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F-type Main-sequence Stars
An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII and VIII. This temperature range gives the F-type stars a whitish hue when observed by the atmosphere. Because a main-sequence star is referred to as a dwarf star, this class of star may also be termed a yellow-white dwarf (not to be confused with white dwarfs, remnant stars that are a possible final stage of stellar evolution). Notable examples include Procyon A, Gamma Virginis A and B, and KIC 8462852. Spectral standard stars The revised Yerkes Atlas system (Johnson & Morgan 1953) listed a dense grid of F-type dwarf spectral standard stars; however, not all of these have survived to this day as stable standards. The ''anchor points'' of the MK spectral classification system among the F-type main-sequence dwarf stars, i.e. thos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Insights Into Debris Discs
New or NEW may refer to: Music * New, singer of K-pop group The Boyz (South Korean band), The Boyz * New (album), ''New'' (album), by Paul McCartney, 2013 ** New (Paul McCartney song), "New" (Paul McCartney song), 2013 * New (EP), ''New'' (EP), by Regurgitator, 1995 * New (Daya song), "New" (Daya song), 2017 * New (No Doubt song), "New" (No Doubt song), 1999 * "new", a song by Loona from the 2017 single album ''Yves (single album), Yves'' * "The New", a song by Interpol from the 2002 album ''Turn On the Bright Lights'' Transportation * Lakefront Airport, New Orleans, U.S., IATA airport code NEW * Newcraighall railway station, Scotland, station code NEW Other uses * New (film), ''New'' (film), a 2004 Tamil movie * New (surname), an English family name * NEW (TV station), in Australia * new and delete (C++), in the computer programming language * Net economic welfare, a proposed macroeconomic indicator * Net explosive weight, also known as net explosive quantity * Network of enlig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminosity
Luminosity is an absolute measure of radiated electromagnetic radiation, electromagnetic energy per unit time, and is synonymous with the radiant power emitted by a light-emitting object. In astronomy, luminosity is the total amount of electromagnetic energy emitted per unit of time by a star, galaxy, or other astronomical object, astronomical objects. In SI units, luminosity is measured in joules per second, or watts. In astronomy, values for luminosity are often given in the terms of the Solar luminosity, luminosity of the Sun, ''L''⊙. Luminosity can also be given in terms of the astronomical Magnitude (astronomy), magnitude system: the Absolute magnitude#Bolometric magnitude, absolute bolometric magnitude (''M''bol) of an object is a logarithmic measure of its total energy emission rate, while absolute magnitude is a logarithmic measure of the luminosity within some specific wavelength range or Passband, filter band. In contrast, the term ''brightness'' in astronomy is gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 27534
HD may refer to: Business * H-D or Harley-Davidson, a motorcycle manufacturer * The Home Depot, NYSE stock symbol: HD Chemistry * Hydrogen deuteride, a diatomic compound of hydrogen and deuterium * Mustard gas Codes * Air Do, formerly Hokkaido International Airlines, IATA designator * HD postcode area, covering Huddersfield, Brighouse and Holmfirth in England, UK * Heidelberg's vehicle registration plate code * Hunedoara County (Romania)'s ISO 3166 code Medicine * Hansen's disease or leprosy * Hirschsprung's disease, a disorder of the abdomen * Huntington's disease, a genetic disorder affecting the central nervous system ** HD (gene) or huntingtin, the IT15 gene, which codes for the huntingtin protein People * H.D. or Hilda Doolittle (1886–1961), American poet and novelist Other uses * ''Helsingborgs Dagblad'', a Swedish newspaper * Henry Draper Catalogue, an astronomical catalogue often used to designate stars * Department of Highways (other) * ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Virginis
Beta Virginis, a name Latinised from β Virginis, is a star in the equatorial constellation of Virgo. It has the proper name Zavijava (), and, despite its designation 'beta', is the fifth-brightest star in Virgo with an apparent visual magnitude of 3.604. The distance to this star is around 35.7 light-years based on parallax; it is drifting further away with a radial velocity of +4.1 km/s. It is 0.69 of a degree north of the ecliptic, so it can be occulted by the Moon and (rarely) by planets. The next planetary occultation of Beta Virginis will take place on 9 November 2210, by Venus; although an occultation by the same planet might be visible on 11 August 2069 from the South Pole. Properties This is an F-type main-sequence star with a stellar classification of F9 V, which means it is generating energy through core hydrogen fusion. Sun-like oscillations have been detected in Beta Virginis, allowing its internal structure to be modeled in more detail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 27383
HD may refer to: Business * H-D or Harley-Davidson, a motorcycle manufacturer * The Home Depot, NYSE stock symbol: HD Chemistry * Hydrogen deuteride, a diatomic compound of hydrogen and deuterium * Mustard gas Codes * Air Do, formerly Hokkaido International Airlines, IATA designator * HD postcode area, covering Huddersfield, Brighouse and Holmfirth in England, UK * Heidelberg's vehicle registration plate code * Hunedoara County (Romania)'s ISO 3166 code Medicine * Hansen's disease or leprosy * Hirschsprung's disease, a disorder of the abdomen * Huntington's disease, a genetic disorder affecting the central nervous system ** HD (gene) or huntingtin, the IT15 gene, which codes for the huntingtin protein People * H.D. or Hilda Doolittle (1886–1961), American poet and novelist Other uses * ''Helsingborgs Dagblad'', a Swedish newspaper * Henry Draper Catalogue, an astronomical catalogue often used to designate stars * Department of Highways (other) * ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pi3 Orionis
Pi3 Orionis (π3 Orionis, abbreviated Pi3 Ori, π3 Ori), also named Tabit , is a star in the equatorial constellation of Orion. At an apparent visual magnitude of 3.16, it is readily visible to the naked eye and is the brightest star in the lion's hide (or shield) that Orion is holding. As measured using the parallax technique, it is distant from the Sun. Nomenclature ''π3 Orionis'' ( Latinised to ''Pi3 Orionis'') is the system's Bayer designation. It bore the traditional name of 'Tabit', from the Arabic الثابت ''al-thābit'' 'the endurer (the fixed/constant one)'. In 2016, the IAU organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN approved the name ''Tabit'' for this star on 5 September 2017 and it is now so included in the List of IAU-approved Star Names. In Chinese, (), meaning '' Banner of Three Stars'', refers to an asterism consisting of π3 Orionis, ο1 Orionis, ο2 Orionis, 6 Orionis, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
78 Ursae Majoris
78 Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major. It is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.93. Parallax estimates by Hipparcos put it at a distance of , but it is drifting closer with a radial velocity of −5 km/s. The system is a candidate member of the Ursa Major Moving Group. The binary nature of this system was announced by S. W. Burnham in 1894. The pair orbit each other with a period of 105 years and an eccentricity of 0.39. Their semimajor axis has an angular size of and the orbital plane is inclined by 47°. The primary member, designated component A, has a magnitude of 5.02 and is an F-type main-sequence star with a stellar classification of F2V. It is 785 million years old and is spinning with a projected rotational velocity of 92 km/s. The star has 1.34 times the mass of the Sun and is radiating 5.75 times the Sun's luminosi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
