city due to abundant jobs and economic dynamism compared to other provinces. Santo Domingo, like most of the country, is made up of native-born Dominican mulattos, though there are large numbers of Afro-Dominicans and Euro-Dominicans, as well as a large immigrant community. In fact, over 20% of the city's population is composed of immigrants, mainly Haitians. However, there are also recent immigrants from Europe, Asia, as well as other Latin American nations present in the city. The city of Santo Domingo has a significant community of Asians (mainly Chinese), Arabs (mostly Lebanese), and Europeans (mostly Spanish and Italian people) are also present in the city. The northeast quadrant of the city is the poorest while the southwest is wealthier. Santo Domingo is also considered one of the epicenters of the growing Dominican middle-class. The city is one of the most economically developed cities in Latin America. Santo Domingo's population in 2010 was 3.8 million in the metropolitan area.


title: Santo Domingo

text: Santo Domingo is the center of the national government of the Dominican Republic. The President's office and ministries, National Congress, Supreme Court of Justice, and other main government institutions are located in the metropolitan area.


title: Santo Domingo

text: The city is administered by the "Ayuntamiento del Distrito Nacional" (City Hall), which is responsible for municipal functions. The current mayor of Santo Domingo is Carolina Mejía de Garrigó.


title: Santo Domingo

text: The "Policía Nacional" (National Police) and "Policia Turística" (Tourist Police) (POLITUR) are tasked with enforcing city safety.


title: Santo Domingo

text: The city is the center of economic activity in the Dominican Republic. It is where most of the country's wealth is concentrated and the seat of the national legislature, judicial, and executive government. Many national and international firms have their headquarters or regional offices in Santo Domingo. The city attracts many international firms and franchises such as Ikea, Goldcorp and Barrick due to its location and economic stability.


title: Santo Domingo

text: The infrastructure is suitable for most business operations. A key element that has helped the city grow and compete globally is the telecommunications infrastructure. Santo Domingo and the Dominican Republic as a whole enjoy a modern and extensive telecommunications system liberalized in the late 1990s which has benefited from extensive foreign investment. This has attracted numerous call centers in recent years. Santo Domingo not only has an excellent telecommunications infrastructure but also a sizeable bilingual population that speaks English.


title: Santo Domingo

text: The city's economic growth can be witnessed in the extensive vertical growth experienced across many of its neighborhoods. The construction boom is reflected in the many high density residential towers, shopping malls, elevated highways, the metro expansion and overall increase in commercial activity.


title: Santo Domingo

text: Santo Domingo has a thriving middle class contrasting with the significant pockets of poverty that remain as challenges for the future. Marginalized slum conditions exist mostly in the northeast quadrant of the city with smaller pockets extending across the city. Areas of extensive development include the Poligono Central, which is bordered by the Avenida John F. Kennedy northward 27 February Avenue south, Avenida Winston Churchill to the west and Avenida Máximo Gómez to the east, and is characterized by its mixed development and its very active nightlife.


title: Santo Domingo

text: Santo Domingo has areas of high development, among them Serralles, Naco, Arroyo Hondo, Piantini, Urb Fernandez, Ens. Julieta, Paraiso, Los Prados, Bella Vista, Sarasota and other sectors, where most of the middle class can be found.


title: Santo Domingo

text: Bella Vista and La Esperilla are currently the fastest growing sectors with large mega -projects. Gazcue belongs to the more traditional southeastern area of the city and is known for its buildings dating from the 1930s to the 1960s.


title: Santo Domingo

text: The performing arts are very important in Santo Domingo. The city has its own symphonic orchestra, chamber orchestra, opera company, ballet company, folkloric company, and national theater, including a number of smaller groups. The Plaza of culture is the center of activity, but there are concerts, ballet, folklore, and other performances throughout the city. Casa de Teatro is the gathering place of avant garde artists, actors, and musicians. It stages art and literature exhibitions and offers painting, drama, and dancing courses and monthly contests for poetry, short stories, and other forms of literature.


title: Santo Domingo

text: Santo Domingo is the location of numerous museums, many of which are located in the Zona Colonial district. In the Zona Colonial is the Museum of Alcázar, in Diego Colon's palace, the Museum of the Casas Reales, with artefacts of the colonial period and a collection of ancient weapons donated by Trujillo, the Naval Museum of the Atarazanas, in the former naval yards, Museo de la Catedral, Museo Memorial de la Resistencia Dominicana, documenting the struggle for freedom during the regimes of Trujillo and Balaguer, Museo Duarte, dedicated to the hero of Dominican independence, and the World of Ambar Museum.


title: Santo Domingo

text: Plaza de la Cultura also houses the city's most important cultural venues, including the Teatro Nacional (National Theater) and various museums; the Palacio Nacional, which houses the Presidency of the Dominican Republic; the Palacio de Bellas Artes (Palace of Fine Arts), a neoclassical building that is the permanent home of the country's National Symphony Orchestra; and the Boulevard 27 de Febrero, a pedestrian promenade located on the busy Avenida 27 de Febrero, which displays works of art from prominent Dominican artists and sculptors. Another attraction is the Centro Olímpico Juan Pablo Duarte, a sports complex in the center of Santo Domingo. This complex was used during the 2003 Pan American Games.


title: Santo Domingo

text: In the Plaza de la Cultura are the Museum of the Dominican Man, with artifacts from the pre-Columbian Taíno civilization, the National Museum of History and Geography, the Museum of Natural History and the Museum of Modern Art. Other museums include the Museo Bellapart, a prominent private collection of 19th- and 20th-Century Dominican painting and sculpture and the Museo Prehispanico, a major private collection of pre-Columbian Taíno art.


title: Santo Domingo

text: Telecommunications in the Dominican Republic include radio, television, fixed and mobile telephones, and the Internet. There are 15 television stations (both UHF and VHF) in Santo Domingo. Santo Domingo has the greatest number of television signals in the country, followed by Santiago. Additional cable television channels are provided by companies like Aster, Cable TV Dominicana, SKY Dominicana, and Telecable. In Santo Domingo there are 100 different stations in AM frequency and 44 in FM frequency.


title: Santo Domingo

text: The city has various parks, many of which are relatively large. Santo Domingo (D.N) is surrounded by the Santo Domingo Greenbelt. Mirador Norte Park lies in the north of the city, close to Villa Mella and Mirador Sur Park is located in the southwest section of the city. Mirador del Este is located on the East bank of the Ozama river and it is the seat of the Columbus Lighthouse. Independencia Park and Colón Park are located in Zona Colonial. Zoo Parque Zoológico Nacional is home to a range of 82–100 both exotic and native plants and animal species.


title: Santo Domingo

text: There are eighteen universities in Santo Domingo, the highest number of any city in the Dominican Republic. Established in 1538, the Universidad Autónoma de Santo Domingo (UASD) is the oldest university in the Americas and is also the only public university in the city. Santo Domingo holds the nation's highest percentage of residents with a higher education degree.


title: Santo Domingo

text: Santo Domingo has an underground and elevated rapid transit metro system. It is the most extensive metro in the Caribbean and Central American region by total length and number of stations. The Santo Domingo Metro is part of a major "National Master Plan" to improve transportation in the city as well as the rest of the nation. The first line was planned to relieve traffic congestion in the Máximo Gómez and Hermanas Mirabal Avenue. The second line, which opened in April 2013, is meant to relieve the congestion along the Duarte-Kennedy-Centenario Corridor in the city from west to east. As of August 2013, the metro consists of these two lines. Four more lines are planned to be constructed in the near future, for a total of six. Before the opening of the second line, 30,856,515 passengers rode the Santo Domingo Metro in 2012. According to government figures more than 300,000 people ride the 31 kilometer system on a daily basis.


title: Santo Domingo

text: In 2018, a 5-kilometer Teleférico de Santo Domingo (aerial cable car) was opened to provide service to the poorest areas in the east and north of the metropolitan area, and serve as a feeder for the metro. The cable car is used by more than 12,000 people daily.


title: Santo Domingo

text: Santo Domingo is served by two airports. Aeropuerto Internacional La Isabela, a newly constructed airport located in the northern section of the city, within kilometers of the city center. It serves mostly domestic and charter flights. The major international airport that serves the city is Santo Domingo Las Americas, which serves North, Central and South America and also Europe.


title: Santo Domingo

text: The Port of Santo Domingo is located on the Ozama River. Its location at the center of the Caribbean is well suited for flexible itinerary planning and has excellent support, road and airport infrastructure within the Santo Domingo region, which facilitate access and transfers. The port is suitable for both turnaround and transit calls.


title: Santo Domingo

text: The port's renovation is part of a major redevelopment project, aimed at integrating the port area and the Zona Colonial and foster a cruise, yacht, and high-end tourism destination. Supported by legislation approved in 2005, the project, developed by the Sans Souci Group, also includes the development of a new sports marina and a mixed-leisure real estate development adjacent to the port.


title: Santo Domingo

text: Santo Domingo is the terminus for four of the five national highways. The city is connected to the southwest of the country by the national highway DR-2 (Avenida George Washington and Autopista 30 de Mayo), and with the cities of the country's northwest by DR-1 (Expreso Kennedy, Duarte), which serves as a direct link to the city of Santiago de los Caballeros. DR-3 (Expreso 27 de Febrero/Autopista de Las Américas) connects Santo Domingo directly to the east of the country, including the cities of San Pedro de Macorís, La Romana, and major tourist sites such as Punta Cana and Bávaro, and to the Samaná Province (in the northeast) via the Samana Highway. In the city, "motoconchos" (motorcycle taxis), "guaguas"/"voladoras" (low quality public buses), and "carros públicos"/"conchos" (shared taxis) are common modes of transport. The Santo Domingo Metro is the highest quality in the region of the Caribbean and Central America. It is composed of 2 lines that cross the city.


title: Santo Domingo

text: Expreso John F. Kennedy: This expressway crosses the National District from east to west in the north-central part. The Avenue consists of a total of ten lanes, five on each side. The two center lanes of the road are express lanes to facilitate transit. It also has several bypasses and elevated crossings.


title: Santo Domingo

text: Avenida 27 de Febrero: It is the main avenue to cross the National District from east to west in the central part of Santo Domingo. It starts at the Juan Bosch bridge and crosses the entire city until the roundabout at the Plaza de la Bandera, which extends into the town of Santo Domingo West and ends on the Duarte Highway. The thoroughfare is composed of a total of ten lanes. Five on each side. The four lanes in the center of the avenue are express that facilitate transit in the city from east to west, with several elevated cross streets, overpasses and tunnels. It also has exclusive bus lanes.


title: Santo Domingo

text: Avenida Simón Bolívar: It extends from Independence Park to the junction with the Avenue Winston Churchill. In its entirety, this avenue is composed of two local lanes one-way east- west.


title: Santo Domingo

text: Avenida Independencia: It extends from the intersection with Avenida Gregorio Luperón to Independence Park. The avenue consists of a total of four lanes (two eastbound and two westbound ) from crossing with Av G. Luperon to the intersection of Avenida Italia . From the junction with Av Italy until Independence Park Avenue becomes one-way eastbound and contains only two lanes.


title: Santo Domingo

text: Avenida George Washington: It is colloquially referred as "El Malecón" This is Santo Domingo's Maritime Boulevard, running alongside the Caribbean sea's waterfront. It extends from Palo Hincado Street to the intersection with Abraham Lincoln Avenue; from that point to the Haina River Highway 30 May extends also includes President Billini Walk, which starts in Palo Hincado street and joins the Avenida del Puerto along the western bank of the Ozama River. Throughout its entire length it is composed of four lanes (two on each side). On this Boulevard you will find the most exclusive hotels in the city, several casinos, the mixed business and residential high rise complex Malecón Center, the Obelisk and Eugenio María de Hostos' Park. This is also the Boulevard where the Santo Domingo Carnival parade takes place.


title: Santo Domingo

text: Avenida Winston Churchill: It extends from Kennedy Avenue to Avenida 27 de Febrero, from there on, it continues as Avenida Jimenez Moya to reach the Centro de los Heroes and finally the boardwalk. This thoroughfare is distinguished by its date palms that are planted on the sidewalks . Throughout its length the road is composed of six lanes (three on each side) and a large wooded median popularly known as Boulevard de la Churchill ("Churchill's Boulevard") and within this lies the Boulevard of the Stars.


title: Santo Domingo

text: Avenida Abraham Lincoln: extends from Avenida Kennedy to the seawall. The route consists of six lanes (three on each side) and a median suitable for jogging laid with palm trees. It traverses the city's commercial and leisure city center.


title: Santo Domingo

text: Avenida José Ortega y Gasset: It extends from the Paseo de los Reyes Católicos Avenue until 27 de Febrero. The avenue consists of four lanes, two on each side. Along this avenue lies the Centro Olímpico Juan Pablo Duarte athletic complex and the Hospital General de la Plaza de la Salud medical complex.


title: Santo Domingo

text: Avenida Tiradentes: It extends from the jetty in the south, through the state's university Universidad Autónoma de Santo Domingo. It extends to the north along Avenida 27 de Febrero, John F. Kennedy, and continuing north past the city's baseball stadium Estadio Quisqueya until it reaches the Parque Zoológico Nacional National Zoo.


title: Santo Domingo

text: Avenida Gregorio Luperón: It extends from Kennedy Avenue to Highway 30 May on the western edge of Santo Domingo. The thoroughfare consists of eight lanes, four on each side and a landscaped median. Local attractions located on this strip includes Gallístico Center Herrera Industrial Zone, and the Plaza de la Bandera.


title: Santo Domingo

text: Avenida Máximo Gómez y Báez: The city's main south–north avenue, it extends from the Malecón to the Presidente Peynado bridge. The boulevard consists of four lanes, two on each side. Major buildings and points of interest along this boulevard are: the National Cemetery, Plaza de la Cultura which houses the National Theatre and the Palace of Fine Arts. There are also two universities (UNAPEC and UTESA), as well as the headquarters of the People's Bank and five star hotel "Hotel Barceló Santo Domingo".


title: Santo Domingo

text: Avenida Juan Pablo Duarte: It extends from the intersection of Avenida Paseo and Martyrs of the Catholic Monarchs to Calle Padre Billini in the Colonial Zone . The avenue consists of three lanes on a road north–south direction becomes one lane to enter the Colonial Zone . This avenue is the main commerce route for low-income people throughout the metropolitan area with department stores, restaurants, and shops that offer goods and services at modest prices . In "Duarte" (as popularly known) you can find the New Market, the Enriquillo Park, Duarte Commercial Square and Santo Domingo's Chinatown.


title: Santo Domingo

text: Avenida Nicolás de Ovando y Cáceres: Is located on the northern part of Santo Domingo starting at the roundabout Cristo Rey sector and corner with Ortega y Gasset, Máximo Gómez, Arbert Duarte and Thomas avenues, among others; culminating in the sector of Simón Bolívar . This avenue is characterized by many businesses that sell auto parts .


title: Santo Domingo

text: Baseball is the most popular sport in the country, and was introduced by the United States Marines. Santo Domingo is home to two of the six teams in the Dominican Professional Baseball League.


title: Santo Domingo

text: These two teams are based in the Estadio Quisqueya located in Ensanche La Fe. In 2007 The stadium underwent a rebuilding job which expanded its number of seats and the overall look of the field. The bullpens are now enclosed and out of play. Former president Leonel Fernández also announced in 2009 that there are plans to turn the stadium and the adjacent area into a modern sports complex.


title: Santo Domingo

text: Santo Domingo's Basketball Tournament "Superior" is held in the National District each year, with several teams participating and representing several sectors and social clubs of the city.


title: Santo Domingo

text: The city hosted the 2005 FIBA Americas Championship, which was played at the Palacio de los Deportes Virgilio Travieso Soto.


title: Santo Domingo

text: Famous Dominican singer Juan Luis Guerra-Seijas was born on June 7th, 1957 in the capital city, Santo Domingo.


title: Arjuna

text: Arjuna (Sanskrit: अर्जुन, ), also known as Partha and Dhananjaya, is one of the chief protagonists of the Hindu epic "Mahabharata". In the epic, he is the third among five Pandava brothers, from the royal line of the Kuru Kingdom. In the Mahabharata War, Arjuna was a key warrior from the Pandava side and slew many warriors including Karna and Bhishma. Before the beginning of the war, his mentor, Krishna, gave him the supreme knowledge of Bhagavad Gita to overcome his moral dilemmas.


title: Arjuna

text: Arjuna was born when Indra, the god of heaven, blessed Kunti and Pandu with a son. From childhood, Arjuna was a brilliant student and was favoured by his beloved teacher, Drona. Arjuna is depicted as a skilled archer, winning the hands of Draupadi, who became the common wife of the Pandavas. Arjuna is twice exiled, first for breaking a pact with his brothers; and secondly together with them when his oldest brother was tricked into gambling away the throne.


title: Arjuna

text: Some notable incidents during the first exile were Arjuna's marriages with princesses Ulupi, Chitrāngadā and Subhadra. From his four wives, Arjuna had four sons, one from each wife Shrutakarma, Iravan, Babhruvahana and Abhimanyu. During his second exile, Arjuna gained many celestial weapons. Despite being a warrior, Arjuna was also skilled in music and dance. At the end of the epic, Pandavas, accompanied by Draupadi, retired to the Himalayas.


title: Arjuna

text: According to Monier Monier-Williams, the word "Arjuna" means white, clear or silver. He is known by many other names, such as:


title: Arjuna

text: The story of Arjuna is told in the "Mahabharata", one of the Sanskrit epics from the Indian subcontinent. The work is written in Classical Sanskrit and is a composite work of revisions, editing and interpolations over many centuries. The oldest parts in the surviving version of the text probably date to about 400 BCE.


title: Arjuna

text: The "Mahabharata" manuscripts exist in numerous versions, wherein the specifics and details of major characters and episodes vary, often significantly. Except for the sections containing the "Bhagavad Gita" which is remarkably consistent between the numerous manuscripts, the rest of the epic exists in many versions. The differences between the Northern and Southern recensions are particularly significant, with the Southern manuscripts more profuse and longer. Scholars have attempted to construct a critical edition, relying mostly on a study of the "Bombay" edition, the "Poona" edition, the "Calcutta" edition and the "south Indian" editions of the manuscripts. The most accepted version is one prepared by scholars led by Vishnu Sukthankar at the Bhandarkar Oriental Research Institute, preserved at Kyoto University, Cambridge University and various Indian universities.


title: Arjuna

text: Arjuna was one of the five Pandava brothers of royal lineage, whose collective name derives from their father and heir to the Lunar dynasty, Pandu. However, Pandu was under a curse whereby he would die if he had sexual relations with a woman and thus his sons were born using a mantra given to Kunti by sage Durvasa during her maiden days. His wivesMadri and Kuntiinvoked different gods and were blessed with children. According to the legend, Arjuna was a demigod, who was born as a blessing after his mother Kunti invoked the god Indra on her husband's request. Whilst the other epic such as "Devi Bhagavata" also records Arjuna as a reincarnation of a rishi called Nara.


title: Arjuna

text: Despite being the younger brother of Dhritarashtra, it was Pandu who succeeded their father as king of Bharata. This was because Dhritarashtra was blind, a disability that caused him to forfeit his right to the royal succession. Dhritarashtra fathered 100 sons, known as the Kaurava brothers, and ascended the throne on the death of Pandu. The Pandava brothers were then brought up with their cousins, the Kauravas, and the education of all these boys was supervised by Bhishma. Among their teachers was the brahmin warrior called Drona, who considered Arjuna to be his favourite. According to Swami Parmeshwaranand, Arjuna was Drona's most accomplished pupil. He notes an incident where Drona deemed that out of all his students, none but Arjuna had the steadfast focus to shoot the eye of a toy bird on a tree using a bow and arrow, and that Drona was proven right.


title: Arjuna

text: After the princes completed their training, Arjuna defeated Drupada of Panchala, who was impressed by the prince's skills, as the "gurudakshina" for his beloved teacher Drona. Later, Duryodhana and his maternal uncle Shakuni planned to burn Pandavas alive along with their mother Kunti. They built a palace out of lac in a village named Varanāvata. The Pandavas, though, managed to escape the house of lac with the help of Vidura through a secret tunnel.


title: Arjuna

text: Arjuna is a central character in the Hindu epics and appears in hundreds of situations. Among the most notable is his marriage to Draupadi, the fire born daughter of Drupada, who was the king of Panchala.


title: Arjuna

text: After the event of Lakshagriha, Arjuna, his mother and brothers decide to hide from Hastinapura. One day, Arjuna learns that Drupada is holding an archery tournament to determine who should marry his daughter. The tournament was to lift and string a bow, and fire arrows to pierce the eye of a golden fish only by looking at its reflection in the water. At the Swayamvara, almost all the assorted monarchs were unable to complete the challenge. In the end, Arjuna, dressed as a Brahmin, wins the tournament. Annoyed by their defeat, the kings attack Arjuna, but he defeats them and runs home to tell his mother of his success, shouting "look what we have found". Commentators vary as to whether Kunti thought he was referring to alms found in the forest or to some great prize unknown to her. She tells him that the find must be shared with his brothers, as they had always shared such things in the past.


title: Arjuna

text: This misunderstanding, combined with the protocol that the oldest of the brothers, Yudhishthira, should marry first, leads to the agreement that all five brothers marry her. This is one of the rare examples of polyandry in Sanskrit literature. The brothers agreed that none should intrude if Draupadi was alone with one of the others, the penalty for doing so is a year to be spent in exile during which the culprit must remain celibate.


title: Arjuna

text: When Arjuna, his siblings, mother and Draupadi returned to Hastinapura, Dhritarashtra determined to avoid a rivalry developing for control of Hastinapur by splitting the kingdom, with half of it being left to his own eldest son, Duryodhana, and half to the eldest son of Pandu, Yudhishthira.


title: Arjuna

text: Arjuna inadvertently broke the pact with his brothers, intruding as he sought to collect weapons whilst Yudhishthira, was alone with Draupadi. He felt obliged to go into exile despite Yudhishthira's attempts to dissuade him. It was this event that led to him forming a close relationship with his cousin Krishna because he ignored the celibacy condition of the pact and married three people on his travels, the first of whom was a Naga princess named Ulupi, with whom he had a son called Iravan. His second marriage was with a princess of Manipura, Chitrangada, who bore a son named Babhruvahana. The third was with Subhadra, the sister of Krishna. This last event, which took place in Dvaraka, is not the first meeting between Krishna and the Pandavas in the story but it does mark the start of a bond, sealed with the birth of the couple's child, Abhimanyu, whom Krishna adores.


title: Arjuna

text: It was while at Indraprastha, the capital city of the Pandavas, for the birth of Abhimanyu that Arjuna and Krishna become involved in what Alf Hiltebeitel describes as "one of the strangest scenes of the epic", this being the burning of the Khandava Forest. This story within a story has been interpreted in various ways.


title: Arjuna

text: The essence of this part of the myth is that Arjuna and Krishna are in the forest when they are approached by a hungry person. They agree to help satisfy his hunger, at which point he reveals himself to be Agni, the god of fire. Agni's hunger can only be sated by consuming the entire forest and everything in it but his previous attempts to do this were thwarted by Indra, who is a protector of the forest and sent down rains to quench the fire. The cousins agree to fend off Indra and anyone else who might interfere; to this end, Arjuna armed himself with the Gandiva bow and Krishna with his Sudarshana Chakra, weapons suitable for a fight with the gods. They then begin to destroy the forest, battling against Indra and other gods, as well as demons, animals and snakes. Once the forest has gone, after six days of fire and slaughter, Arjuna and Krishna receive thanks from Indra, who had retreated with the other gods partway through the proceedings on being commanded by a mysterious voice to step back and watch.


title: Arjuna

text: As heir to the lordship of Kurukshetra, Yudhishthira had attracted the unwelcome attention of his Kaurava cousin, Duryodhana, who sought the throne. The royal consecration involved an elaborate Vedic ceremony called rajasuya which extended over several years and included the playing of a ritualised game of dice. This particular game, described as "Indian literature's most notorious dice game" by Williams, was rigged by Duryodhana, causing Yudhishthira to gamble and lose everything, including his kingdom and his shared wife Draupadi. He and his brothers only obtained their freedom because Draupadi offered herself to the Kauravas in exchange. She was then humiliated by them so much that revenge for her treatment became a further motivation for the Pandavas in the rivalry with their cousins. During her humiliation, Karna called her a whore for marrying five men. This led Arjuna to take a vow of killing Karna. The brothers, including Arjuna, were forced into a 12-year exile, to be followed by a year living incognito if Yudhishthira was to regain his kingdom.


title: Arjuna

text: While in this exile, Arjuna performed twelve labours. He received instruction in the use of weapons from Parashurama, the sixth avatar of Vishnu, and visited the Himalayas to get celestial weapons that he would be able to use against the Kauravas. Thereafter, he honed his battle skills with a visit to Swarga, the heaven of Indra, where he emerged victorious in a battle with the Daityas and also fought for Indra, his spiritual father, with the Gandiva.


title: Arjuna

text: After the battle at Khandava, Indra had promised Arjuna to give him all his weapons as a boon for matching him in battle with the requirement that Shiva is pleased with him. During the exile, following the advice of Krishna to go on meditation or "tapasya" to attain this divine weapon, Arjuna left his brothers for a penance on Indrakeeladri Hill.


title: Arjuna

text: When Arjuna was in deep meditation, a wild boar ran towards him. He realized it and took out an arrow and shot it at the boar. But, another arrow had already pierced the boar. Arjuna was furious and he saw a hunter there. He confronted the hunter and they engaged in a fight. After hours of fighting, Arjuna was not able to defeat him and realized that the hunter was Shiva. Shiva was pleased and took his real form. He gave him Pashupatastra and told that the boar was Indra as he wanted to test Arjuna. After gaining the weapon, Indra took him to heaven and gave him many weapons.


title: Arjuna

text: During his exile, Arjuna was invited to the palace of Indra, his father. An apsara named Urvashi was impressed and attracted to Arjuna's look and talent so she expresses her love in front of him. But Arjuna did not have any intentions of making love to Urvashi. Instead, he called her “mother”. Because once Urvashi was the wife of King Pururavas the ancestor of Kuru dynasty. Urvashi felt insulted and cursed Arjuna that he will be a eunuch for the rest of his life. Later on Indra's request, Urvashi curtailed the curse to a period of one year.


title: Arjuna

text: Arjuna spent the last year of exile as a eunuch named Brihannala at King Virata’s Matsya Kingdom. He taught song and dance to the princess Uttarā. After Kichaka humiliated and tried to molest Draupadi, Arjuna consoled her and Bhima killed Kichaka. When Duryodhana and his army attacked Matsya, Uttar, Uttarā's brother, with Brihannala as his charioteer went to the army. Later that day, the year of Agyatavasa was over. Arjuna took Uttar away from the army to the forest where he had kept his divine bow, Gandiva and revealed his identity to Uttara. Later when he revealed his identity to everyone in the Matsya, Uttarā was married to Arjuna's son Abhimanyu.


title: Arjuna

text: The "Bhagavad Gita" is a book within the "Mahabharata" that depicts a dialogue between Arjuna and Krishna immediately prior to the commencement of the Kurukshetra War between the Pandavas and Kauravas. According to Richard H. Davis,


title: Arjuna

text: Arjuna was a key warrior in Pandava's victory in the Kurukshetra War. He killed many powerful and key warriors of Kaurava's side.


title: Arjuna

text: After the Kurukshetra War, Yudhishthira appointed Arjuna as the Prime Minister of Hastinapur. Yudhishthira performed Ashvamedha. Arjuna followed the horse to the land of Manipura and encountered Babhruvahana, one of his sons. None of them knew one another. Babhruvahana asked Arjuna to fight and killed his father during the battle. Chitrāngadā came to the battlefield and revealed that Arjuna was her husband and Babhruvahana's father. Ulupi, the second wife of Arjuna, revived Arjuna using a celestial gem called Nagamani.


title: Arjuna

text: After Krishna left his mortal body, Arjuna took the citizens of Dwaraka, including 16,100 wives of Krishna, to Indraprastha. On the way, they were attacked by a group of bandits. Arjuna desisted fighting seeing the law of time.


title: Arjuna

text: Upon the onset of the "Kali Yuga" and acting on the advice of Vyasa, Arjuna and other Pandavas retired, leaving the throne to Parikshit (Arjuna's grandson and Abhimanyu's son). Giving up all their belongings and ties, the Pandavas, accompanied by a dog, made their final journey of pilgrimage to the Himalayas. The listener of the Mahabharata is Janamejaya, Parikshit's son and Arjunaś great-grandson.


title: Arjuna

text: In the Indonesian archipelago, the figure of Arjuna is also known and has been famous for a long time. Arjuna especially became popular in the areas of Java, Bali, Madura and Lombok. In Java and later in Bali, Arjuna became the main character in several kakawin, such as Kakawin Arjunawiwāha, Kakawin Pārthayajña, and Kakawin Pārthāyana (also known as Kakawin Subhadrawiwāha. In addition, Arjuna is also found in several temple reliefs on the island of Java, for example the Surawana temple.


title: Arjuna

text: Arjuna is a well-known figure in the world of wayang (Indonesian Puppetry) in Javanese culture. Some of the characteristics of the wayang version of Arjuna may be different from that of Arjuna in the Indian version of the Mahābhārata book in Sanskrit. In the world of puppetry, Arjuna is described as a knight who likes to travel, meditate, and learn. Apart from being a student of Resi Drona at Padepokan Sukalima, he is also a student of Resi Padmanaba from the Untarayana Hermitage. Arjuna was a brahman in Goa Mintaraga, with the title Bagawan Ciptaning. He was made the superior knight of the gods to destroy Prabu Niwatakawaca, the giant king of the Manimantaka country. For his services, Arjuna was crowned king in Dewa Indra's heaven, with the title King Karitin and get the gift of magical heirlooms from the gods, including: Gendewa (from Bhatara Indra), Ardadadali Arrow (from Bhatara Kuwera), Cundamanik Arrow (from Bhatara Narada). After the Bharatayuddha war, Arjuna became king in Banakeling State, the former Jayadrata kingdom.


title: Arjuna

text: Arjuna has a smart and clever nature, is quiet, conscientious, polite, brave and likes to protect the weak. He leads the Madukara Duchy, within the territory of the state of Amarta. He is an unmatched fighter on the battlefield, even though he is slender, handsome as a virgin, soft-hearted despite the will of steel, a knight with a myriad of wives and lovers despite being able to do the toughest asceticism, a knight with deep family loyalty but then able to force himself to kill his half brother. For the older generation of Java, he was the embodiment of a whole man. Very different from Yudhisthira, he really enjoyed life in the world. His love adventures always amaze the Javanese, but he is strangely different from Don Juan who always chases women. It is said that Arjuna was so refined and handsome that such princesses, as well as the ladies-in-waiting, would immediately offer themselves. They are the ones who get the honor, not Arjuna. He is very different from Wrekudara. He displayed a graceful body and a gentleness that was appreciated by the Javanese of all generations.


title: Arjuna

text: Arjuna also has other powerful heirlooms, among others: The Kiai Kalanadah Keris was given to Gatotkaca when he married Dewi Gowa (Arjuna's son), Sangkali Arrow (from Resi Drona), Candranila Arrow, Sirsha Arrow, Sarotama Kiai Arrow, Pasupati Arrow (from Batara Guru), Panah Naracabala, Arrow Ardhadhedhali, Keris Kiai Baruna, Keris Pulanggeni (given to Abhimanyu), Terompet Dewanata, Cupu filled with Jayengkaton oil (given by Bagawan Wilawuk from Pringcendani hermitage) and Ciptawilaha Horse with Kiai Pamuk's whip. Meanwhile, Arjuna's spell includes: Panglimunan, Tunggengmaya, Sepiangin, Mayabumi, Pengasih and Asmaragama. Arjuna also has clothes that symbolize greatness, namely Kampuh or Limarsawo Cloth, Limarkatanggi Belt, Minangkara Gelung, Candrakanta Necklace and Mustika Ampal Ring (formerly belonging to King Ekalaya, the king of the Paranggelung state).


title: Mount Ararat

text: Mount Ararat is a snow-capped and dormant compound volcano in the extreme east of Turkey. It consists of two major volcanic cones: Greater Ararat and Little Ararat. Greater Ararat is the highest peak in Turkey and the Armenian Highland with an elevation of ; Little Ararat's elevation is . The Ararat massif is about wide at ground base. The first recorded efforts to reach Ararat's summit were made in the Middle Ages, and Friedrich Parrot, Khachatur Abovian, and four others made the first recorded ascent in 1829.


title: Mount Ararat

text: In Europe, the mountain has been called by the name Ararat since the Middle Ages, as it began to be identified with "mountains of Ararat" described in the Bible as the resting place of Noah's Ark, despite contention that does not refer specifically to a Mount Ararat.


title: Mount Ararat

text: Despite lying outside the borders of modern Armenia, the mountain is the principal national symbol of Armenia and has been considered a sacred mountain by Armenians. It is featured prominently in Armenian literature and art and is an icon for Armenian irredentism. It is depicted on the coat of arms of Armenia along with Noah's Ark.


title: Mount Ararat

text: Mount Ararat forms a near-quadripoint between Turkey, Armenia, Iran, and the Nakhchivan exclave of Azerbaijan. Its summit is located some west of both the Iranian border and the border of the Nakhchivan exclave of Azerbaijan, and south of the Armenian border. The Turkish–Armenian–Azerbaijani and Turkish–Iranian–Azerbaijani tripoints are some 8 km apart, separated by a narrow strip of Turkish territory containing the E99 road which enters Nakhchivan at .


title: Mount Ararat

text: From the 16th century until 1828 the range was part of the Ottoman-Persian border; Great Ararat's summit and the northern slopes, along with the eastern slopes of Little Ararat were controlled by Persia. Following the 1826–28 Russo-Persian War and the Treaty of Turkmenchay, the Persian controlled territory was ceded to the Russian Empire. Little Ararat became the point where the Turkish, Persian, and Russian imperial frontiers converged. The current international boundaries were formed throughout the 20th century. The mountain came under Turkish control during the 1920 Turkish–Armenian War. It formally became part of Turkey according to the 1921 Treaty of Moscow and Treaty of Kars. In the late 1920s, Turkey crossed the Iranian border and occupied the eastern flank of Lesser Ararat as part of its effort to quash the Kurdish Ararat rebellion, during which the Kurdish rebels used the area as a safe haven against the Turkish state. Iran eventually agreed to cede the area to Turkey in a territorial exchange. The Iran-Turkey boundary skirts east of Lesser Ararat, the lower peak of the Ararat massif.


title: Mount Ararat

text: Ararat ( "Ararad") is the Biblical Hebrew name (אררט "ʾrrṭ"; Tiberian vocalization אֲרָרָט "ʾărārāṭ"; Pesher Genesis הוררט "hōrārāṭ"), cognate with Assyrian Urartu, of a kingdom that existed in the Armenian Highlands in the 9th–6th centuries BC.


title: Mount Ararat

text: In the 19th century Wilhelm Gesenius speculated an origin from "Arjanwartah", an unattested Sanskrit word without any clear cognates, supposedly meaning "holy ground." Some Armenian historians, such as Ashot Melkonyan, link the origin of the word "Ararat" to the prefix of a number of placenames in the Armenian Highland ("ar–"), including the Armenians. The mountain is known as Ararat in European languages, however, none of the native peoples have traditionally referred to the mountain by that name. This mountain was not called by the name Ararat until the Middle Ages; early Armenian historians considered the biblical Ararat to be in Corduene.


title: Mount Ararat

text: The traditional Armenian name is Masis (Մասիս ; sometimes "Massis"). However, nowadays, the terms Masis and Ararat are both widely, often interchangeably, used in Armenian. The folk etymology expressed in Movses Khorenatsi's "History of Armenia" derives the name from king Amasya, the great-grandson of the legendary Armenian patriarch Hayk, who is said to have called the mountain "Masis" after himself.


title: Mount Ararat

text: Various etymologies have been proposed. Russian orientalist Anatoly Novoseltsev suggested that "Masis" derives from Middle Persian "masist", "the largest." According to Armenian historian the "mas" root in Masis means "mountain", cf. Proto-Indo-European *mņs-. According to archaeologist Armen Petrosyan, the name originates from the Māšu (Mashu) mountain mentioned in the "Epic of Gilgamesh", which sounded like "Māsu" in Assyrian. According to this theory, the name meant "twin," referring to the twin peaks of the mountain. "Erkuahi", a land mentioned in Urartian texts and identified with Mt. Ararat, could reflect the native Armenian-language form of this same name (compare to Armenian "erku" (երկու, meaning "two")).


title: Mount Ararat

text: The Turkish name is Ağrı Dağı (; "Ağır Dağ"), i.e. "Mountain of Ağrı". Ağrı literally translates to "pain" or "sorrow". This name has been known since the late Middle Ages. The 17th century explorer Evliya Çelebi referred to it as Ağrî in the "Seyahatnâme".


title: Mount Ararat

text: The Kurdish name of the mountain is Çiyayê Agirî , which translates to "fiery mountain". An alternative Kurdish name is Grîdax, which is composed of the word "grî", presumably a corrupted version of the Kurdish "girê", meaning hill, or "Agirî", and "dax", which is the Turkish "dağ", meaning mountain.


title: Mount Ararat

text: Despite the supposed meaning in Turkish "Ağrı Dağı" as "pain mountain" and Kurdish "Çiyayê Agirî" as "fiery mountain", some linguists underline a relationship between the mountain's name and a village on its slopes called "Ağori" that was decimated after a landslide in 1840. The exact meaning of these related names remains unknown.


title: Mount Ararat

text: In classical antiquity, particularly in Strabo's "Geographica", the peaks of Ararat were known in ancient Greek as Ἄβος ("Abos") and Νίβαρος ("Nibaros").


title: Mount Ararat

text: Mount Ararat is located in the Eastern Anatolia Region of Turkey between the provinces of Ağrı and Iğdır, near the border with Iran, Armenia and Nakhchivan exclave of Azerbaijan, between the Aras and Murat rivers. The Serdarbulak lava plateau, at 2600 meters of elevation, separates the peaks of Greater and Little Ararat. Mount Ararat's summit is located some west of the Turkey-Iran border and south of the Turco-Armenian border. The Ararat plain runs along its northwest to western side.


title: Mount Ararat

text: An elevation of for Mount Ararat is given by some encyclopedias and reference works such as "Merriam-Webster's Geographical Dictionary" and "Encyclopedia of World Geography". However, a number of sources, such as the United States Geological Survey and numerous topographic maps indicate that the alternatively widespread figure of is probably more accurate. The current elevation may be as low as due to the melting of its snow-covered ice cap.


title: Mount Ararat

text: The ice cap on the summit of Mount Ararat has been shrinking since at least 1957. In the late 1950s, Blumenthal observed that there existed 11 outlet glaciers emerging from a summit snow mass that covered about . At that time, it was found that the present glaciers on the summit of Ararat extend as low as an elevation of on the north-facing slope, and an elevation of


title: Mount Ararat

text: Blumenthal estimated that the snow line had been as low as in elevation during the Late Pleistocene. Such a snow line would have created an ice cap of in extent. However, he observed a lack of any clear evidence of prehistoric moraines other than those which were close to the 1958 glacier tongues. Blumenthal explained the absence of such moraines by the lack of confining ridges to control glaciers, insufficient debris load in the ice to form moraines, and their burial by later eruptions. Years later, Birman observed on the south-facing slopes a possible moraine that extends at least in altitude below the base of the 1958 ice cap at an elevation of . He also found two morainal deposits that were created by a Mount Ararat valley glacier of Pleistocene, possibly Wisconsinan (Last Glacial Maximum) age, downvalley from Lake Balık. The higher moraine lies at an altitude of about and the lower moraine lies at an altitude of about . The lower moraine occurs about downstream from Lake Balık. Both moraines are about high. It is suspected that Lake Balık occupies a glacial basin.


title: Mount Ararat

text: Mount Ararat is a polygenic, compound stratovolcano. Covering an area of , it is the largest volcanic edifice within the region. Along its northwest–southeast trending long axis, Mount Ararat is about long and is about long along its short axis. It consists of about of dacitic and rhyolitic pyroclastic debris and dacitic, rhyolitic, and basaltic lavas.


title: Mount Ararat

text: Mount Ararat consists of two distinct volcanic cones, Greater Ararat and Lesser Ararat (Little Ararat). The western volcanic cone, Greater Ararat, is a steep-sided volcanic cone that is larger and higher than the eastern volcanic cone. Greater Ararat is about wide at the base and rises about above the adjacent floors of the Iğdir and Doğubeyazıt basins. The eastern volcanic cone, Lesser Ararat, is high and across. These volcanic cones, which lie apart, are separated by a wide north–south-trending crack. This crack is the surface expression of an extensional fault. Numerous parasitic cones and lava domes have been built by flank eruptions along this fault and on the flanks of both of the main volcanic cones.


title: Mount Ararat

text: Mount Ararat lies within a complex, sinistral pull-apart basin that originally was a single, continuous depression. The growth of Mount Ararat partitioned this depression into two smaller basins, the Iğdir and Doğubeyazıt basins. This pull-apart basin is the result of strike-slip movement along two en-echelon fault segments, the Doğubeyazıt–Gürbulak and Iğdir Faults, of a sinistral strike–slip fault system. Tension between these faults not only formed the original pull-apart basin, but created a system of faults, exhibiting a horsetail splay pattern, that control the position of the principal volcanic eruption centers of Mount Ararat and associated linear belt of parasitic volcanic cones. The strike-slip fault system within which Mount Ararat is located is the result of north–south convergence and tectonic compression between the Arabian Platform and Laurasia that continued after the Tethys Ocean closed during the Eocene epoch along the Bitlis–Zagros suture.


title: Mount Ararat

text: During the early Eocene and early Miocene, the collision of the Arabian platform with Laurasia closed and eliminated the Tethys Ocean from the area of what is now Anatolia. The closure of these masses of continental crust collapsed this ocean basin by middle Eocene and resulted in a progressive shallowing of the remnant seas, until the end of the early Miocene. Post-collisional tectonic convergence within the collision zone resulted in the total elimination of the remaining seas from East Anatolia at the end of early Miocene, crustal shortening and thickening across the collision zone, and uplift of the East Anatolian–Iranian plateau. Accompanying this uplift was extensive deformation by faulting and folding, which resulted in the creation of numerous local basins. The north–south compressional deformation continues today as evidenced by ongoing faulting, volcanism, and seismicity.


title: Mount Ararat

text: Within Anatolia, regional volcanism started in the middle-late Miocene. During the late Miocene–Pliocene period, widespread volcanism blanketed the entire East Anatolian–Iranian plateau under thick volcanic rocks. This volcanic activity has continued uninterrupted until historical times. Apparently, it reached a climax during the latest Miocene–Pliocene, 6 to 3 Ma. During the Quaternary, the volcanism became restricted to a few local volcanoes such as Mount Ararat. These volcanoes are typically associated with north–south tensional fractures formed by the continuing north–south shortening deformation of Anatolia.