[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/rho-orionis-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/en\/wiki24\/rho-orionis-wikipedia\/","headline":"Rho Orionis – Wikipedia","name":"Rho Orionis – Wikipedia","description":"From Wikipedia, the free encyclopedia Binary star system in the constellation Orion Rho Orionis, Latinised from \u03c1 Orionis, is the","datePublished":"2017-12-18","dateModified":"2017-12-18","author":{"@type":"Person","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/author\/lordneo\/#Person","name":"lordneo","url":"https:\/\/wiki.edu.vn\/en\/wiki24\/author\/lordneo\/","image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","height":96,"width":96}},"publisher":{"@type":"Organization","name":"Enzyklop\u00e4die","logo":{"@type":"ImageObject","@id":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","url":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","width":600,"height":60}},"image":{"@type":"ImageObject","@id":"https:\/\/wikimedia.org\/api\/rest_v1\/media\/math\/render\/svg\/765f6c355947a6295acbef58c006a026ecb6a266","url":"https:\/\/wikimedia.org\/api\/rest_v1\/media\/math\/render\/svg\/765f6c355947a6295acbef58c006a026ecb6a266","height":"","width":""},"url":"https:\/\/wiki.edu.vn\/en\/wiki24\/rho-orionis-wikipedia\/","wordCount":3268,"articleBody":"From Wikipedia, the free encyclopediaBinary star system in the constellation OrionRho Orionis, Latinised from \u03c1 Orionis, is the Bayer designation for an orange-hued binary star system in the equatorial constellation of Orion. It is visible to the naked eye with an apparent visual magnitude of +4.44.[2] The star shows an annual parallax shift of 9.32\u00a0mas due to the orbital motion of the Earth, which provides a distance estimate of roughly 350\u00a0light-years from the Sun. It is moving away from the Sun with a radial velocity of +40.5\u00a0km\/s.[4] About 2.6 million years ago, Rho Orionis made its perihelion passage at a distance of around 10 light-years (3.1 parsecs).[10]This is a single-lined spectroscopic binary system with an orbital period of 2.8\u00a0years and an eccentricity of 0.1.[9] The visible component is an evolved giant star of type K with a stellar classification of K0\u00a0III.[3] Its measured angular diameter is 2.19\u00b10.02\u00a0mas,[11] which, at its estimated distance yields a physical size of about 25 times the radius of the Sun.[7] It has 2.67 times the mass of the Sun and is about 650\u00a0million years old. The star is radiating 251 times the Sun’s luminosity from its enlarged photosphere at an effective temperature of 4,533\u00a0K.[6]^ This is the photocentric semi-major axis, from the motion shown by the observed “star” relative to distant objects, and in practice relative to the barycentre. This is always smaller than the orbital semi-major axis, dramatically smaller when the primary star is much more massive than the secondary or when it is not much brighter.References[edit]^ a b c d e van Leeuwen, F. (2007), “Validation of the new Hipparcos reduction”, Astronomy and Astrophysics, 474 (2): 653\u2013664, arXiv:0708.1752, Bibcode:2007A&A…474..653V, doi:10.1051\/0004-6361:20078357, S2CID\u00a018759600.^ a b c d Ducati, J. R. (2002). “VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson’s 11-color system”. CDS\/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237….0D.^ a b Houk, N.; Swift, C. (1999). “Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5”. Michigan Spectral Survey. 05: 0. Bibcode:1999MSS…C05….0H.^ a b Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (2005). “Local kinematics of K and M giants from CORAVEL\/Hipparcos\/Tycho-2 data. Revisiting the concept of superclusters”. Astronomy and Astrophysics. 430: 165. arXiv:astro-ph\/0409579. Bibcode:2005A&A…430..165F. doi:10.1051\/0004-6361:20041272. S2CID\u00a017804304.^ Smith, Graeme H.; Shetrone, Matthew D. (2000). “CaII K Emission-Line Asymmetry among Red Giants Detected by the ROSAT Satellite”. The Publications of the Astronomical Society of the Pacific. 112 (776): 1320. Bibcode:2000PASP..112.1320S. doi:10.1086\/316634.^ a b Luck, R. Earle (2015). “Abundances in the Local Region. I. G and K Giants”. The Astronomical Journal. 150 (3): 88. arXiv:1507.01466. Bibcode:2015AJ….150…88L. doi:10.1088\/0004-6256\/150\/3\/88. S2CID\u00a0118505114.^ a b Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol.\u00a01 (3rd\u00a0ed.), Birkh\u00e4user, ISBN\u00a03-540-29692-1. The radius (R*) is given by:2\u22c5R\u2217=(107\u22c52.19\u22c510\u22123)\u00a0AU0.0046491\u00a0AU\/R\u2a00\u224850.4\u22c5R\u2a00{displaystyle {begin{aligned}2cdot R_{*}&={frac {(107cdot 2.19cdot 10^{-3}) {text{AU}}}{0.0046491 {text{AU}}\/R_{bigodot }}}\\&approx 50.4cdot R_{bigodot }end{aligned}}}^ a b Soubiran, C.; Le Campion, J.-F.; Cayrel de Strobel, G.; Caillo, A. (June 2010), “The PASTEL catalogue of stellar parameters”, Astronomy and Astrophysics, 515: A111, arXiv:1004.1069, Bibcode:2010A&A…515A.111S, doi:10.1051\/0004-6361\/201014247, S2CID\u00a0118362423.^ a b Ren, S. (2013), “Hipparcos Photocentric Orbits of 72 Single-lined Spectroscopic Binaries”, The Astronomical Journal, 145 (3): 81, Bibcode:2013AJ….145…81R, doi:10.1088\/0004-6256\/145\/3\/81, S2CID\u00a0120199240^ Bailer-Jones, C. A. L. (March 2015), “Close encounters of the stellar kind”, Astronomy & Astrophysics, 575: 13, arXiv:1412.3648, Bibcode:2015A&A…575A..35B, doi:10.1051\/0004-6361\/201425221, S2CID\u00a059039482, A35.^ Richichi, A.; Percheron, I.; Khristoforova, M. (February 2005), “CHARM2: An updated Catalog of High Angular Resolution Measurements”, Astronomy and Astrophysics, 431 (2): 773\u2013777, Bibcode:2005A&A…431..773R, doi:10.1051\/0004-6361:20042039  "},{"@context":"http:\/\/schema.org\/","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/#breadcrumbitem","name":"Enzyklop\u00e4die"}},{"@type":"ListItem","position":2,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/rho-orionis-wikipedia\/#breadcrumbitem","name":"Rho Orionis – Wikipedia"}}]}]