Star in the constellation Capricornus
Omega Capricorni Location of ω Capricorni (circled)
Observation dataEpoch J2000.0 Equinox J2000.0 (ICRS ) Constellation Capricornus Right ascension 20h 51m 49.29095s [ 1] Declination −26° 55′ 08.8912″[ 1] Apparent magnitude (V)+4.11[ 2] Characteristics Spectral type K4 III[ 3] U−Bcolor index +1.93[ 2] B−Vcolor index +1.64[ 2] Variable type Suspected[ 4] Astrometry Radial velocity (Rv )± 1.4[ 5] km/s Proper motion (μ)RA: −9.261[ 1] mas /yr Dec.: −1.598[ 1] mas /yr Parallax (π)3.1381± 0.3711 mas [ 1] Distance approx. 1,000 ly pc ) Absolute magnitude (MV )−2.7[ 6] Details Mass ± 0.9[ 7] M ☉ Radius +6.1 [ 1] R ☉ Luminosity +826 [ 1] L ☉ Surface gravity (log g )0.85[ 8] cgs Temperature +138 [ 1] K Metallicity −0.24[ 9] dex Rotational velocity (v sin i )4.68[ 8] Age ± 8.3[ 7] Myr Other designations ω Cap ,18 Cap ,CD −27°15082FK5 1546HD 198542HIP 102978HR 7980SAO 189781[ 10] Database references SIMBAD data
Omega Capricorni , which isLatinized from ω Capricorni, is astar in the southernconstellation Capricornus , near the southern constellation border withMicroscopium . It is an orange hued star that is faintly visible to the naked eye, having anapparent visual magnitude of +4.11.[ 2] parallax shift ofmas [ 1] light years from theSun . It is a candidate member of theUrsa Major Moving Group [ 11] peculiar velocity of± 1.9 km/srunaway star .[ 7]
InChinese ,天田 Tiān Tián Celestial Farmland 3 Piscis Austrini ,24 Capricorni andψ Capricorni .[ 12] Chinese name for ω Capricorni itself is天田二 Tiān Tián èr the First Star of Celestial Farmland .)[ 13]
This is anevolved K-type giant star with astellar classification of K4 III,[ 3] variable .[ 4] core exhausted, the star has expanded to about 172[ 1] radius of the Sun . It is 48[ 7] mass of the Sun .[ 7] [ 1] luminosity of the Sun from its bloatedphotosphere at aneffective temperature of 3,915 K.[ 1] barium star ,[ 6] s-process elements. This suggests that Omega Capricorni has an orbitingwhite dwarf companion.[ 14]
^a b c d e f g h i j k l Brown, A. G. A. ; et al. (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 atVizieR .^a b c d Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System",Astronomy and Astrophysics Supplement Series ,34 :1– 49,Bibcode :1978A&AS...34....1N . ^a b Houk, Nancy (1979),Michigan catalogue of two-dimensional spectral types for the HD stars , vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan,Bibcode :1982mcts.book.....H . ^a b NSV 13351 American Association of Variable Star Observers , retrieved2017-05-07 .^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system",Astronomy Letters ,32 (11):759– 771,arXiv :1606.08053 Bibcode :2006AstL...32..759G ,doi :10.1134/S1063773706110065 ,S2CID 119231169 . ^a b Mennessier, M. O.; et al. (October 1997), "Barium stars, galactic populations and evolution.",Astronomy and Astrophysics ,326 :722– 730,Bibcode :1997A&A...326..722M . ^a b c d e Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun",Monthly Notices of the Royal Astronomical Society 410 (1):190– 200,arXiv :1007.4883 Bibcode :2011MNRAS.410..190T ,doi :10.1111/j.1365-2966.2010.17434.x S2CID 118629873 . ^a b Hekker, S.; Meléndez, J. (December 2007), "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters",Astronomy and Astrophysics 475 (3):1003– 1009,arXiv :0709.1145 Bibcode :2007A&A...475.1003H ,doi :10.1051/0004-6361:20078233 ,S2CID 10436552 . ^ McWilliam, Andrew (1990), "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances",The Astrophysical Journal Supplement Series ,74 : 1075,Bibcode :1990ApJS...74.1075M ,doi :10.1086/191527 ^ "ome Cap" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2017-05-07 .^ Chupina, N. V.; et al. (June 2006), "Kinematic structure of the corona of the Ursa Major flow found using proper motions and radial velocities of single stars",Astronomy and Astrophysics ,451 (3):909– 916,Bibcode :2006A&A...451..909C ,doi :10.1051/0004-6361:20054009 ^ (in Chinese) 中國星座神話 , written by 陳久金. Published by 台灣書房出版有限公司, 2005,ISBN 978-986-7332-25-7 .^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 3 日 Archived 2011-05-21 at theWayback Machine ^ Gomez, A. E.; et al. (1997), "Absolute magnitudes and kinematics of barium stars",Astronomy and Astrophysics ,319 : 881,Bibcode :1997A&A...319..881G .
