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List Of Stars In Ara ...
This is the list of notable stars in the constellation Ara, sorted by decreasing brightness. ; Notes See also *List of stars by constellation References * * * * * * * Wagman, M., (2003). ''Lost Stars'', The McDonald & Woodward Publishing Co., Blackburg, Virginia. {{DEFAULTSORT:stars in Ara, List of *List Ara ARA may refer to: Media and the arts * American-Romanian Academy of Arts and Sciences * '' Artistička Radna Akcija'', compilation album released in former Yugoslavia * Associate of the Royal Academy, denoting membership in the British Royal Aca ... [...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] |
Lambda Eridani Variable
A Lambda Eridani Variable is a class of Be stars that show small amplitude variations of a few hundredths of a magnitude. The variations are highly regular with periods between 0.5 and 2.0 days, and they were initially described as periodic Be stars. Lambda Eridani is an example and the prototype. This has been ascribed to non-radial pulsations, inhomogeneous rotating discs, or the rotation of the star itself. These stars are rarely classified, or are classified incorrectly. The General Catalogue of Variable Stars does not have a type for λ Eridani variables, only GCAS for Gamma Cassiopeiae variables and BE for non-GCAS Be star variables. λ Eridani itself is incorrectly listed as a Beta Cephei variable. The AAVSO The American Association of Variable Star Observers (AAVSO) is an international nonprofit organization, founded in 1911, focused on coordinating, analyzing, publishing, and archiving variable star observations made largely by amateur astronomers. ... Internationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extrasolar Planet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. There are many methods of detecting exoplanets. Transit (astronomy), Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, List of multiplanetary systems, multiple planets have been observed around a star. About 1 in 5 Solar analog, Sun-like starsFor the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars was not available so this statistic is an extrapolation from data about K-type star, K-type stars. have an "Earth-sized"For the purpose of this 1 in 5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mu Arae
Mu Arae (μ Arae, abbreviated Mu Ara, μ Ara), often designated HD 160691, officially named Cervantes , is a main sequence G V star, G-type star approximately 50 light-years away from the Sun in the constellation of Ara (constellation), Ara. The star has a planetary system with four known Exoplanet, extrasolar planets (designated Mu Arae b, Mu Arae c, c, Mu Arae d, d and Mu Arae e, e; later named Quijote, Dulcinea, Rocinante and Sancho, respectively), three of them with masses comparable with that of Jupiter. Mu Arae c, the innermost, was the first hot Neptune or super-Earth discovered. Nomenclature ''μ Arae'' (Latinisation of names, Latinised to ''Mu Arae'') is the star's Bayer designation. HD 160691 is the entry in the Henry Draper Catalogue. The established convention for extrasolar planets is that the planets receive designations consisting of the star's name followed by lower-case Latin alphabet, Roman letters starting from "b", in order of discovery. This system ... [...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] |
Lambda Arae
Lambda Arae (λ Ara, λ Arae) is the Bayer designation for a star in the southern constellation of Ara. It is at a distance of from Earth. The apparent visual magnitude of this star is 4.77, making it bright enough to be seen with the naked eye. The spectrum of this star matches a stellar classification of F4 V, which places it among the category of F-type main sequence stars. It shines with 4.7 times the luminosity of the Sun. The outer atmosphere is radiating this energy at an effective temperature of 6,495 K, giving it the yellow-white hue of an F-type star. There is some evidence that this may be a binary star system consisting of two stars with identical masses. Examination of Lambda Arae with the Spitzer Space Telescope shows an excess of infrared emission at a wavelength of 70 μm. This suggests it may be orbited by a disk of dust at a radius of more than 15 astronomical unit The astronomical unit (symbol: au, or or AU) is a unit of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigma Arae
Sigma Arae (σ Ara, σ Arae) is the Bayer designation for a star in the southern constellation of Ara. It is visible to the naked eye with an apparent visual magnitude of +4.575. The distance to this star, based upon an annual parallax shift of 8.62 mas, is around . This is an A-type main sequence star with a stellar classification of A0 V. Unusually for an A-type star, X-ray emissions with a luminosity of have been detected from Sigma Arae. Normally this is explained by the presence of a lower mass orbiting companion star. However, such a scenario does not appear to hold true for this star. Instead, the signature of a surface magnetic field A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ... has been detected with a strength of roughly , indicating the source of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon1 Arae
Epsilon1 Arae (ε1 Ara, ε1 Arae) is the Bayer designation for a star in the constellation Ara, the Altar. It is visible to the naked eye with an apparent visual magnitude of +4.1 Based upon an annual parallax shift of 9.04 mas, this star is around distant from the Earth. ε1 Arae is an evolved giant star with a stellar classification of K3 III. It is around 74% more massive than the Sun. At an age of about 1.7 billion years, the outer envelope of the star has expanded to almost 34 times the Sun's radius. It is radiating energy into space at an effective temperature of 4,176 K, giving it the orange-hued glow of a K-type star. ε1 Arae was known as (spelled as "Guī yī", meaning: "the 1st (star) of '") in traditional Chinese astronomy. Chevalier, S., and Tsuchihashi, P., (1911): "Catalogue d'Étoiles fixes, observés a Pekin sous l' Empereur Kien Long (Qianlong (Chien-Lung)), XVIIIe siecle", ''Annales de l'Observatoire Astronomique de Zô-Sé''. ... [...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] |
Eta Arae
Eta Arae, Latinized from η Arae, is the Bayer designation for a single star in the southern constellation of Ara. It is approximately from Earth and is visible to the naked eye with an apparent visual magnitude of 3.76. The star is moving away from the Sun with a radial velocity of +9 km/s. The spectrum of this star matches a stellar classification of K5 III, indicating that, at an estimated age of five billion years, it has reached the giant star stage of its evolution. With 1.12 times the mass of the Sun, it has an outer envelope that has expanded to 40 times the Sun's radius. The star is now spinning so slowly that it takes more than eleven years to complete a single rotation. Eta Arae is radiating energy into space from its photosphere with 575 times the Sun's luminosity at an effective temperature of 4,147 K, giving it the orange-hued glow of a K-type star. It has a magnitude 13.5 optical companion, located 23.4 arcseconds away along a positi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theta Arae
Theta Arae, Latinized from θ Arae, is the Bayer designation for a star in the constellation Ara. It has an apparent visual magnitude of +3.67, which is bright enough to be seen with the naked eye. Based upon an annual parallax shift of 4.01 mas, Theta Arae is distant from the Earth. This is a supergiant star with a stellar classification of B2 Ib. It has nearly nine times the mass of the Sun and is over 20 times the Sun's radius. The outer atmosphere of this star has an effective temperature of 17,231 K; much hotter than the surface of the Sun. At this heat, the star shines with the characteristic blue-white hue of a B-type star A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type stars .... References External links SimbadImage Theta Arae {{DEFAULTSORT:Theta Ara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Arae
Delta Arae, Latinized from δ Arae, is the Bayer designation for a double star in the southern constellation Ara. It has an apparent visual magnitude of 3.62 and is visible to the naked eye. Based upon an annual parallax of 16.48 mas, it is about distant from the Earth. Delta Arae is massive B-type main sequence star with a stellar classification of B8 Vn. The 'n' suffix indicates the absorption lines are spread out broadly because the star is spinning rapidly. It has a projected rotational velocity of 255 km/s, resulting in an equatorial bulge with a radius 13% larger than the polar radius. It has a magnitude 9.5 companion G-type main sequence star that may form a binary star system with Delta Arae. There is a 12th magnitude optical companion located 47.4 arcseconds away along a position angle of 313°. Etymology Delta Arae was known as (meaning: "the 3rd (star) of '") in traditional Chinese astronomy. Chevalier, S., and Tsuchihashi, P., (1911): "Cata ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
