Star in the constellation Boötes
20 Boötis Observation dataEpoch J2000 Equinox J2000 Constellation Boötes Right ascension 14h 19m 45.23505s [ 1] Declination +16° 18′ 24.9955″[ 1] Apparent magnitude (V)4.84[ 2] Characteristics Spectral type K3 III[ 3] B−Vcolor index ± 0.001[ 2] Astrometry Radial velocity (Rv )± 0.43[ 2] km/s Proper motion (μ)RA: –141.521 [ 1] mas /yr Dec.: +60.274 [ 1] mas /yr Parallax (π)17.8379± 0.1894 mas [ 1] Distance 183 ± 2 ly pc ) Absolute magnitude (MV )± 0.09[ 4] Details[ 4] Mass ± 0.19M ☉ Radius +0.26 [ 1] R ☉ Luminosity ± 0.66[ 1] L ☉ Surface gravity (log g )± 0.08cgs Temperature 4,472 K Metallicity 0.16 dex Rotation 848 days[ 5] Rotational velocity (v sin i )1.0[ 5] Age ± 2.28Gyr Other designations 20 Boo NSV 6631BD +16°2637FK5 3135GC 19334GJ 3841HD 125560HIP 70027HR 5370SAO 100980[ 6] Database references SIMBAD data
20 Boötis is a single[ 7] star in the northernconstellation ofBoötes , located 183 light years away from the Sun. It is visible to the naked eye as a faint, orange-hued star with anapparent visual magnitude of 4.84.[ 2] proper motion , traversing thecelestial sphere at the rate of 0.154 arc seconds per annum.[ 8] radial velocity of −8 km/s.[ 2]
This is an agingK-type giant star with astellar classification of K3 III.[ 3] red clump giant,[ 9] horizontal branch and is generating energy throughhelium fusion at itscore . The star is around five billion years old with 1.1[ 4] mass of the Sun and has expanded to 12[ 1] Sun's radius . It is radiating 52[ 1] luminosity of the Sun from its swollenphotosphere at aneffective temperature of 4,472 K.[ 4]
^a b c d e f g h i 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 e 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 Roman, Nancy G. (July 1952), "The Spectra of the Bright Stars of Types F5-K5",Astrophysical Journal ,116 : 122,Bibcode :1952ApJ...116..122R ,doi :10.1086/145598 ^a b c d da Silva, L.; et al. (November 2006), "Basic physical parameters of a selected sample of evolved stars",Astronomy and Astrophysics ,458 (2):609– 623,arXiv :astro-ph/0608160 Bibcode :2006A&A...458..609D ,doi :10.1051/0004-6361:20065105 ,S2CID 9341088 . ^a b Setiawan, J.; et al. (July 2004), "Precise radial velocity measurements of G and K giants. Multiple systems and variability trend along the Red Giant Branch",Astronomy and Astrophysics ,421 :241– 254,Bibcode :2004A&A...421..241S ,doi :10.1051/0004-6361:20041042-1 ^ "20 Boo" .SIMBAD Centre de données astronomiques de Strasbourg . RetrievedMay 8, 2019 .^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems",Monthly Notices of the Royal Astronomical Society ,389 (2):869– 879,arXiv :0806.2878 Bibcode :2008MNRAS.389..869E ,doi :10.1111/j.1365-2966.2008.13596.x S2CID 14878976 . ^ Lépine, Sébastien; Shara, Michael M. (March 2005), "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)",The Astronomical Journal ,129 (3):1483– 1522,arXiv :astro-ph/0412070 Bibcode :2005AJ....129.1483L ,doi :10.1086/427854 ,S2CID 2603568 . ^ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity",The Astrophysical Journal ,539 (2):732– 741,arXiv :astro-ph/0003329 Bibcode :2000ApJ...539..732A ,doi :10.1086/309278 ,S2CID 16673121
