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Tucana (Chinese Astronomy)
The modern constellation Tucana is not included in the Three Enclosures and Twenty-Eight Mansions system of traditional Traditional Chinese star names#Categories of Chinese traditional uranography, Chinese uranography because its stars are too far south for observers in China to know about them prior to the introduction of Western star charts. Based on the work of Xu Guangqi and the German Jesuit missionary Johann Adam Schall von Bell in the late Ming Dynasty, this constellation has been classified as one of the 23 Chinese constellations#The Southern Asterisms (近南極星區), Southern Asterisms (近南極星區, ''Jìnnánjíxīngōu'') under the name Chinese constellations#The Southern Asterisms (近南極星區), Crane (鶴, ''Hè'') and Chinese constellations#The Southern Asterisms (近南極星區), Bird's Beak (鳥喙, ''Niǎohuì''). The name of the western constellation in modern Chinese is 杜鵑座 (''dù juān zuò''), meaning "the cuckoo constellation". Stars The map o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tucana
Tucana (The Toucan) is a constellation of stars in the southern sky, named after the toucan, a South American bird. It is one of twelve constellations conceived in the late sixteenth century by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman. Tucana first appeared on a celestial globe published in 1598 in Amsterdam by Plancius and Jodocus Hondius and was depicted in Johann Bayer's star atlas ''Uranometria'' of 1603. French explorer and astronomer Nicolas Louis de Lacaille gave its stars Bayer designations in 1756. The constellations Tucana, Grus, Phoenix and Pavo are collectively known as the "Southern Birds". Tucana is not a prominent constellation as all of its stars are third magnitude or fainter; the brightest is Alpha Tucanae with an apparent visual magnitude of 2.87. Beta Tucanae is a star system with six member stars, while Kappa is a quadruple system. Five star systems have been found to have exoplanets to date. The const ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Astronomy
Astronomy in China has a long history stretching from the Shang dynasty, being refined over a period of more than 3,000 years. The ancient Chinese people have identified stars from 1300 BCE, as Chinese star names later categorized in the twenty-eight mansions have been found on oracle bones unearthed at Anyang, dating back to the mid-Shang dynasty. The core of the "mansion" (宿 ''xiù'') system also took shape around this period, by the time of King Wu Ding (1250–1192 BCE). Detailed records of astronomical observations began during the Warring States period (fourth century BCE) and flourished from the Han period onward. Chinese astronomy was equatorial, centered on close observation of circumpolar stars, and was based on different principles from those in traditional Western astronomy, where heliacal risings and settings of zodiac constellations formed the basic ecliptic framework. Joseph Needham has described the ancient Chinese as the most persistent and accurate obser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Tucanae
Delta Tucanae (δ Tuc, δ Tucanae) is a common proper motion pair located in the southwestern corner of the southern constellation of Tucana. Based upon an annual parallax shift of 13.00 mas as seen from Earth, is approximately 250 light years from the Sun. It is visible to the naked eye with a combined apparent visual magnitude of +4.48. As of 2013, the two components had an angular separation of 7.0 arc seconds along a position angle of 282°. The brighter primary, component A, is blue-white hued star a visual magnitude of 4.52. It is a B-type main-sequence star with a stellar classification of B9 Vn, where the 'n' suffix indicates "nebulous" absorption lines due to the star's rotation. It is spinning rapidly with a projected rotational velocity of 224 km/s, which is giving the star an oblate shape with an equatorial bulge that is an estimated 12% larger than the polar radius. The star has about three times the mass of the Sun and is around 232 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Tucanae
Eta Tucanae, Latinized from η Tucanae, is a probable binary star system in the southern constellation of Tucana, a few degrees to the north of Epsilon Tucanae. It is visible to the naked eye as a dim, white-hued point of light with an apparent visual magnitude of +5.00. parallax measurements provide a distance estimate of about 154 light years from the Sun, and it is drifting further away with a mean radial velocity of +32.5 km/s. It is a member of the 30 million year old Tucana-Horologium association of co-moving stars. The radial velocity for Eta Tucanae displays strong oscillations, suggesting this is a spectroscopic binary system. A companion was directly detected in 2014, but this result has some unexplained anomalies. The primary component is an A-type main-sequence star with a stellar classification of A1V. It is spinning rapidly with a projected rotational velocity of 190 km/s, giving it an equatorial bulge that is 15% larger than the polar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon Tucanae
Epsilon Tucanae (ε Tuc, ε Tucanae) is a solitary star in the southern constellation of Tucana. With an apparent visual magnitude of +4.50, it is faintly visible to the naked eye. Based upon an annual parallax shift of 8.74 mas as seen from Earth, it is located around 373 light years from the Sun. Levenhagen and Leister (2008) classified this star as B8 V, indicating a blue-white hued B-type main sequence star. However, Hiltner, Garrison, and Schild (1969) listed it with a classification of B9 IV, suggesting it may be a more evolved subgiant star. It is a rapidly rotating Be star that is an estimated 78% of the way through its main sequence lifetime. The projected rotational velocity is 300 km/s, which is giving it an oblate shape with an equatorial bulge that is an estimated 36% larger than the polar radius. It has a weak magnetic field with a strength of . It is the last star in the Hipparcos catalogue, HIP 118322, from the Hipparcos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Tucanae
Zeta Tucanae, Latinized from ζ Tucanae, is a star in the constellation Tucana. It is a spectral class F9.5 main sequence star with an apparent magnitude of +4.23. Despite having a slightly lower mass, this star is more luminous than the Sun. Based upon parallax measurements by the Hipparcos spacecraft, it is approximately 28.0 light years from Earth. This is one of the least variable stars observed during the Hipparcos mission. The composition and mass of this star are very similar to the Sun, with a slightly lower mass and an estimated age of three billion years. The solar-like qualities make it a target of interest for investigating the possible existence of a life-bearing planet. Based upon an excess emission of infrared radiation at 70 micrometres, this system is believed to have a debris disk. The disk is orbiting the star at a minimum radius of 2.3 astronomical units. It is radiating with a maximum temperature of 218 K. As of 2009, no planet has been discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rho Tucanae
Rho Tucanae (ρ Tuc, ρ Tucanae) is a binary star system in the southern constellation of Tucana. It is visible to the naked eye with a combined apparent visual magnitude of +5.38. Based upon an annual parallax shift of 24.37 mas as seen from Earth, it is located 131 light years from the Sun. This is a single-lined spectroscopic binary with a close, nearly circular orbit having a period of 4.82 days and an eccentricity of 0.02. The primary member, component A, is a yellow-white hued F-type main sequence star with a stellar classification of F6 V. It is around 2.6 billion years old and a member of the thin disk population. The primary has about 1.66 times the mass of the Sun 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 ... while the secondary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Tucanae
Beta Tucanae, Latinized from β Tucanae, is a group of six stars which appear to be at least loosely bound into a system in the constellation Tucana. Three of the stars are luminous and distinct enough to have been given their own Bayer designations, β¹ Tucanae through β³ Tucanae. The system is approximately 140 light years from Earth. β¹,² Tucanae The two brightest stars, Beta-1 Tucanae and Beta-2 Tucanae, also referred to as Beta Tucanae A and Beta Tucanae C, are 27 arcseconds, or at least 1100 astronomical units (AU) apart. They are both main sequence dwarfs, Beta-1 a blue-white B-type star with an apparent magnitude of +4.36, and Beta-2 a white A-type star with an apparent magnitude of +4.53. Both of these bright stars have at least one closer main sequence companion. Beta Tucanae B is a magnitude +13.5 M3-type star which is a close companion to Beta-1, being 2.4 arcseconds, or at least 100 AU away. Beta-2's companion, the 6th magnitude Beta Tucanae D, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Tucanae
Gamma Tucanae, Latinized from γ Tucanae, is a star in the constellation Tucana, marking the toucan's beak. It is faintly visible to the naked eye with an apparent visual magnitude of +3.99. Based upon an annual parallax shift of 43.37 mas as seen from Earth, this star is located about 75 light years from the Sun. It is moving away from the Sun with a radial velocity of +18 km/s. There is disagreement in the literature as to the stellar classification of this star. Malaroda (1975) has it catalogued as F1 III, which would suggest it is an evolved F-type giant star. Houk (1979) listed it as F3 IV/V, which appears to indicate a less evolved F-type star transitioning between the main sequence and subgiant star. Gray et al. (2006) has it classed as F4 V, which would match an ordinary F-type main-sequence star. This star is a suspected astrometric binary. The visible component has 1.55 times the mass of the Sun and 2.2 times the Sun's rad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three Enclosures
Traditional Chinese astronomy has a system of dividing the celestial sphere into asterisms or constellations, known as "officials" (Chinese ''xīng guān''). The Chinese asterisms are generally smaller than the constellations of Hellenistic tradition. The Song dynasty (13th-century) Suzhou planisphere shows a total of 283 asterisms, comprising a total of 1,565 individual stars. The asterisms are divided into four groups, the Twenty-Eight Mansions (, ''Èrshíbā Xiù'') along the ecliptic, and the Three Enclosures of the northern sky. The southern sky was added as a fifth group in the late Ming Dynasty based on European star charts, comprising an additional 23 asterisms. The Three Enclosures (, ''Sān Yuán'') include the Purple Forbidden Enclosure, which is centered on the north celestial pole and includes those stars which could be seen year-round,Needham, J.Astronomy in Ancient and Medieval China. ''Philosophical Transactions of the Royal Society of London''. Series A, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Tucanae
Alpha Tucanae (α Tuc, α Tucanae) is a binary star system in the southern circumpolar constellation of Tucana. With an apparent visual magnitude of 2.86, it can be seen with the naked eye from the southern hemisphere. Using parallax measurements, the distance to this system can be estimated as . A cool star with a surface temperature of 4300 K, it is 424 times as luminous as the sun and 37 times its diameter. It is 2.5 to 3 times as massive. It is unclear what stage of evolution the star is in. This is a spectroscopic binary, which means that the two stars have not been individually resolved using a telescope, but the presence of the companion has been inferred from measuring changes in the spectrum of the primary. The orbital period of the binary system is 4197.7 days (11.5 years). The primary component has a stellar classification of K3 III, which indicates it is a giant star that has exhausted the supply of hydrogen at its core and evolved away from the main ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
