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HR 1887
HD 36960 (HR 1887) is a B-type main-sequence star in the constellation Orion. At an apparent magnitude of +4.78 it is easily visible to the naked eye in many areas, though in most urban areas it cannot be seen due to light pollution. Although it does not have a Bayer or Flamsteed designation, it is brighter than over 30 Flamsteed stars in Orion, as well as being brighter than any of the stars in the nearby Orion Nebula such as θ1 Orionis C and θ2 Orionis. HD 36960 forms a close pair with the slightly fainter HD 36959 36" away. Multiple star catalogues also list the 9th magnitude BD-06°1233 as part of the system. HD 36959 is itself a very close binary with a 9th magnitude companion. All these stars are likely members of open cluster NGC 1980 which includes ι Orionis 7' away. At over 15 solar masses, it shines with around 20,000 times the Sun's luminosity due to its high surface temperature of 29,000 K and radius over five times that of the sun. It is cal ... [...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] |
Flamsteed Designation
A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named for John Flamsteed who first used them while compiling his '' Historia Coelestis Britannica''. (Flamsteed used a telescope, and the catalog also includes some stars which are relatively bright but not necessarily visible with the naked eye.) Description Flamsteed designations for stars are similar to Bayer designations, except that they use numbers instead of Greek and Roman letters. Each star is assigned a number and the Latin genitive of the constellation it lies in (see 88 modern constellations for a list of constellations and the genitive forms of their names). Flamsteed designations were assigned to 2554 stars. The numbers were originally assigned in order of increasing right ascension within each constellation, but due to the effects of precession they are now slightly out of o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gould Objects
Gould may refer to: People * Gould (name), a surname Places United States * Gould, Arkansas, a city * Gould, Colorado, an unincorporated community * Gould, Ohio, an unincorporated community * Gould, Oklahoma, a town * Gould, West Virginia, an unincorporated community * Gould City, Michigan * Gould City, Washington * Gould Township, Minnesota Multiple countries * Gould Lake (other) * Mount Gould (other) Elsewhere * Gould (crater), a lunar crater formation * Gould Coast, Antarctica * Gould Dome, Alberta, Canada Other uses * Gould baronets, two titles, one in the Baronetage of England and one in the Baronetage of Great Britain * Gould Belt, a partial ring of stars in the Milky Way * Gould designation, a type of star identifier * Gould League, an independent Australian organisation promoting environmental education * Gould Electronics, a company involved in the electronics and semiconductor industries * Gould Racing, a British motorsport company * USC Go ... [...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 Vachirawit Chiva-aree 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), the eponymous debut from the aforementioned group *Bright (Japanese band), a dance vocal band from Japan ** ''Bright'' (Bright (Japanese band) album) * "Bright" (song), a song b ... [...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] |
B-type Main-sequence Stars
A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type stars are extremely luminous and blue. Their spectra have neutral helium, which are most prominent at the B2 subclass, and moderate hydrogen lines. Examples include Regulus and Algol A. This class of stars was introduced with the Harvard sequence of stellar spectra and published in the ''Revised Harvard photometry'' catalogue. The definition of type B-type stars was the presence of non-ionized helium lines with the absence of singly ionized helium in the blue-violet portion of the spectrum. All of the spectral classes, including the B type, were subdivided with a numerical suffix that indicated the degree to which they approached the next classification. Thus B2 is 1/5 of the way from type B (or B0) to type A. Later, however, more refined s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Mass
The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass of the Sun. This equates to about two nonillion (short scale), two quintillion (long scale) kilograms or 2000 quettagrams: The solar mass is about times the mass of Earth (), or times the mass of Jupiter (). History of measurement The value of the gravitational constant was first derived from measurements that were made by Henry Cavendish in 1798 with a torsion balance. The value he obtained differs by only 1% from the modern value, but was not as precise. The diurnal parallax of the Sun was accurately measured during the transits of Venus in 1761 and 1769, yielding a value of (9 arcseconds, compared to the present value of ). From the value of the diurnal parallax, one can determine the distance to the Sun from the geometry o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iota Orionis
Iota Orionis (ι Orionis, abbreviated ι Ori) is a multiple star system in the equatorial constellation of Orion the hunter. It is the eighth-brightest member of Orion with an apparent visual magnitude of 2.77 and also the brightest member of the asterism known as Orion's Sword. It is a member of the NGC 1980 open cluster. From parallax measurements, it is located at a distance of roughly from the Sun. The system has three visible components designated Iota Orionis A, B and C. Iota Orionis A has also been resolved using speckle interferometry and is also a massive spectroscopic binary, with components Iota Orionis Aa1 (officially named Hatysa ), Aa2, and Ab. Nomenclature ''ι Orionis'' ( Latinised to ''Iota Orionis'') is the system's Bayer designation. The designations of the three constituents as ''Iota Orionis A'', ''B'' and ''C'', and those of ''A's'' components - ''Iota Orionis Aa1'', ''Aa2'', and ''Ab'' - derive from the convention used by the Washing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 1980
NGC 1980 (also known as OCL 529, Collinder 72 and The Lost Jewel of Orion) is a young open cluster associated with an emission nebula in the constellation Orion. It was discovered by William Herschel Frederick William Herschel (; german: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline ... on 31 January 1786. Its apparent size is 14 × 14 arc minutes and it is located around the star Iota Orionis on the southern tip of the Orion constellation. Herschel made his first observation of the cluster which was called WH V 31 on 31 January 1786, but he possibly observed it during his studies of double stars on 20 September 1783. References Open clusters Orion molecular cloud complex 1980 Orion (constellation) Astronomical objects discovered in 1783 Discoveries by William Herschel Orion–Cygnus Arm {{star-clu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open Cluster
An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. They are loosely bound by mutual gravity, gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center. This can result in a migration to the main body of the galaxy and a loss of cluster members through internal close encounters. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral galaxy, spiral and irregular galaxy, irregular galaxies, in which active star formation is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theta2 Orionis
Theta2 Orionis (θ2 Ori) is a multiple star system in the constellation Orion. It is a few arc minutes from its more famous neighbour the Trapezium Cluster, also known as θ1 Orionis. Components θ2 Orionis consists of three stars in a line, each about an arc-minute from the next. In addition to the well-known three stars, the Washington Double Star Catalog confusingly lists a component D which is actually θ1 Orionis C. There is one other star brighter than 10th magnitude in the region. V1073 Orionis is a B9.5 Orion variable that forms an equilateral triangle with θ2 Ori B and C. Bizarrely, θ2 Orionis C has a second entry in the Washington Double Star Catalog under the name S490. The companion is 10th magnitude and actually lies between θ2 Ori B and V1073 Ori. θ1 Orionis, the well known Trapezium cluster, is only 2 arc minutes away from θ2 Orionis A. Despite the names, θ2 Orionis A is marginally brighter than the brightest star in the Trapezium. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
