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A Centauri (other)
The Bayer designations A Centauri and a Centauri represent different stars. Due to technical limitations, both designations link here. * A Centauri, HD 100673, a main sequence star * a Centauri, V761 Centauri, a variable star See also * α Centauri, Alpha Centauri ** α1 Centauri, Alpha Centauri A (HD 128620) ** α2 Centauri, Alpha Centauri B (HD 128621) * Alpha Centauri (other) * 1 Centauri 1 Centauri, or i Centauri, is a yellow-white-hued binary star system in the southern constellation Centaurus. It can be seen with the naked eye, having an apparent visual magnitude of +4.23. Based upon an annual parallax shift of 51 ... {{sia Centauri, a Centaurus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. The brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas ''Uranometria''. Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers (including Nicolas-Louis de Lacaille and Benjamin Apthorp Gould) supplemented Bayer's catalog with entries for southern constellations. Scheme Bayer assigned a lowercase Greek letter (alpha (α), beta (β), gamma (γ), etc.) or a Latin letter (A, b, c, etc.) to each star he catalogued, combined with the Latin name of the star's parent constellation in genitive (possessive) form. The constellation name is frequently abbreviated to a standard three-letter form. For example, Aldebaran in the constellation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 100673
A Centauri is a single star in the southern constellation of Centaurus. It is blue-white in hue and is faintly visible to the naked eye with an apparent visual magnitude of +4.62. The star is located at a distance of approximately 430 light-years from the Sun based on stellar parallax. It appears to be drifting further away with a radial velocity of around +6 km/s. This is a rapidly rotating Be star, showing an emission-line spectrum on top of the normal absorption spectrum of the star, due to a circumstellar disk of ejected matter. It doesn't show any absorption lines from the disk. It is a B-type main-sequence star with a stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ... of B9V. References External links *Wikiskimageof HD 100673 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or dwarf stars. These are the most numerous true stars in the universe and include the Sun. After condensation and ignition of a star, it generates thermal energy in its dense core region through nuclear fusion of hydrogen into helium. During this stage of the star's lifetime, it is located on the main sequence at a position determined primarily by its mass but also based on its chemical composition and age. The cores of main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V761 Centauri
HD 125823, also known as V761 Centauri or a Centauri, is a variable star in the constellation Centaurus. It is a blue-white star that is visible to the naked eye with a mean apparent visual magnitude of +4.41. The distance to this star is approximately 460 light years based on parallax measurements. It is a member of the Upper Centaurus–Lupus subgroup of the Scorpius–Centaurus association. In 1965, W. P. Bidelman discovered that the intensities of the star's neutral helium lines had varied on photographic plates taken over the period 1908 to 1911. This variation was confirmed by A. D. Thackeray in 1966. The star ranges from a helium-strong B2 class to a helium-weak B8 with a period of 8.82 days. Radial velocity measurements during the 1970s showed differing velocity variations for helium and other elements. The magnetic field strength peaks at a negative maximum in phase with the maximum helium line strength. Weak emission has been detected in the singly-i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable Star
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as either: * Intrinsic variables, whose luminosity actually changes; for example, because the star periodically swells and shrinks. * Extrinsic variables, whose apparent changes in brightness are due to changes in the amount of their light that can reach Earth; for example, because the star has an orbiting companion that sometimes eclipses it. Many, possibly most, stars have at least some variation in luminosity: the energy output of the Sun, for example, varies by about 0.1% over an 11-year solar cycle. Discovery An ancient Egyptian calendar of lucky and unlucky days composed some 3,200 years ago may be the oldest preserved historical document of the discovery of a variable star, the eclipsing binary Algol. Of the modern astronomers, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Centauri
Alpha Centauri ( Latinized from α Centauri and often abbreviated Alpha Cen or α Cen) is a triple star system in the constellation of Centaurus. It consists of 3 stars: Alpha Centauri A (officially Rigil Kentaurus), Alpha Centauri B (officially Toliman) and Alpha Centauri C (officially Proxima Centauri). Proxima Centauri is also the closest star to the Sun at 4.2465 light-years (1.3020 pc). Alpha Centauri A and B are Sun-like stars ( Class G and K, respectively), and together they form the binary star system Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of −0.27. It is the brightest star in the constellation and the third-brightest in the night sky, outshone only by Sirius and Canopus. Alpha Centauri A has 1.1 times the mass and 1.5 times the luminosity of the Sun, while Alpha Centauri B is smaller and cooler, at 0.9 times the Sun's mass and less than 0.5 times its luminosity. The pair or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Centauri A
Alpha Centauri (Latinisation of names, Latinized from α Centauri and often abbreviated Alpha Cen or α Cen) is a Star System, triple star system in the constellation of Centaurus (constellation), Centaurus. It consists of 3 stars: Alpha Centauri A (officially Rigil Kentaurus), Alpha Centauri B (officially Toliman) and Alpha Centauri C (officially Proxima Centauri). Proxima Centauri is also the closest star to the Sun at 4.2465 Light-year, light-years (1.3020 Parsec, pc). Alpha Centauri A and B are Sun-like stars (G-type main-sequence star, Class G and K-type main-sequence star, K, respectively), and together they form the binary star system Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of −0.27. It is the brightest star in the constellation and the List of brightest stars, third-brightest in the night sky, outshone only by Sirius and Canopus. Alpha Centauri A has 1.1 times the stellar mass, mas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Centauri B
Alpha Centauri ( Latinized from α Centauri and often abbreviated Alpha Cen or α Cen) is a triple star system in the constellation of Centaurus. It consists of 3 stars: Alpha Centauri A (officially Rigil Kentaurus), Alpha Centauri B (officially Toliman) and Alpha Centauri C (officially Proxima Centauri). Proxima Centauri is also the closest star to the Sun at 4.2465 light-years (1.3020 pc). Alpha Centauri A and B are Sun-like stars ( Class G and K, respectively), and together they form the binary star system Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of −0.27. It is the brightest star in the constellation and the third-brightest in the night sky, outshone only by Sirius and Canopus. Alpha Centauri A has 1.1 times the mass and 1.5 times the luminosity of the Sun, while Alpha Centauri B is smaller and cooler, at 0.9 times the Sun's mass and less than 0.5 times its luminosity. The pair orbi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Centauri (other)
Alpha Centauri (or α Cen) is a star system and the collective name of three stars in that system. The individual stars are named Alpha Centauri A, Alpha Centauri B, and Proxima Centauri. Alpha Centauri may also refer to: * Alpha Centauri (Doctor Who), an alien in ''Doctor Who'' * Alpha Centauri (horse) (foaled 2015), Irish-trained thoroughbred racehorse * ''Sid Meier's Alpha Centauri'', a 1999 strategy computer game * ''Alpha Centauri'' (album), an album by Tangerine Dream * "Alpha Centauri", a song by At the Drive-In from ''In/Casino/Out'' * "Alpha Centauri", a song by Peter Ivers from '' Terminal Love'' * The Alpha Centaurids, a meteor shower See also * A Centauri (other) * Alpha Centauri b (other) * Alpha Centauri in fiction * * Centauri (other) * Alpha (other) Alpha ( or ) is the first letter of the Greek alphabet. Alpha or ALPHA may also refer to: Letters * Latin alpha (), a letter of the Latin alphabet * , a glyph in the Intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1 Centauri
1 Centauri, or i Centauri, is a yellow-white-hued binary star system in the southern constellation Centaurus. It can be seen with the naked eye, having an apparent visual magnitude of +4.23. Based upon an annual parallax shift of 51.54 mas as seen from Earth's orbit, it is located 51.5 light-years from the Sun. The system is moving closer to the Sun with a radial velocity of −21.5 km/s. Spectrographic images taken at the Cape Observatory between 1921 and 1923 showed this star has a variable radial velocity, which indicated this is a single-lined spectroscopic binary star system. The pair have an orbital period of 9.94 days and an eccentricity of about 0.2. The primary component has received a number of different stellar classifications. For example, Jaschek et al. (1964) lists F0V, F2III, F4III and F4IV, thus ranging in evolutionary state from an ordinary F-type main-sequence star to a giant star. More recently, Houk (1982) listed a class of F3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Objects
Bayer AG (, commonly pronounced ; ) is a German multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of business include pharmaceuticals; consumer healthcare products, agricultural chemicals, seeds and biotechnology products. The company is a component of the Euro Stoxx 50 stock market index. Bayer was founded in 1863 in Barmen as a partnership between dye salesman Friedrich Bayer and dyer Friedrich Weskott. As was common in this era, the company was established as a dyestuffs producer. The versatility of aniline chemistry led Bayer to expand their business into other areas, and in 1899 Bayer launched the compound acetylsalicylic acid under the trademarked name Aspirin. In 1904 Bayer received a trademark for the "Bayer Cross" logo, which was subsequently stamped onto each aspirin tablet, creating an iconic product that is still sold by Bayer. Other commonly known produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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