The system bore the traditional name Alrescha (alternatively Al Rescha, Alrischa, Alrisha) derived from the Arabic الرشآء al-rishā’ "the cord" and less commonly Kaitain and Okda, the latter from the Arabic عقدة ʽuqdah "knot" (see Ukdah.[17] In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[18] to catalog and standardize proper names for stars. The WGSN approved the name Alrescha for the component Alpha Piscium A on 21 August 2016 and it is now so included in the List of IAU-approved Star Names.[15]
Alpha Piscium comprises a close binary with angular separation of presently 1.8" between the components. The main star or primary (Alpha Piscium A) is of magnitude +4.33 and spectral type A0p, while the companion or secondary (Alpha Piscium B) is magnitude 5.23 and belongs to spectral class A3m. The two stars take more than 3,000 years to orbit one another and they will make their closest approach to each other around 2060. One or both of the stars may be a spectroscopic binary as well. The stars have masses of 2.55 and 2.64 solar masses respectively and shine with a total luminosity of 55 and 63 times that of the Sun.
Alpha Piscium is catalogued as an α2 Canum Venaticorum variable, a type of variable star where the brightness changes are caused by the rotation of the star. The brightness varies by about 1/100th of a magnitude, identified from Hipparcos photometry.[4] The primary component is thought to be the source of the variations, and it has a period of 0.845 days which corresponds to the rotation period of the star. Variations with a period of 6.65 days have also been identified in the variations.[21]
Long-exposure observation
Stars that can set (not in a circumpolar constellation for the viewer) culminate at midnight – where viewed away from any polar region experiencing midnight sun – when at opposition, meaning they can be viewed from dusk until dawn. This applies to α Piscium on 21 October, in the current astronomical epoch.[22]
Half of the year from this date, 22 April, the star will be at conjunction above or below, the sun – apart by the star's declination (angle set out in table, right). The nearby days and months have most of the star's risen time during daylight.
References
^ abcdevan Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
^Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
^Gray, R. O.; Garrison, R. F. (July 1989), "The Late A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation", Astrophysical Journal Supplement, 70: 623, Bibcode:1989ApJS...70..623G, doi:10.1086/191349.
^ abSamus, N. N.; Durlevich, O. V.; et al. (2009), "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)", VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S, 1: B/gcvs, Bibcode:2009yCat....102025S.
^ abHartkopf, W. I.; et al. (June 30, 2006), Sixth Catalog of Orbits of Visual Binary Stars, United States Naval Observatory, retrieved 2017-06-02.
^ abcNetopil, Martin; Paunzen, Ernst; Hümmerich, Stefan; Bernhard, Klaus (2017), "An investigation of the rotational properties of magnetic chemically peculiar stars", Monthly Notices of the Royal Astronomical Society, 468 (3): 2745, arXiv:1703.05218, Bibcode:2017MNRAS.468.2745N, doi:10.1093/mnras/stx674, S2CID 119215348.
^ abGlagolevskij, Yu. V. (2019), "On Properties of Main Sequence Magnetic Stars", Astrophysical Bulletin, 74 (1): 66, Bibcode:2019AstBu..74...66G, doi:10.1134/S1990341319010073, S2CID 149900274.
^ abRoyer, F.; et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics, 393: 897–911, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763.
^ abcdefSikora, J.; Wade, G. A.; Power, J.; Neiner, C. (2019), "A volume-limited survey of MCP stars within 100 pc - I. Fundamental parameters and chemical abundances", Monthly Notices of the Royal Astronomical Society, 483 (2): 2300, arXiv:1811.05633, Bibcode:2019MNRAS.483.2300S, doi:10.1093/mnras/sty3105, S2CID 119089236.
^Kunitzsch, Paul; Smart, Tim (2006). A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations (2nd rev. ed.). Cambridge, Massachusetts: Sky Pub. ISBN978-1-931559-44-7.
^ ab"Naming Stars". IAU.org. Retrieved 2 March 2018.
^Hessman, F. V.; Dhillon, V. S.; Winget, D. E.; Schreiber, M. R.; Horne, K.; Marsh, T. R.; Guenther, E.; Schwope, A.; Heber, U. (2010). "On the naming convention used for multiple star systems and extrasolar planets". arXiv:1012.0707 [astro-ph.SR].
^Allen, Richard Hinckley (1899), Star-names and their meanings, G. E. Stechert, pp. 342−343.
^Division C WG Star Names, IAU Working Group on Star Names (WGSN), retrieved 22 May 2016.
^(in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日
^"MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
^Wraight, K. T.; Fossati, L.; Netopil, M.; Paunzen, E.; Rode-Paunzen, M.; Bewsher, D.; Norton, A. J.; White, Glenn J. (2012). "A photometric study of chemically peculiar stars with the STEREO satellites - I. Magnetic chemically peculiar stars". Monthly Notices of the Royal Astronomical Society. 420 (1): 757. arXiv:1110.6283. Bibcode:2012MNRAS.420..757W. doi:10.1111/j.1365-2966.2011.20090.x. S2CID 14811051.
^Ephemera table, rising and setting times In-the-Sky.org. Dominic C. Ford, 2011–2020; Cambridge UK.
March 11, 2023
alpha, piscium, piscium, binary, star, system, equatorial, constellation, pisces, based, upon, parallax, measurements, made, hipparcos, spacecraft, about, light, years, from, solar, system, pisciumlocation, piscium, circled, observation, dataepoch, j2000, equi. Alpha Piscium a Piscium is a binary star 6 system in the equatorial constellation of Pisces Based upon parallax measurements made by the Hipparcos spacecraft it is about 151 light years from the Solar System a PisciumLocation of a Piscium circled Observation dataEpoch J2000 0 Equinox J2000 0 ICRS Constellation PiscesRight ascension 02h 02m 02 81972s 1 Declination 02 45 49 5410 1 Apparent magnitude V 3 82 4 33 5 23 2 CharacteristicsSpectral type kA0hA7 Sr kA2hF2mF2 IV 3 Variable type a2 CVn 4 AstrometryProper motion m RA 32 45 1 mas yr Dec 0 04 1 mas yrParallax p 21 66 1 06 mas 1 Distance151 7 ly 46 2 pc Absolute magnitude MV 0 50 5 Orbit 6 Period P 3267 4 yrSemi major axis a 7 4 Eccentricity e 0 465Inclination i 113 4 Longitude of the node W 3 70 Periastron epoch T 2188 6Argument of periastron w secondary 147 9 Detailsa Psc AMass2 55 0 11 7 M Radius2 45 8 R Luminosity55 14 11 7 L Surface gravity log g 3 85 8 cgsTemperature10 233 507 483 7 KRotational velocity v sin i 81 9 km sa Psc BMass2 64 0 21 0 28 10 M Radius2 66 0 45 10 R Luminosity63 13 11 10 L Surface gravity log g 4 01 0 14 10 cgsTemperature10 000 710 10 KRotational velocity v sin i 84 9 km sAge331 159 153 10 MyrOther designationsAlrischa Kaitain Okda a Psc 113 Piscium BD 02 317 FK5 28 HIP 9487 SAO 110291 WDS J02020 0246AB 11 a Psc A HD 12447 HR 596 12 a Psc B HD 12446 HR 595 13 Database referencesSIMBADa Psca Psc Aa Psc BThe two components are designated Alpha Piscium A officially named Alrescha ae l ˈ r iː ʃ e the traditional name of the system 14 15 and B Contents 1 Nomenclature 2 Properties 3 Long exposure observation 4 ReferencesNomenclature Edita Piscium Latinised to Alpha Piscium is the star s Bayer designation The designations of the two components as Alpha Piscium A and B derive from the convention used by the Washington Multiplicity Catalog WMC for multiple star systems and adopted by the International Astronomical Union IAU 16 The system bore the traditional name Alrescha alternatively Al Rescha Alrischa Alrisha derived from the Arabic الرشآء al risha the cord and less commonly Kaitain and Okda the latter from the Arabic عقدة ʽuqdah knot see Ukdah 17 In 2016 the International Astronomical Union organized a Working Group on Star Names WGSN 18 to catalog and standardize proper names for stars The WGSN approved the name Alrescha for the component Alpha Piscium A on 21 August 2016 and it is now so included in the List of IAU approved Star Names 15 In Chinese 外屏 Wai Ping meaning Outer Fence refers to an asterism consisting of Alpha Piscium Delta Piscium Epsilon Piscium Zeta Piscium Mu Piscium Nu Piscium and Xi Piscium Consequently the Chinese name for Alpha Piscium itself is 外屏七 Wai Ping qi English the Seventh Star of Outer Fence 19 Properties EditAlpha Piscium comprises a close binary with angular separation of presently 1 8 between the components The main star or primary Alpha Piscium A is of magnitude 4 33 and spectral type A0p while the companion or secondary Alpha Piscium B is magnitude 5 23 and belongs to spectral class A3m The two stars take more than 3 000 years to orbit one another and they will make their closest approach to each other around 2060 One or both of the stars may be a spectroscopic binary as well The stars have masses of 2 55 and 2 64 solar masses respectively and shine with a total luminosity of 55 and 63 times that of the Sun A light curve for Alpha Piscium plotted from TESS data 20 Alpha Piscium is catalogued as an a2 Canum Venaticorum variable a type of variable star where the brightness changes are caused by the rotation of the star The brightness varies by about 1 100th of a magnitude identified from Hipparcos photometry 4 The primary component is thought to be the source of the variations and it has a period of 0 845 days which corresponds to the rotation period of the star Variations with a period of 6 65 days have also been identified in the variations 21 Long exposure observation EditStars that can set not in a circumpolar constellation for the viewer culminate at midnight where viewed away from any polar region experiencing midnight sun when at opposition meaning they can be viewed from dusk until dawn This applies to a Piscium on 21 October in the current astronomical epoch 22 Half of the year from this date 22 April the star will be at conjunction above or below the sun apart by the star s declination angle set out in table right The nearby days and months have most of the star s risen time during daylight References Edit a b c d e van Leeuwen F 2007 Validation of the new Hipparcos reduction Astronomy and Astrophysics 474 2 653 664 arXiv 0708 1752 Bibcode 2007A amp A 474 653V doi 10 1051 0004 6361 20078357 S2CID 18759600 Cowley A et al April 1969 A study of the bright A stars I A catalogue of spectral classifications Astronomical Journal 74 375 406 Bibcode 1969AJ 74 375C doi 10 1086 110819 Gray R O Garrison R F July 1989 The Late A Type Stars Refined MK Classification Confrontation with Stroemgren Photometry and the Effects of Rotation Astrophysical Journal Supplement 70 623 Bibcode 1989ApJS 70 623G doi 10 1086 191349 a b Samus N N Durlevich O V et al 2009 VizieR Online Data Catalog General Catalogue of Variable Stars Samus 2007 2013 VizieR On line Data Catalog B GCVS Originally Published in 2009yCat 102025S 1 B gcvs Bibcode 2009yCat 102025S 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 119257644 a b Hartkopf W I et al June 30 2006 Sixth Catalog of Orbits of Visual Binary Stars United States Naval Observatory retrieved 2017 06 02 a b c Netopil Martin Paunzen Ernst Hummerich Stefan Bernhard Klaus 2017 An investigation of the rotational properties of magnetic chemically peculiar stars Monthly Notices of the Royal Astronomical Society 468 3 2745 arXiv 1703 05218 Bibcode 2017MNRAS 468 2745N doi 10 1093 mnras stx674 S2CID 119215348 a b Glagolevskij Yu V 2019 On Properties of Main Sequence Magnetic Stars Astrophysical Bulletin 74 1 66 Bibcode 2019AstBu 74 66G doi 10 1134 S1990341319010073 S2CID 149900274 a b Royer F et al October 2002 Rotational velocities of A type stars in the northern hemisphere II Measurement of v sin i Astronomy and Astrophysics 393 897 911 arXiv astro ph 0205255 Bibcode 2002A amp A 393 897R doi 10 1051 0004 6361 20020943 S2CID 14070763 a b c d e f Sikora J Wade G A Power J Neiner C 2019 A volume limited survey of MCP stars within 100 pc I Fundamental parameters and chemical abundances Monthly Notices of the Royal Astronomical Society 483 2 2300 arXiv 1811 05633 Bibcode 2019MNRAS 483 2300S doi 10 1093 mnras sty3105 S2CID 119089236 alf Psc SIMBAD Centre de donnees astronomiques de Strasbourg retrieved 2017 08 04 alf Psc A SIMBAD Centre de donnees astronomiques de Strasbourg retrieved 2017 08 04 alf Psc B SIMBAD Centre de donnees astronomiques de Strasbourg retrieved 2017 08 04 Kunitzsch Paul Smart Tim 2006 A Dictionary of Modern star Names A Short Guide to 254 Star Names and Their Derivations 2nd rev ed Cambridge Massachusetts Sky Pub ISBN 978 1 931559 44 7 a b Naming Stars IAU org Retrieved 2 March 2018 Hessman F V Dhillon V S Winget D E Schreiber M R Horne K Marsh T R Guenther E Schwope A Heber U 2010 On the naming convention used for multiple star systems and extrasolar planets arXiv 1012 0707 astro ph SR Allen Richard Hinckley 1899 Star names and their meanings G E Stechert pp 342 343 Division C WG Star Names IAU Working Group on Star Names WGSN retrieved 22 May 2016 in Chinese AEEA Activities of Exhibition and Education in Astronomy 天文教育資訊網 2006 年 5 月 19 日 MAST Barbara A Mikulski Archive for Space Telescopes Space Telescope Science Institute Retrieved 8 December 2021 Wraight K T Fossati L Netopil M Paunzen E Rode Paunzen M Bewsher D Norton A J White Glenn J 2012 A photometric study of chemically peculiar stars with the STEREO satellites I Magnetic chemically peculiar stars Monthly Notices of the Royal Astronomical Society 420 1 757 arXiv 1110 6283 Bibcode 2012MNRAS 420 757W doi 10 1111 j 1365 2966 2011 20090 x S2CID 14811051 Ephemera table rising and setting times In the Sky org Dominic C Ford 2011 2020 Cambridge UK Retrieved from https en wikipedia org w index php title Alpha Piscium amp oldid 1096199644, wikipedia, wiki, book, books, library,
