93 Herculis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 18h 00m 03.41611s[1] |
| Declination | +16° 45′ 03.2855″[1] |
| Apparent magnitude (V) | 4.67[2] |
| Characteristics | |
| Spectral type | K0.5IIb[3] |
| B−V color index | 1.254±0.007[2] |
| Astrometry | |
| Radial velocity (Rv) | −24.47±0.20[4] km/s |
| Proper motion (μ) | RA: −6.878[1] mas/yr Dec.: −9.696[1] mas/yr |
| Parallax (π) | 4.5894 ± 0.3311 mas[1] |
| Distance | 710 ± 50 ly (220 ± 20 pc) |
| Absolute magnitude (MV) | −1.85[2] |
| Details | |
| Radius | 50.53+1.41 −1.39[1] R☉ |
| Luminosity | 919±74[1] L☉ |
| Surface gravity (log g) | 1.8[5] cgs |
| Temperature | 4,471+63 −61[1] K |
| Metallicity [Fe/H] | −0.22[5] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
93 Herculis is a star located around 750[1] light years away from the Sun in the northern constellation of Hercules.[6] It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.67[2] The brightness of the star is diminished by an extinction of 0.21 due to interstellar dust.[7] It is moving closer to the Earth with a heliocentric radial velocity of −24.5 km/s.[4] This star, together with 95 Her, 102 Her, and 109 Her, made up the obsolete constellation Cerberus.[8]
This object has a stellar classification of K0.5IIb,[3] which indicates it is an evolved bright giant. With the supply of hydrogen at its core exhausted, the star has expanded to 51[1] times the Sun's radius. It is radiating around 919[1] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,471 K.[1] It is generally deficient in metal elements, but appears weakly enhanced in barium and other heavier elements.[5] This is a suspected barium star and hence may have a white dwarf companion in orbit.[9]
References
[edit]- ^ 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 at VizieR.
- ^ a b c d 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 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 de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ a b c Smith, G. R.; Harmer, D. L. (January 1982), "A differential curve-of-growth analysis of the candidate barium star 93 Her", Monthly Notices of the Royal Astronomical Society, 198: 273–280, Bibcode:1982MNRAS.198..273S, doi:10.1093/mnras/198.1.273.
- ^ a b "93 Her". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-16.
- ^ Famaey, B.; et al. (January 2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters", Astronomy and Astrophysics, 430 (1): 165–186, arXiv:astro-ph/0409579, Bibcode:2005A&A...430..165F, doi:10.1051/0004-6361:20041272, S2CID 17804304.
- ^ Ridpath, Ian, Ian Ridpath's Star Tales - Cerberus, retrieved 2019-06-16.
- ^ 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.
