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V473 Lyrae
V473 Lyrae is a variable star in the constellation Lyra. It is an unusual Classical Cepheid variable with a visual range of 5.99 to 6.35. Discovery V473 Lyrae is a faint naked eye star, but its brightness variations were not reported until 1968. It was noted to be possibly variable, then examined as a possible Delta scuti variable, δ Sct variable. It was confirmed as variable but the variations were considered semi-regular and so it was not catalogued as a δ Sct variable. In 1979, brightness variations were again noticed and V473 was listed as a short-period Cepheid, although the period was thought to be 3.04 days. The correct period was found a few years later at 1.49078 days, at the time the shortest known period for a galactic Cepheid. Unusual periodic variations in the pulsation amplitude were also noticed, similar to the Blazhko effect in RR Lyrae variables. Pulsations The unusually short period of V473 Lyr is caused by pulsations in the second overtone and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyra
, from ; pronounced: ) is a small constellation. It is one of the 48 listed by the 2nd century astronomer Ptolemy, and is one of the modern 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence is sometimes referred to as Vultur Cadens or Aquila Cadens ("Falling Vulture" or "Falling Eagle"), respectively. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is nearly overhead in temperate northern latitudes shortly after midnight at the start of summer. From the equator to about the 40th parallel south it is visible low in the northern sky during the same (thus winter) months. Vega, Lyra's brightest star, is one of the brightest stars in the night sky, and forms a corner of the famed Summer Triangle asterism. Beta Lyrae is the prototype of a class of binary stars known as Beta Lyrae variables. These binary stars are so close to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classical Cepheid Variables
Classical Cepheids are a type of Cepheid variable star. They are young, population I variable stars that exhibit regular radial pulsations with periods of a few days to a few weeks and visual amplitudes ranging from a few tenths of a magnitude up to about 2 magnitudes. Classical Cepheids are also known as Population I Cepheids, Type I Cepheids, and Delta Cepheid variables. There exists a well-defined relationship between a classical Cepheid variable's luminosity and pulsation period, securing Cepheids as viable standard candles for establishing the galactic and extragalactic distance scales. Hubble Space Telescope (HST) observations of classical Cepheid variables have enabled firmer constraints on Hubble's law, which describes the expansion rate of the observable Universe. Classical Cepheids have also been used to clarify many characteristics of our galaxy, such as the local spiral arm structure and the Sun's distance from the galactic plane. Around 3,600 classical Cepheids ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bright Star Catalogue Objects
Bright may refer to: Common meanings *Bright, an adjective meaning giving off or reflecting illumination; see Brightness *Bright, an adjective meaning someone with intelligence People * Bright (surname) * Bright (given name) *Bright, the stage name of Thai actor, musician, model, host and entrepreneur Vachirawit Chivaaree Places Australia * Bright, Victoria, a town * Electoral district of Bright in South Australia Canada * Bright Parish, New Brunswick Northern Ireland * Bright, County Down, a village and parish in County Down United States * Bright, Indiana, a census-designated place * Bright, West Virginia, an unincorporated community * Bright, Wisconsin, an unincorporated community Arts and entertainment Music * Bright (American band), an experimental pop group from Brooklyn, New York ** ''Bright'' (Bright (American band) album), 1996 album * Bright (Japanese band), a dance vocal band from Japan ** ''Bright'' (Bright (Japanese band) album), 2012 album * "Bright" (song), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Draper Catalogue Objects
Henry may refer to: People and fictional characters * Henry (given name), including lists of people and fictional characters * Henry (surname) * Henry, a stage name of François-Louis Henry (1786–1855), French baritone Arts and entertainment * Henry (2011 film), ''Henry'' (2011 film), a Canadian short film * Henry (2015 film), ''Henry'' (2015 film), a virtual reality film * ''Henry: Portrait of a Serial Killer'', a 1986 American crime film * Henry (comics), ''Henry'' (comics), an American comic strip created in 1932 by Carl Anderson * "Henry", a song by New Riders of the Purple Sage Places Antarctica * Henry Bay, Wilkes Land Australia *Henry River (New South Wales) *Henry River (Western Australia) Canada * Henry Lake (Vancouver Island), British Columbia * Henry Lake (Halifax County), Nova Scotia * Henry Lake (District of Chester), Nova Scotia New Zealand * Lake Henry (New Zealand) * Henry River (New Zealand) United States * Henry, Illinois * Henry, Indiana * Henry, Nebras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durchmusterung Objects
In astronomy, Durchmusterung or Bonner Durchmusterung (BD) is an astrometric star catalogue of the whole sky, published by the Bonn Observatory in Germany from 1859 to 1863, with an extension published in Bonn in 1886. The name comes from ('run-through examination'), a German word used for a systematic survey of objects or data. The term has sometimes been used for other astronomical surveys, including not only stars, but also the search for other celestial objects. Special tasks include celestial scanning in electromagnetic spectrum, electromagnetic wavelengths shorter or longer than visible light waves. Original catalog The Bonner Durchmusterung (abbreviated BD), was initiated by Friedrich Wilhelm Argelander, Friedrich Argelander and using observations largely carried out by his assistants, which resulted in a catalogue of the positions and apparent magnitudes of 342,198 stars down to approximate apparent magnitude 9.5 and covering the sky from 90°N to 2°S declination. The cat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Objects With Variable Star Designations
Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an aim, target, or objective * Object (grammar), a sentence element, such as a direct object or an indirect object Science, technology, and mathematics Computing * 3D model, a representation of a physical object * Object (computer science), a language mechanism for binding data with methods that operate on that data ** Object-orientation (other), in which concepts are represented as objects *** Object-oriented programming (OOP), in which an object is an instance of a class or array ** Object (IBM i), the fundamental unit of data storage in the IBM i operating system * Object file, the output of a compiler or other translator program (also known as "object code") * HTML object element Mathematics * Object (mathematics), an abst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-type Bright Giants
F-type may refer to: *F-type asteroid, a type of carbonaceous asteroid *F-ATPase, a membrane protein *F-type main-sequence star, a hydrogen-fusing star *F-type Prisons, high-security prisons in Turkey *MG F-type Magna, six-cylinder-engined car produced by the MG Car company from October 1931 to 1932 *Jaguar F-Type, a two-seat sports car manufactured by Jaguar Cars *Renault F-Type engine, straight-4 automobile engine from Renault *Empire F type coaster, a type of prefabricated coastal tanker built in the UK during the Second World War *F connector, a commonly used connector for coaxial cable *F type Adelaide tram Type F may refer to: *AC power plugs and sockets#Type F, Type F AC power plugs and sockets *the Avro Type F, an aircraft *Tightlock_coupling#AAR_Type_F, Type-F couplers in rail transport *a Type F submarine *the Handley Page Type F, an aircraft *the Caudron Type F, a biplane *the Deronda Type F, a performance car See also *F class (other) *B type (disambiguati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ranging from 10 Nanometre, nanometers to 10 Picometre, picometers, corresponding to frequency, frequencies in the range of 30 Hertz, petahertz to 30 Hertz, exahertz ( to ) and photon energies in the range of 100 electronvolt, eV to 100 keV, respectively. X-rays were discovered in 1895 in science, 1895 by the German scientist Wilhelm Röntgen, Wilhelm Conrad Röntgen, who named it ''X-radiation'' to signify an unknown type of radiation.Novelline, Robert (1997). ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. . X-rays can penetrate many solid substances such as construction materials and living tissue, so X-ray radiography is widely used in medical diagnostics (e.g., checking for Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Unit
The astronomical unit (symbol: au or AU) is a unit of length defined to be exactly equal to . Historically, the astronomical unit was conceived as the average Earth-Sun distance (the average of Earth's aphelion and perihelion), before its modern redefinition in 2012. The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec. One au is approximately equivalent to 499 light-seconds. History of symbol usage A variety of unit symbols and abbreviations have been in use for the astronomical unit. In a 1976 resolution, the International Astronomical Union (IAU) had used the symbol ''A'' to denote a length equal to the astronomical unit. In the astronomical literature, the symbol AU is common. In 2006, the International Bureau of Weights and Measures (BIPM) had recommended ua as the symbol for the unit, from the French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overtone
An overtone is any resonant frequency above the fundamental frequency of a sound. (An overtone may or may not be a harmonic) In other words, overtones are all pitches higher than the lowest pitch within an individual sound; the fundamental is the lowest pitch. While the fundamental is usually heard most prominently, overtones are actually present in any pitch except a true sine wave. The relative volume or amplitude of various overtone partials is one of the key identifying features of timbre, or the individual characteristic of a sound. Using the model of Fourier analysis, the fundamental and the overtones together are called Harmonic series (music)#Partial, partials. Harmonics, or more precisely, harmonic partials, are partials whose frequencies are numerical integer multiples of the fundamental (including the fundamental, which is 1 times itself). These overlapping terms are variously used when discussing the acoustic behavior of musical instruments.Alexander John Ellis, A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RR Lyrae Variable
RR Lyrae variables are periodic variable stars, commonly found in globular clusters. They are used as standard candles to measure (extra) galactic distances, assisting with the cosmic distance ladder. This class is named after the prototype and brightest example, RR Lyrae. They are pulsating horizontal branch stars of spectral class A or F, with a mass of around half the Sun's. They are thought to have shed mass during the red-giant branch phase, and were once stars at around 0.8 solar masses. In contemporary astronomy, a period-luminosity relation makes them good standard candles for relatively nearby targets, especially within the Milky Way and Local Group. They are also frequent subjects in the studies of globular clusters and the chemistry (and quantum mechanics) of older stars. Discovery and recognition In surveys of globular clusters, these "cluster-type" variables were being rapidly identified in the mid-1890s, especially by E. C. Pickering. Probably the fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
