Star in the constellation Hercules
G Herculis Observation dataEpoch J2000 Equinox J2000 Constellation Hercules Right ascension 16h 28m 38.54859s [ 2] Declination +41° 52′ 54.0406″[ 2] Apparent magnitude (V)4.3 - 6.3[ 3] Characteristics Evolutionary stage AGB [ 4] Spectral type M6− III[ 5] B−Vcolor index ± 0.024[ 6] Variable type SRb [ 3] Astrometry Radial velocity (Rv )± 0.38[ 6] km/s Proper motion (μ)RA: +30.16[ 2] mas /yr Dec.: −5.14[ 2] mas /yr Parallax (π)9.21± 0.18 mas [ 2] Distance 354 ± 7 ly pc ) Absolute magnitude (MV )−0.41[ 7] Orbit [ 4] Period (P)± 21.1 dEccentricity (e)± 0.11Periastron epoch (T)± 43.9 HJD Argument of periastron (ω)± 21Semi-amplitude 1 )± 0.3Details g Her A Mass ± 0.30[ 8] M ☉ Radius 230[ 9] R ☉ Luminosity 5,395[ 9] L ☉ Surface gravity (log g )0.20[ 10] cgs Temperature ± 23[ 9] K Metallicity −0.01[ 10] dex Other designations g Her 30 Her BD +42°2714FK5 3303HD 148783HIP 80704HR 6146SAO 46108[ 11] Database references SIMBAD data
g Herculis is abinary star [ 12] constellation ofHercules . It has theFlamsteed designation 30 Herculis , whileg Herculis is theBayer designation . This system is visible to thenaked eye as a faint, red-hued point of light. Based upon a measuredparallax ofmas light years away from the Sun. The system is moving further from the Earth with a heliocentricradial velocity of 1.5 km/s.[ 6]
This is a single-linedspectroscopic binary with anorbital period of 2.310 years and aneccentricity of 0.37.[ 4] red giant on theasymptotic giant branch [ 4] stellar classification of M6− III.[ 5] semiregular variable of subtype SRb, which ranges between visual magnitudes 4.3 and 6.3 over 89.2 days.[ 3] [ 13] [ 4] [ 14]
^ "Light Curve" ,Hipparcos ESA , ESA, retrieved20 September 2022 .^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&A...474..653V ,doi :10.1051/0004-6361:20078357 ,S2CID 18759600 . ^a b c Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars",Astronomy Reports , 5.1,61 (1):80– 88,Bibcode :2017ARep...61...80S ,doi :10.1134/S1063772917010085 ,S2CID 125853869 . ^a b c d e Hinkle, Kenneth H.; et al. (February 2002), "Velocity Observations of Multiple-Mode Asymptotic Giant Branch Variable Stars",The Astronomical Journal ,123 (2):1002– 1012,Bibcode :2002AJ....123.1002H ,doi :10.1086/338314 ^a b Keenan, P.; McNeil, R. (October 1989), "The Perkins catalog of revised MK types for the cooler stars",Astrophysical Journal Supplement Series ,71 :245– 266,Bibcode :1989ApJS...71..245K ,doi :10.1086/191373 ,S2CID 123149047 . ^a b c 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 . ^ Schiavon, Ricardo P. (July 2007), "Population Synthesis in the Blue. IV. Accurate Model Predictions for Lick Indices and UBV Colors in Single Stellar Populations",The Astrophysical Journal Supplement Series ,171 (1):146– 205,arXiv :astro-ph/0611464 Bibcode :2007ApJS..171..146S ,doi :10.1086/511753 ,S2CID 13946698 . ^ Halabi, Ghina M.; Eid, Mounib El (August 2015), "Exploring masses and CNO surface abundances of red giant stars",Monthly Notices of the Royal Astronomical Society ,451 (3):2957– 2967,arXiv :1507.01517 Bibcode :2015MNRAS.451.2957H ,doi :10.1093/mnras/stv1141 S2CID 118707332 . ^a b c Ayres, Thomas (2023-05-01), "In the Trenches of the Solar-Stellar Connection. VII. Wilson-Bappu 2022",The Astrophysical Journal Supplement Series ,266 (1): 6,Bibcode :2023ApJS..266....6A ,doi :10.3847/1538-4365/acb535 ISSN 0067-0049 g Herculis' database entry atVizieR .^a b Ramírez, Solange V.; et al. (2000), "Stellar Iron Abundances at the Galactic Center",The Astrophysical Journal ,537 (1):205– 220,arXiv :astro-ph/0002062 Bibcode :2000ApJ...537..205R ,doi :10.1086/309022 ,S2CID 14713550 . ^ "g Her" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2019-06-13 .^ 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 . ^ Otero, Sebastian Alberto (June 28, 2011),"g Herculis" ,AAVSO Website ,American Association of Variable Star Observers , retrieved20 July 2014 ^ Posch, Th.; et al. (October 2002), "On the origin of the 19.5 μ m feature. Identifying circumstellar Mg-Fe-oxides",Astronomy and Astrophysics ,393 :L7 – L10 ,Bibcode :2002A&A...393L...7P ,doi :10.1051/0004-6361:20021127
