Summary
104 Herculis is a solitary[11] variable star[2] located around 560[3] light years away from the Sun in the northern constellation of Hercules.[9] It has the variable star designation V669 Herculis and the Bayer designation A Herculis, while 104 Herculis is the Flamsteed designation. This object is visible to the naked eye as a dim, red-hued point of light with a baseline apparent visual magnitude of 4.96.[4] It is moving closer to the Earth with a heliocentric radial velocity of −1.2 km/s.[4]
 A visual band light curve for V669 Herculis. The main plot shows the long-term variation (plotted from data published by Tabur et al.[1]) and the inset plot shows the short-term periodic variation (adapted from Adelman and William[2]). | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 18h 11m 54.15649s[3] |
| Declination | +31° 24′ 19.2469″[3] |
| Apparent magnitude (V) | 4.96[4] |
| Characteristics | |
| Evolutionary stage | AGB[5] |
| Spectral type | M3 III[6] |
| B−V color index | 1.643±0.004[4] |
| Variable type | semiregular[7] |
| Astrometry | |
| Radial velocity (Rv) | −1.19±0.29[4] km/s |
| Proper motion (μ) | RA: −15.172[3] mas/yr Dec.: +25.084[3] mas/yr |
| Parallax (π) | 5.8167 ± 0.1769 mas[3] |
| Distance | 560 ± 20 ly (172 ± 5 pc) |
| Absolute magnitude (MV) | −1.15[4] |
| Details | |
| Radius | 85.80+6.65 −10.88[3] R☉ |
| Luminosity | 1,202.3±42.1[3] L☉ |
| Surface gravity (log g) | 0.99±0.29[8] cgs |
| Temperature | 3,535±24[8] K |
| Metallicity [Fe/H] | −0.08±0.10[8] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an aging red giant star on the asymptotic giant branch[5] with a stellar classification of M3 III.[6] It is a semiregular variable[7] with an amplitude of 0.14 in the B-band[12] and pulsation periods of 22.9 and 24.0 days.[1] Having exhausted the hydrogen at its core, the star has expanded to 86[3] times the Sun's radius. It is radiating 1,202[3] times the Sun's luminosity from its swollen photosphere at an effective temperature of 3,535 K.[8]
References edit
- ^ a b Tabur, V.; et al. (December 2009), "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society, 400 (4): 1945–1961, arXiv:0908.3228, Bibcode:2009MNRAS.400.1945T, doi:10.1111/j.1365-2966.2009.15588.x, S2CID 15358380.
- ^ a b Adelman, Saul J.; Harrell, William L. (2006), "BVRI Photometry of nz Gem, HD 73017, HD 77247, RT Vir and 104 Her", Baltic Astronomy, 15: 363–381, Bibcode:2006BaltA..15..363A.
- ^ a b c d e f g h i j 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 e f 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 Eggen, Olin J. (July 1992), "Asymptotic giant branch stars near the sun", Astronomical Journal, 104 (1): 275–313, Bibcode:1992AJ....104..275E, doi:10.1086/116239.
- ^ 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, S2CID 123149047.
- ^ a b Glass, I. S.; Van Leeuwen, F. (2007), "Semiregular variables in the solar neighbourhood", Monthly Notices of the Royal Astronomical Society, 378 (4): 1543–1549, arXiv:0704.3150, Bibcode:2007MNRAS.378.1543G, doi:10.1111/j.1365-2966.2007.11903.x, S2CID 14332208.
- ^ a b c d Prugniel, Ph.; et al. (July 2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv:1104.4952, Bibcode:2011A&A...531A.165P, doi:10.1051/0004-6361/201116769, S2CID 54940439.
- ^ a b "104 Her". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-17.
- ^ Kostjuk, N. D. (2004). "VizieR Online Data Catalog: HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index (Kostjuk, 2002)". VizieR On-line Data Catalog: IV/27A. Originally Published in: Institute of Astronomy of Russian Academy of Sciences (2002). 4027. Bibcode:2004yCat.4027....0K.
- ^ 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.
- ^ 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.