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Delta-1 Tauri
Delta¹ Tauri (δ¹ Tauri, abbreviated Delta¹ Tau, δ¹ Tau) is a double star in the zodiac constellation of Taurus. Based upon an annual parallax shift of 20.96 mas as seen from Earth, it is located roughly 156 light-years distant from the Sun. The system is faintly visible to the naked eye with a combined apparent visual magnitude of +3.772. It is considered a member of the Hyades cluster. The two constituents are designated δ¹ Tauri A and B. A is itself a binary star with components designated δ¹ Tauri Aa (officially named Secunda Hyadum , the traditional name for the entire system) and Ab. Nomenclature ''δ¹ Tauri'' ( Latinised to ''Delta¹ Tauri'') is the system's Bayer designation. The designations of the two constituents as ''Delta¹ Tauri A'' and ''B'', and those of ''A's'' components - ''Delta¹ Tauri Aa'' and ''Ab'' - derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IAU Working Group On Star Names
The International Astronomical Union (IAU) established a Working Group on Star Names (WGSN) in May 2016 to catalog and standardize proper names for stars for the international astronomical community. It operates under Division C – Education, Outreach and Heritage. The IAU states that it is keen to make a distinction between the terms ''name'' and ''designation''. To the IAU, ''name'' refers to the (usually colloquial) term used for a star in everyday conversation, while ''designation'' is solely alphanumerical, and used almost exclusively in official catalogues and for professional astronomy. (The WGSN notes that transliterated Bayer designations (e.g., Tau Ceti) are considered a special historical case and are treated as designations.) Terms of reference The terms of reference for the WGSN for the period 2016–2018 were approved by the IAU Executive Committee at its meeting on 6 May 2016. In summary, these are to: * establish IAU guidelines for the proposal and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Period
The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets, exoplanets orbiting other stars, or binary stars. For celestial objects in general, the sidereal period ( sidereal year) is referred to by the orbital period, determined by a 360° revolution of one body around its primary, e.g. Earth around the Sun, relative to the fixed stars projected in the sky. Orbital periods can be defined in several ways. The tropical period is more particularly about the position of the parent star. It is the basis for the solar year, and respectively the calendar year. The synodic period incorporates not only the orbital relation to the parent star, but also to other celestial objects, making it not a mere different approach to the orbit of an object around its parent, but a period of orbital relations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Star
A binary star is a system of two stars that are 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 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 stellar atmospheres. In some cases, thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Star Names
Chinese star names (Chinese: , ''xīng míng'') are named according to ancient Chinese astronomy and astrology. The sky is divided into star mansions (, ''xīng xiù'', also translated as "lodges") and asterisms (, ''xīng guān''). The system of 283 asterisms under Three Enclosures and Twenty-eight Mansions was established by Chen Zhuo of the Three Kingdoms period, who synthesized ancient constellations and the asterisms created by early astronomers Shi Shen, Gan De and Wuxian. Since the Han and Jin Dynasties, stars have been given reference numbers within their asterisms in a system similar to the Bayer or Flamsteed designations, so that individual stars can be identified. For example, Deneb (α Cyg) is referred to as (''Tiān Jīn Sì'', the Fourth Star of Celestial Ford). In the Qing Dynasty, Chinese knowledge of the sky was improved by the arrival of European star charts. ''Yixiang Kaocheng'', compiled in mid-18th century by then deputy Minister of Rites Ignaz Kögler, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambda Tauri
Lambda Tauri (λ Tau, λ Tauri) is a triple star system in the constellation Taurus. In the ''Calendarium of Al Achsasi Al Mouakket'', this star was designated ''Sadr al Tauri'', which was translated into Latin as ''Pectus Tauri'', meaning "the bull chest". In 1848, the light from this system was found to vary periodically and it was determined to be an eclipsing binary system—the third such discovered. The components of this system have a combined apparent visual magnitude of +3.37 at its brightest, making it one of the List of stars in Taurus, brighter members of the constellation. Based upon parallax measurements from the Hipparcos mission, the distance to this system is approximately . System The inner pair of this triple star system, Lambda Tauri AB, orbit around each other with a orbital period, period of 3.95 days and a low orbital eccentricity, eccentricity of about 0.025. Their Orbital plane (astronomy), orbital plane is inclined by around 76° to the li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
71 Tauri
71 Tauri is a suspected triple star system in the zodiac constellation Taurus, located 146 light years from the Sun. It is visible to the naked eye as a faint, yellow-white hued star with an apparent visual magnitude of +4.48. The star is moving further away from the Earth with a heliocentric radial velocity of +38 km/s. It is a member of the Hyades open cluster. The primary component is an F-type main-sequence star with a stellar classification of F0 V. It is a Delta Scuti variable with an amplitude of 0.02 in magnitude and a frequency of 0.16 d−1. This star has about 1.94 times the mass of the Sun and 3.34 times the Sun's radius. It has a projected rotational velocity of 192 km s−1, for an estimated rotation period of 14.2 days. Extreme ultraviolet flares have been observed coming from this star's hot corona Corona (from the Latin for 'crown') most commonly refers to: * Stellar corona, the outer atmosphere of the Sun or another star * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldebaran
Aldebaran (Arabic: “The Follower”, "الدبران") is the brightest star in the zodiac constellation of Taurus. It has the Bayer designation α Tauri, which is Latinized to Alpha Tauri and abbreviated Alpha Tau or α Tau. Aldebaran varies in brightness from an apparent visual magnitude 0.75 down to 0.95, making it (typically) the fourteenth-brightest star in the night sky. It is located at a distance of approximately 65 light-years from the Sun. The star lies along the line of sight to the nearby Hyades cluster. Aldebaran is a giant star that is cooler than the Sun with a surface temperature of , but its radius is about 44 times the Sun's, so it is over 400 times as luminous. It spins slowly and takes 520 days to complete a rotation. Aldebaran is believed to host a planet several times the mass of Jupiter, named . The planetary exploration probe Pioneer 10 is heading in the general direction of the star and should make its closest approach in about two million ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Tauri
Gamma Tauri (γ Tauri, abbreviated Gamma Tau, γ Tau) is either a solitary, binary star, binary or double star (the Washington Double Star Catalog notes it as a "Dubious Double" or "Bogus Binary") that marks the tip of the "V" in the constellation of Taurus (constellation), Taurus. It is a member of, and located within about 2.5 parsecs of the center of, the Hyades (star cluster), Hyades star cluster, the nearest open cluster to the Sun. Based upon parallax measurements, Gamma Tauri is approximately 154 light-years from the Sun. Considered as a pair of stars, the two components are designated Gamma Tauri A (officially named Prima Hyadum , the traditional name for the system) and B. Nomenclature ''γ Tauri'' (Latinisation of names, Latinised to ''Gamma Tauri'') is the system's Bayer designation. The designations of the two potential components as ''Gamma Tauri A'' and ''B'' derive from the convention used by the Washington Multiplicity Catalog (WMC) for Star system, mult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta3 Tauri
Delta3 Tauri (δ3 Tauri) is a binary star system in the zodiac constellation of Taurus. Based upon an annual parallax shift of 21.96 mas as seen from Earth, it is located roughly 149 light years distant from the Sun. It is visible to the naked eye with a combined apparent visual magnitude of +4.32. δ3 Tauri is separated from δ1 Tauri by 0.72° on the sky. This star also has the traditional Latin name Cleeia, from the Greek Kleeia (transliteration of Κλεεια), who was one of the Hyades sisters. It is considered a member of the Hyades cluster. In Chinese, (), meaning ''Net'', refers to an asterism consisting δ3 Tauri, ε Tauri, δ1 Tauri, γ Tauri, Aldebaran, 71 Tauri and λ Tauri. Consequently, the Chinese name for δ3 Tauri itself is (), "the Second Star of Net". [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon Tauri
Epsilon Tauri or ε Tauri, formally named Ain (), is an orange giant star located approximately 45 parsecs (147 light-years) from the Sun in the constellation of Taurus. An extrasolar planet (designated Epsilon Tauri b, later named Amateru) is believed to be orbiting the star. It is a member of the Hyades open cluster. As such its age is well constrained at 625 million years. It is claimed to be the heaviest among planet-harboring stars with reliable initial masses although the star HD 13189 is potentially more massive. Given its large mass, this star, though presently of spectral type K0 III, was formerly of spectral type A that has now evolved off the main sequence into the giant phase. It is regarded as a red clump giant; that is, a core-helium burning star. Since Epsilon Tauri lies near the plane of the ecliptic, it is sometimes occulted by the Moon and (very rarely) by planets. It has an 11th magnitude companion 182 arcseconds from the primary. Nomenclature ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterism (astronomy)
An asterism is an observed pattern or group of stars in the sky. Asterisms can be any identified pattern or group of stars, and therefore are a more general concept than the formally defined 88 constellations. Constellations are based on asterisms, but unlike asterisms, constellations outline and today completely divide the sky and all its celestial objects into regions around their central asterisms. For example, the asterism known as the Big Dipper comprises the seven brightest stars in the constellation Ursa Major. Another is the asterism of the Southern Cross, within the constellation of Crux. Asterisms range from simple shapes of just a few stars to more complex collections of many stars covering large portions of the sky. The stars themselves may be bright naked-eye objects or fainter, even telescopic, but they are generally all of a similar brightness to each other. The larger brighter asterisms are useful for people who are familiarizing themselves with the night sky. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
