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EU Delphini
This is the list of notable stars in the constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ... Delphinus, sorted by decreasing brightness. See also * List of stars by constellation References * * * * * * * * {{Stars of Delphinus *List Delphinus ... [...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] |
Spectroscopic Binary
A binary star is a system of two star, stars that are gravity, gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in which case they are called ''visual binaries''. Many visual binaries have long orbital periods of several centuries or millennia and therefore have orbits which are uncertain or poorly known. They may also be detected by indirect techniques, such as spectroscopy (''spectroscopic binaries'') or astrometry (''astrometric binaries''). If a binary star happens to orbit in a plane along our line of sight, its components will eclipse and transit (astronomy), transit each other; these pairs are called ''eclipsing binaries'', or, together with other binaries that change brightness as they orbit, ''photometric binaries''. If components in binary star systems are close enough they can gravitationally distort their mutual outer stella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iota Delphini
Iota Delphini (ι Del, ι Delphini) is a star in the constellation Delphinus. It has an apparent magnitude of about 5.4, meaning that it is just barely visible to the naked eye. Based upon parallax measurements made by the Gaia spacecraft, this star is located at a distance of 196 light years. Iota Delphini's spectral type is A1IV, meaning it is an A-type subgiant. Observations of the star's spectrum reveal a periodic Doppler shift. This means that Iota Delphini is a spectroscopic binary with a period of 11 days and an eccentricity of 0.23. However, almost no information is known about the companion star. Iota Delphini appears to be an Am star, also known as a metallic-line star. These types of stars have spectra indicating varying amounts of metals, like iron.Am star , ''The Internet Encyclopedia of Science'', David Darling. Acces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Delphini
Eta Delphini, Latinized from η Delphini, is a candidate astrometric binary star system in the northern constellation of Delphinus. It has an apparent magnitude of about 5.4, meaning that it is faintly visible to the naked eye. Based upon a parallax measurement of 13.81 mas made by the Hipparcos spacecraft, this star is around 240 light years away from the Sun. It is advancing in general direction of the Earth with a radial velocity of −25 km/s. The stellar classification of the visible component is A3 IVs, which matches an A-type subgiant star with narrow absorption lines. It is a suspected chemically peculiar star that is about of the way through its main sequence lifetime. SIMBAD lists this star as a variable star, although it is not catalogued as such in the GCVS. It has more than double the mass and radius of the Sun, and is radiating 35 times the Sun's luminosity from its photosphere at an effective temperature The effective temperature of a body ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
17 Delphini
17 Delphini is a solitary star in the equatorial constellation Delphinus. It has an absolute magnitude of −0.64 and apparent magnitude of 5.18, allowing it to be faintly seen with the naked eye. Located 517 light years away, it is approaching the Solar System with a heliocentric radial velocity of . 17 Delphini is an orange giant that is most likely on the horizontal branch (84% probability). At present it has 2.33 times the mass of the Sun, but at an age of 832 million years — has expanded to 23.36 times the radius of the Sun. It shines at from its enlarged photosphere at an effective temperature of 4,616 K, giving it an orange glow. 17 Del has an iron abundance 64% that of the Sun and spins modestly with a projected rotational velocity of . 17 Del is suspected to be a 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kappa Delphini
κ Delphini (Latinised as Kappa Delphini, abbreviated to κ Del or kappa Del) is a binary star system in the constellation Delphinus. It is faintly visible to the naked eye, with an apparent magnitude of 5.05. It is located about 98.8 light-years away, based on its parallax. Kappa Delphini is an astrometric binary. The primary star is an early G-type subgiant star. It has a mass 1.61 times that of the Sun, and is 6.8 times more luminous. The companion star regularly perturbs the G-type primary star primary, causing it to wobble around the barycenter. From this, an orbital period of 45 years has been calculated. The secondary star is a low-mass star, at only . A third star is 12th magnitude ADS 14101 B, away in 2001, but it is a background object. HD 196794 is an 8th magnitude K2 subgiant A subgiant is a star that is brighter than a normal main-sequence star of the same spectral class, but not as bright as giant stars. The term subgiant is applied both to a particu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rho Aquilae
Rho Aquilae, ρ Aquilae, is the Bayer designation for a star in the northern constellation of Delphinus. It has an apparent visual magnitude of 4.94 and is bright enough to be seen with the naked eye in good conditions. Distance, proper motion and constellation The annual parallax shift is 21.75 milliarcseconds, which corresponds to a distance of the star of around from Earth. Relatively high proper motion resulted in the star crossing the border from Aquila into Delphinus in 1992. Rho Aquilae is therefore a rare occurrence of a mismatch between current constellation and Bayer designation constellation. The star is in the low-northern constellation of Delphinus therefore at least seasonally visible to all but the high southern latitudes. Chinese constellations and components This star has the traditional name ''Tso Ke'', from the Cantonese 左旗 ''jo keih'' meaning "the left flag". In Chinese, ( in Mandarin), within the Ox, refers to an asterism consisting of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Delphini
Zeta Delphini (ζ Delphini) is a star in the constellation of Delphinus. With an apparent magnitude of about 4.6, it is faintly visible to the naked eye. Parallax measurements of the system made by the Hipparcos spacecraft put it at a distance of about 220 light-years, or 67 parsecs. Zeta Delphini has a spectral type of A3V, implying it is an A-type main-sequence star. These types of stars are bluish-white colored, and have effective temperatures between 7100 and 11500 K: Zeta Delphini has a temperature of 8336 K. Its age is estimated to be around 500 million years, considerably younger than the Sun. In 2014, the discovery of a brown dwarf around Zeta Delphini was announced. Zeta Delphini B is a brown dwarf with a spectral type of L5 (but may be from L3 to L7), and has a mass of about 55 Jupiters. At over 13 arcsecond A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Scuti Variable
A Delta Scuti variable (sometimes termed dwarf cepheid when the V-band amplitude is larger than 0.3 mag.) is a subclass of young pulsating star. These variables as well as classical cepheids are important standard candles and have been used to establish the distance to the Large Magellanic Cloud, globular clusters, open clusters, and the Galactic Center. The variables follow a period-luminosity relation in certain passbands like other standard candles such as Cepheids. SX Phoenicis variables are generally considered to be a subclass of Delta Scuti variables that contain old stars, and can be found in globular clusters. SX Phe variables also follow a period-luminosity relation. One last sub-class are the pre-main sequence (PMS) Delta Scuti variables. The OGLE and MACHO surveys have detected nearly 3000 Delta Scuti variables in the Large Magellanic Cloud. Typical brightness fluctuations are from 0.003 to 0.9 magnitudes in V over a period of a few hours, although the amplitude ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Delphini
Delta Delphini, Latinized from δ Delphini, is a binary star in the northern constellation of Delphinus. It is visible to the naked eye with an apparent visual magnitude of 4.43. Based upon an annual parallax shift of 14.61 mas as seen from the Earth, the system is located about 223 light years from the Sun. This is a double-lined spectroscopic binary system with an orbital period of 40.58 days. The two components are nearly identical chemically peculiar stars, having a combined stellar classification of kA7hF1VmF1pSrEuCr:. This notation indicates the calcium K line matches an A7 star, the hydrogen lines an F1 star, and the metal lines An Am star or metallic-line star is a type of chemically peculiar star of spectral type A whose spectrum has strong and often variable absorption lines of metals such as zinc, strontium, zirconium, and barium, and deficiencies of others, such as ... an F1 star, with particularly strong lines of strontium, europium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Delphini
Gamma Delphini, which is Latinized from γ Delphini, is a wide binary star system in the northern constellation of Delphinus. The star marks one corner of the asterism " Job's Coffin". The pair can be split with a modest amateur telescope and have been described as "one of the prettier pairs in the sky", with their contrasting colors said to be orange and lime in appearance. Together, the system is visible to the naked eye with a combined apparent visual magnitude of 3.87. Space motion The system is located at a distance of 115 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −7 km/s. It is a member of the thin disk population, and is a proposed member of the Wolf 630 moving group. This star was found to be a double by Christian Mayer and later observed by William Herschel on Sept 27th, 1779. It was later included as STF 2727 in the catalogue compiled by F. G. W. Struve and can be found under this name in the Wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon Delphini
Epsilon Delphini (ε Delphini, abbreviated Eps Del, ε Del), officially named Aldulfin , is a solitary, blue-white hued star in the northern constellation of Delphinus. It is visible to the naked eye with an apparent visual magnitude of 4.03. Based upon an annual parallax shift of 9.87 mas as seen from the Earth, the system is located about 330 light-years from the Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi .... At Epsilon Delphini's distance, the apparent magnitude, visual magnitude is diminished by an extinction (astronomy), extinction factor of 0.11 due to Cosmic dust, interstellar dust. The star is moving closer to the Sun with a radial velocity of −19 km/s. This is a Stellar classification#Class B, B-type giant star with a stellar classificatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
