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List Of Stars In Tucana ...
This is the list of notable stars in the constellation Tucana, sorted by decreasing brightness. See also *List of stars by constellation Notes References * * * * * * Allen, R. H. (1963). ''Star Names; Their Lore and Meaning'', Dover Publications, Inc., New York, p. 418. * Wagman, M. (2003). ''Lost Stars'', The Mcdonald & Woodward Publishing Company, Blacksburg, pp. 306–307. {{Stars of Tucana *List 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 D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sky, night, but their immense distances from Earth make them appear as fixed stars, fixed points of light. The most prominent stars have been categorised into constellations and asterism (astronomy), asterisms, and many of the brightest stars have proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. The observable universe contains an estimated to stars. Only about 4,000 of these stars are visible to the naked eye, all within the Milky Way galaxy. A star's life star formation, begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Its stellar ... [...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] |
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] |
Iota Tucanae
Iota Tucanae (ι Tuc, ι Tucanae) is a solitary star in the southern constellation of Tucana. Based upon an annual parallax shift of 10.72 mas as seen from Earth, it is located around 304 light years from the Sun. With an apparent visual magnitude of +5.33, it is faintly visible to the naked eye. This is a yellow-hued G-type giant star with a stellar classification of G5 III. It is classified as a semiregular variable star, showing a periodicity of 66.8 days with an amplitude of 0.0202 in visual magnitude. Iota Tucanae is an X-ray source with a luminosity of . It has an estimated 2.2 times the mass of the Sun, and, at the age of 1.69 billion years, it has evolved away from the main sequence, expanding to 11 times the Sun's radius. The star radiates 65 times the solar luminosity from its 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 sam ... [...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] |
Semiregular Variable
In astronomy, a semiregular variable star, a type of variable star, is a giant or supergiant of intermediate and late (cooler) spectral type showing considerable periodicity in its light changes, accompanied or sometimes interrupted by various irregularities. Periods lie in the range from 20 to more than 2000 days, while the shapes of the light curves may be rather different and variable with each cycle. The amplitudes may be from several hundredths to several magnitudes (usually 1-2 magnitudes in the V filter). Classification The semiregular variable stars have been sub-divided into four categories for many decades, with a fifth related group defined more recently. The original definitions of the four main groups were formalised in 1958 at the tenth general assembly of the International Astronomical Union (IAU). The General Catalogue of Variable Stars (GCVS) has updated the definitions with some additional information and provided newer reference stars where old examples such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nu Tucanae
ν Tucanae, Latinized as Nu Tucanae, is a solitary, variable star in the southern constellation of Tucana. This red-hued object is visible to the naked eye as a faint star with an apparent visual magnitude that fluctuates around +4.80. It is located approximately 290 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −3 km/s. This object is an aging red giant with a stellar classification of M4 III, currently on the asymptotic giant branch. With the supply of hydrogen exhausted at its core, the star has cooled and expanded off the main sequence; at present it has 49 times the Sun's radius. It is classified as a slow irregular variable and its brightness varies from magnitude +4.75 to +4.93. Cyclical periods of 22.3, 24.4, 24.8, 25.1, 25.5, 33.8, 50.6, 80.1, 123.2, and 261.8 days have been reported for its variations. On average, the star is radiating around 400 times the luminosity of the Sun from its photo ... [...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] |
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] |
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] |
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] |
