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List Of Stars In Grus
This is the list of notable stars in the constellation Grus, sorted by decreasing brightness. See also *List of stars by constellation All stars but one can be associated with an IAU constellation. IAU constellations are areas of the sky. Although there are only 88 IAU constellations, the sky is actually divided into 89 irregularly shaped boxes as the constellation Serpens is spl ... References * * * * * * {{Stars of Grus *List Grus ... [...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] |
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 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mu2 Gruis
Mu2 Gruis, Latinized from μ2 Gruis, is a yellow-hued star or star system in the southern constellation of Grus. It is a suspected astrometric binary, showing a variation in proper motion due to gravitational acceleration. Mu2 Gruis is visible to the naked eye with an apparent visual magnitude of 5.10. The distance to this system, as determined using an annual parallax shift of 13.2 mas as seen from the Earth, is around 248 light years. It is drifting further away with a heliocentric radial velocity of +12.5 km/s. The primary component is an evolved giant star with a stellar classification of G8 III. It is a periodic variable star, showing a change in brightness with an amplitude of 0.004 magnitude at the rate of 7.50983 times per day. With the supply of hydrogen at its core exhausted, the star has cooled and expanded until now it has 10 times the radius of the Sun. It is radiating 56 times the luminosity of the Sun The solar luminosity () ... [...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, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Gruis
Eta Gruis, Latinized from η Gruis, is a solitary star in the southern constellation of Grus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.85. Based upon an annual parallax shift of as seen from the Earth, the system is located about 460 light years from the Sun. The star is drifting further away with a radial velocity of +28 km/s. This object is an evolved K-type giant star with a stellar classification of , where the suffix notation indicates this is an intermediate CN star. It is a periodic microvariable with an amplitude of 0.0055 magnitude and a frequency of 0.36118 cycles per day. With the supply of hydrogen exhausted at its core, the star has expanded and cooled, now having 31 times the Sun's girth. It is radiating 338.5 times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,420 K. Eta Gruis has a magnitude 11.5 visual companion located at an angu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rho Gruis
Rho Gruis, a Latinization of ρ Gruis, is a solitary star in the southern constellation of Grus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.85. Based upon an annual parallax shift of 14.16 mas as seen from the Earth, the system is located about 230 light years from the Sun. It is drifting further away with a radial velocity of 31 km/s. This object is an evolved K-type giant star with a stellar classification of K0 III. It has exhausted the supply of hydrogen at its core, causing it to cool and expand. At present it has 12 times the radius of the Sun. With 1.9 times the mass of the Sun it is a red clump star, which indicates it is on the horizontal branch generating energy through helium fusion at its core. It is radiating 67 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,737 K. Rho Gruis has two visual companions: a magnitude 14.0 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mu1 Gruis
Mu1 Gruis, Latinized from μ1 Gruis, is a binary star system in the southern constellation of Grus. It is visible to the naked eye with a combined apparent visual magnitude of 4.79. The distance to this system, as determined using an annual parallax shift of 11.44 mas as seen from the Earth, is around 275 light years. It is drifting closer with a heliocentric radial velocity of −5 km/s. The pair orbit each other with a period of 19 years and an eccentricity of 0.56. The yellow-hued primary component is an evolved giant star with stellar classification of G III and visual magnitude 5.20. With the supply of hydrogen at its core exhausted, it cooled and expanded; at present it has nine times the girth of the Sun. The star is radiating 67 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 5,422 K. The secondary component is magnitude 6.68 and classed as a G-type star, although its color index an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambda Gruis
Lambda Gruis, Latinized from λ Gruis, is a solitary, orange-hued star in the southern constellation of Grus. With an apparent visual magnitude of 4.47, it is visible to the naked eye as a faint point of light. The distance to this star, as determined using an annual parallax shift of 13.47 mas as seen from the Earth, is around 242 light years. It is drifting further away with a radial velocity of +39 km/s, having come to within some 805,000 years ago. This is an evolved K-type giant star with a stellar classification of K3 III, having exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. It has about 2.4 times the mass of the Sun and has expanded to 22.3 times the Sun's radius. The star is radiating 155 times the Sun's luminosity 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, galaxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theta Gruis
Theta Gruis, Latinized from θ Gruis, is a triple star system in the southern constellation of Grus. Its combined apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ... is 4.28, which is bright enough to be seen with the naked eye. The system contains a magnetic Delta Delphini-like F5 star with a close fainter companion, plus a more distant G2 main sequence star. References {{DEFAULTSORT:Theta Gruis Am stars F-type main-sequence stars G-type main-sequence stars Triple star systems Grus (constellation) Gruis, Theta 218227 114131 8787 Durchmusterung objects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta2 Gruis
Delta2 Gruis, Latinized from δ2 Gruis, is a solitary, red-hued star in the southern constellation of Grus. It is visible to the naked eye with an apparent visual magnitude of about 4. Based upon an annual parallax shift of 9.88 mas as seen from the Earth, the star is located around 330 light years from the Sun. It is moving further away from the Sun with a radial velocity of +3 km/s. This is an evolved red giant star with a stellar classification of M4.5 IIIa. It is a pulsating variable with multiple periods, including 20.6, 24.1, 24.5, and 32.3 days. The strongest period is 33.3 days with an amplitude of 0.043 magnitude. It has a magnitude 9.71 visual companion at an angular separation of 60.4 arc seconds along a position angle In astronomy, position angle (usually abbreviated PA) is the convention for measuring angles on the sky. The International Astronomical Union defines it as the angle measured relative to the north celestial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Gruis
Zeta Gruis, Latinised from ζ Gruis, is a solitary star in the southern constellation of Grus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.12. Based upon an annual parallax shift of 24.5 mas as seen from the Earth, the system is located about 133 light-years from the Sun. This is an evolved K-type giant star with a stellar classification of , where the suffix notation indicates underabundances of iron and cyanogen in the spectrum. Having exhausted the supply of hydrogen at its core, the star has expanded and cooled; at present it has 10 times the girth of the Sun. The star is radiating 46 times the 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 ... from its swollen photosphere at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta1 Gruis
Delta1 Gruis, Latinized from δ1 Gruis, is a candidate binary star system in the constellation Grus. With a peak apparent visual magnitude of 4.0 it is bright enough to be seen with the naked eye at night. The distance to this system, as determined using an annual parallax shift of 10.54 mas as seen from the Earth, is around 309 light years. It is gradually moving away from the Sun with a radial velocity of +4.9 km/s. The brighter component of this system is an evolved, yellow-hued, G-type giant star with a stellar classification of G6/8 III. It is a semiregular variable that ranges between apparent magnitudes 3.99 and 4.2, located 325 light-years from Earth. Delta1 Gruis has around 3 times the mass and 24 times the diameter of the Sun. The fainter companion is a magnitude 12.8 star at an angular separation of 5.6 arc seconds, as of 2008. See also *List of stars in Grus This is the list of notable stars in the constellation Grus, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
