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109 Herculis
109 Herculis is a single star in the northern constellation of Hercules. It is visible to the naked eye as a faint, orange-hued point of light with an apparent visual magnitude of 3.84. The star is located around distant, based on parallax. It is moving closer to the Earth with a heliocentric radial velocity of −58 km/s, and may come as close as away in around 328,000 years. This is an aging giant star with a stellar classification of K2IIIab. It is a red clump giant, meaning it on the horizontal branch and is generating energy through helium fusion at its core. The star is roughly six billion years old with slightly more mass than the Sun. With the supply of hydrogen at its core exhausted, it has expanded to nearly 12 times the Sun's radius. The star is radiating 57 times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,569 K. This star, together with 93 Her, 95 Her, and 102 Her, were consist Cerberus In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminosity Of The Sun
The solar luminosity (), is a unit of radiant flux (power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun. One nominal solar luminosity is defined by the International Astronomical Union to be . This does not include the solar neutrino luminosity, which would add , or , i.e. a total of (the mean energy of the solar photons is 26 MeV and that of the solar neutrinos 0.59 MeV, i.e. 2.27%; the Sun emits photons and as many neutrinos each second, of which per m2 reach the Earth each second). The Sun is a weakly variable star, and its actual luminosity therefore fluctuates. The major fluctuation is the eleven-year solar cycle (sunspot cycle) that causes a quasi-periodic variation of about ±0.1%. Other variations over the last 200–300 years are thought to be much smaller than this. Determination Solar luminosity is related to solar irradiance (the solar c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Draper Catalogue Objects
Henry may refer to: People *Henry (given name) *Henry (surname) * Henry Lau, Canadian singer and musician who performs under the mononym Henry Royalty * Portuguese royalty ** King-Cardinal Henry, King of Portugal ** Henry, Count of Portugal, Henry of Burgundy, Count of Portugal (father of Portugal's first king) ** Prince Henry the Navigator, Infante of Portugal ** Infante Henrique, Duke of Coimbra (born 1949), the sixth in line to Portuguese throne * King of Germany ** Henry the Fowler (876–936), first king of Germany * King of Scots (in name, at least) ** Henry Stuart, Lord Darnley (1545/6–1567), consort of Mary, queen of Scots ** Henry Benedict Stuart, the 'Cardinal Duke of York', brother of Bonnie Prince Charlie, who was hailed by Jacobites as Henry IX * Four kings of Castile: **Henry I of Castile **Henry II of Castile **Henry III of Castile **Henry IV of Castile * Five kings of France, spelt ''Henri'' in Modern French since the Renaissance to italianize the name and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flamsteed Objects
John Flamsteed (19 August 1646 – 31 December 1719) was an English astronomer and the first Astronomer Royal. His main achievements were the preparation of a 3,000-star catalogue, ''Catalogus Britannicus'', and a star atlas called ''Atlas Coelestis'', both published posthumously. He also made the first recorded observations of Uranus, although he mistakenly catalogued it as a star, and he laid the foundation stone for the Royal Greenwich Observatory. Life Flamsteed was born in Denby, Derbyshire, England, the only son of Stephen Flamsteed and his first wife, Mary Spadman. He was educated at the free school of Derby and at Derby School, in St Peter's Churchyard, Derby, near where his father carried on a malting business. At that time, most masters of the school were Puritans. Flamsteed had a solid knowledge of Latin, essential for reading the scientific literature of the day, and a love of history, leaving the school in May 1662.Birks, John L. (1999) ''John Flamsteed, the f ... [...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, compiled by the Bonn Observatory in Germany from 1859 to 1903. 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 wavelengths shorter or longer than visible light waves. Original catalog The 44 years of work on the Bonner Durchmusterung (abbreviated BD), initiated by Friedrich Argelander and largely carried out by his assistants, resulted in a catalogue of the positions and apparent magnitudes of approximately 325,000 stars to apparent magnitude 9–10. The catalogue was accompanied by charts plotting the positions of the stars, and was the basis for the ''Astronomische Gesellschaft Katalog'' (AGK) and ''Smithsonia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horizontal-branch Stars
The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red-giant branch in stars whose masses are similar to the Sun's. Horizontal-branch stars are powered by helium fusion in the core (via the triple-alpha process) and by hydrogen fusion (via the CNO cycle) in a shell surrounding the core. The onset of core helium fusion at the tip of the red-giant branch causes substantial changes in stellar structure, resulting in an overall reduction in luminosity, some contraction of the stellar envelope, and the surface reaching higher temperatures. Discovery Horizontal branch stars were discovered with the first deep photographic photometric studies of globular clusters and were notable for being absent from all open clusters that had been studied up to that time. The horizontal branch is so named because in low-metallicity star collections like globular clusters, HB stars lie along a roughly horizontal line in a Hertzsprung–Russell diagram. Because the sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K-type Giants , an unusual kind of asteroid
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K-type may refer to: *AEC K-type, a bus chassis *K-type star, a stellar spectral classification *K-type filter, a type of electronic filter *K-type asteroid K-type asteroids are relatively uncommon asteroids with a moderately reddish spectrum shortwards of 0.75 μm, and a slight bluish trend longwards of this. They have a low albedo. Their spectrum resembles that of CV and CO meteorites. A larger K t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monthly Notices Of The Royal Astronomical Society
''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes letters and papers reporting original research in relevant fields. Despite the name, the journal is no longer monthly, nor does it carry the notices of the Royal Astronomical Society. History The first issue of MNRAS was published on 9 February 1827 as ''Monthly Notices of the Astronomical Society of London'' and it has been in continuous publication ever since. It took its current name from the second volume, after the Astronomical Society of London became the Royal Astronomical Society (RAS). Until 1960 it carried the monthly notices of the RAS, at which time these were transferred to the newly established ''Quarterly Journal of the Royal Astronomical Society'' (1960–1996) and then to its successor journal ''Astronomy & Geophysics'' (since 1997). Until 1965, MNRAS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerberus (constellation)
Cerberus is an obsolete constellation created by Hevelius in the 1600s, whose stars are now included in the constellation Hercules. It was depicted as a three-headed snake that Hercules is holding in his hand. The constellation is no longer in use. This constellation "figure typified the serpent ... infesting the country around Taenarum the Μέτωπον of Greece, the modern Cape Matapan." The presence of Cerberus (Kerberos) at Taenarum (Tainaron) is mentioned by Strabo, Statius, and Seneca the Younger. John Senex combined this constellation with the likewise obsolete constellation Ramus Pomifer Ramus Pomifer (Latin for ''apple branch'') was a constellation between Hercules and Lyra. It was depicted in the form of a branch held in Hercules' left hand. The also-obsolete constellation of Cerberus In Greek mythology, Cerberus (; gr ..., an apple branch held by Hercules, in his 1721 star map to create "Cerberus et Ramus". Notes External links Ian Ridpath's Star Tales: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
102 Herculis
102 Herculis is a single star in the northern constellation of Hercules. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.37. Based upon parallax measurements, it is located around 920 light years away from the Sun. The star is moving closer to the Earth with a heliocentric radial velocity of −15 km/s. The stellar classification of this object matches a massive, early B-type star with a luminosity class of IV or V, corresponding to a subgiant or main sequence star, respectively. It is 20 million years old with nearly ten times the mass of the Sun and is spinning with a projected rotational velocity of 41 km/s. The strength of the stellar magnetic field has been measured at . The star is radiating 3,632 times the Sun's luminosity from its photosphere at an effective temperature of 22,420 K. Etymology In Chinese Chinese can refer to: * Something related to China * Chinese people, peopl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
95 Herculis
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95 or 95th may refer to: * 95 (number) * one of the years 95 BC, AD 95, 1995, 2095, etc. * 95th Division (other) * 95th Regiment ** 95th Regiment of Foot (other) * 95th Squadron (other) * Atomic number 95: americium * Microsoft Office 95 * Saab 95 * Windows 95 See also * 9 to 5 (other) * * List of highways numbered A ''list'' is any set of items in a row. List or lists may also refer to: People * List (surname) Organizations * List College, an undergraduate division of the Jewish Theological Seminary of America * SC Germania List, German rugby union ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
93 Herculis
93 Herculis is a star located around 750 light years away from the Sun in the northern constellation of Hercules. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.67 The brightness of the star is diminished by an extinction of 0.21 due to interstellar dust. It is moving closer to the Earth with a heliocentric radial velocity of −24.5 km/s. This star, together with 95 Her, 102 Her, and 109 Her, made up the obsolete constellation Cerberus. This object has a stellar classification of K0.5IIb, which indicates it is an evolved bright giant. With the supply of hydrogen at its core exhausted, the star has expanded to 51 times the Sun's radius. It is radiating around 919 times the luminosity of the Sun from its enlarged photosphere at an effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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