[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/56-pegasi-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/en\/wiki24\/56-pegasi-wikipedia\/","headline":"56 Pegasi – Wikipedia","name":"56 Pegasi – Wikipedia","description":"From Wikipedia, the free encyclopedia Star in the constellation Pegasus 56 Pegasi Location of 56 Pegasi (circled) Observation dataEpoch J2000\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Equinox","datePublished":"2015-09-19","dateModified":"2015-09-19","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:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/b\/b9\/Pegasus_constellation_map.svg\/280px-Pegasus_constellation_map.svg.png","url":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/b\/b9\/Pegasus_constellation_map.svg\/280px-Pegasus_constellation_map.svg.png","height":"249","width":"280"},"url":"https:\/\/wiki.edu.vn\/en\/wiki24\/56-pegasi-wikipedia\/","about":["Wiki"],"wordCount":5944,"articleBody":"From Wikipedia, the free encyclopediaStar in the constellation Pegasus56 PegasiLocation of 56 Pegasi (circled)Observation dataEpoch J2000\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Equinox J2000ConstellationPegasusRight ascension23h 07m 06.74364s[1]Declination25\u00b0\u00a028\u2032\u00a005.788\u2033[1]Apparent\u00a0magnitude\u00a0(V)4.74[2]CharacteristicsSpectral\u00a0typeK0.5II:Ba1CN-2CH-0.5[3] + sdO[4][5]U\u2212B color index+1.14[2]B\u2212V color index+1.32[2]AstrometryRadial velocity (Rv)\u221227.55[6]\u00a0km\/sProper motion (\u03bc) RA:\u00a0\u22124.288[1]\u00a0mas\/yr Dec.:\u00a0\u221232.639[1]\u00a0mas\/yr Parallax (\u03c0)6.1131\u00a0\u00b1\u00a00.4108\u00a0mas[1]Distance530 \u00b1 40\u00a0ly (160 \u00b1 10\u00a0pc)Absolute\u00a0magnitude\u00a0(MV)\u22121.32[7]Orbit[5]Period (P)111.140\u00b10.14\u00a0dEccentricity (e)0Periastron epoch (T)51738.8\u00b10.5\u00a0MJDSemi-amplitude (K1)(primary)1.47\u00b10.04 km\/sDetails56 Peg AMass5.4[8]\u00a0M\u2609Radius41[9]\u00a0R\u2609Luminosity18.2 – 18.9[9]\u00a0L\u2609Surface gravity (log\u00a0g)0.50[10]\u00a0cgsTemperature4,185\u00b185[9]\u00a0KMetallicity [Fe\/H]\u22120.21[11]\u00a0dexRotational velocity (v\u00a0sin\u00a0i)4.4[12]\u00a0km\/sAge100\u00b1100[8]\u00a0MyrOther designationsDatabase referencesSIMBADdata56 Pegasi is a binary star system in the northern constellation of Pegasus. It is visible to the naked eye with a combined apparent visual magnitude of 4.74.[2] The system is approximately 590\u00a0light years away from the Sun based on parallax,[14] but is drifting closer with a radial velocity of \u221228\u00a0km\/s.[6] It is listed as a member of the Wolf 630 moving group.[15]The variable radial velocity of this star was announced in 1911 by W. W. Campbell. It is a single-lined spectroscopic binary in an assumed circular orbit with a period of 111.1\u00a0days. The a sin i value for this system is 0.01511\u00a0\u00b1\u00a00.00040\u00a0AU (2.26\u00a0\u00b1\u00a00.06\u00a0Gm), where a is the semimajor axis and i is the (unknown) orbital inclination. This value provides a lower bound on the true semimajor axis, which in this case is their actual separation.[5]The primary component is a peculiar bright giant with a stellar classification of K0.5 II: Ba1 CN-2 CH-0.5.[3] This notation indicates it is a K-type giant with some uncertainty about the classification, along with an overabundance of barium and underabundances of the CN and CH radicals. It is an active star,[16] roughly 100\u00a0million years old, with 5.4 times the Sun’s mass.[8] The star has expanded to 40[17] times the radius of the Sun and is radiating 680[11] times the Sun’s luminosity from its enlarged photosphere at an effective temperature of 4,416\u00a0K.[18]The system displays an excess of ultraviolet radiation that must be coming from the secondary companion. Simon et al. (1982) classified this object as a subdwarf O star.[4] Alternatively, it may be a white dwarf companion with an accretion disk.[19][5] Several puzzling features in the evolutionary history of this pair may be explained if the primary is a fast rotator being seen nearly pole-on. The star may have been spun up during a mass transfer episode with the secondary.[16]References[edit]^ a b c d e Brown, A. G. A.;  et\u00a0al. (Gaia collaboration) (August 2018). “Gaia Data Release 2: Summary of the contents and survey properties”. Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A…616A…1G. doi:10.1051\/0004-6361\/201833051. Gaia DR2 record for this source at VizieR.^ 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 Keenan, Philip C.; McNeil, Raymond C. (1989). “The Perkins catalog of revised MK types for the cooler stars”. Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS…71..245K. doi:10.1086\/191373.^ a b Simon, T.;  et\u00a0al. (1982). “On the reality of a boundary in the H-R diagram between late-type stars with and without high temperature outer atmospheres”. Astrophysical Journal. 257: 225. Bibcode:1982ApJ…257..225S. doi:10.1086\/159981.^ a b c d Griffin, R. F. (2006). “Spectroscopic binary orbits from photoelectric radial velocities – Paper 186: 56 Pegasi”. The Observatory. 126: 1. Bibcode:2006Obs…126….1G.^ a b Famaey, B.;  et\u00a0al. (2005). “Local kinematics of K and M giants from CORAVEL\/Hipparcos\/Tycho-2 data”. Astronomy & Astrophysics. 430: 165\u2013186. arXiv:astro-ph\/0409579. Bibcode:2005A&A…430..165F. doi:10.1051\/0004-6361:20041272. S2CID\u00a017804304.^ Frankowski, A.; Jorissen, A. (2006). “The puzzling case of 56 Pegasi: A fast rotator seen nearly pole-on”. The Observatory. 126: 25. arXiv:astro-ph\/0512036. Bibcode:2006Obs…126…25F.^ a b c Tetzlaff, N.;  et\u00a0al. (2011). “A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun”. Monthly Notices of the Royal Astronomical Society. 410 (1): 190\u2013200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111\/j.1365-2966.2010.17434.x. S2CID\u00a0118629873. Vizier catalog entry^ a b c Messineo, M.; Brown, A. G. A. (2019). “A Catalog of Known Galactic K-M Stars of Class I Candidate Red Supergiants in Gaia DR2”. The Astronomical Journal. 158 (1): 20. arXiv:1905.03744. Bibcode:2019AJ….158…20M. doi:10.3847\/1538-3881\/ab1cbd. S2CID\u00a0148571616.^ Soubiran, Caroline;  et\u00a0al. (2016). “The PASTEL catalogue: 2016 version”. Astronomy & Astrophysics. 591: A118. arXiv:1605.07384. Bibcode:2016A&A…591A.118S. doi:10.1051\/0004-6361\/201628497. S2CID\u00a0119258214.^ a b Anderson, E.; Francis, Ch. (2012). “XHIP: An extended hipparcos compilation”. Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL…38..331A. doi:10.1134\/S1063773712050015. S2CID\u00a0119257644. Vizier catalog entry^ De Medeiros, J. R.; Mayor, M. (1999). “A catalog of rotational and radial velocities for evolved stars”. Astronomy and Astrophysics Supplement Series. 139 (3): 433. arXiv:astro-ph\/0608248. Bibcode:1999A&AS..139..433D. doi:10.1051\/aas:1999401. Vizier catalog entry^ “56 Peg”. SIMBAD. Centre de donn\u00e9es astronomiques de Strasbourg. Retrieved 2019-07-01.^ 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. Vizier catalog entry^ McDonald, A. R. E.; Hearnshaw, J. B. (August 1983). “The Wolf 630 moving group of stars”. Monthly Notices of the Royal Astronomical Society. 204 (3): 841\u2013852. Bibcode:1983MNRAS.204..841M. doi:10.1093\/mnras\/204.3.841.^ a b Frankowski, A.; Jorissen, A. (February 2006). “The puzzling case of 56 Pegasi: a fast rotator seen nearly pole-on”. The Observatory. 126: 25\u201337. arXiv:astro-ph\/0512036. Bibcode:2006Obs…126…25F.^ van Belle, G. T.;  et\u00a0al. (2009). “Supergiant temperatures and linear radii from near-infrared interferometry”. Monthly Notices of the Royal Astronomical Society. 394 (4): 1925. arXiv:0811.4239. Bibcode:2009MNRAS.394.1925V. doi:10.1111\/j.1365-2966.2008.14146.x. S2CID\u00a0118372600.^ Mart\u00ednez, M. Isabel P\u00e9rez;  et\u00a0al. (2011). “The basal chromospheric Mg ii h+k flux of evolved stars: Probing the energy dissipation of giant chromospheres”. Monthly Notices of the Royal Astronomical Society. 414 (1): 418. arXiv:1102.4832. Bibcode:2011MNRAS.414..418P. doi:10.1111\/j.1365-2966.2011.18421.x. S2CID\u00a059268230. Vizier catalog entry^ Schindler, M.;  et\u00a0al. (December 1982). “Ultraviolet and X-ray detection of the 56 Pegasi system \/K0 IIp + WD\/ – Evidence for accretion of a cool stellar wind onto a white dwarf”. Astrophysical Journal, Part 1. 263: 269\u2013276. Bibcode:1982ApJ…263..269S. doi:10.1086\/160501.  "},{"@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\/56-pegasi-wikipedia\/#breadcrumbitem","name":"56 Pegasi – Wikipedia"}}]}]