R Horologii is a red giant star approximately 760 light-years away in the southern constellation of Horologium.[13] It is a Mira variable with a period of 404.83 days,[14] ranging from apparent magnitude 4.7 to 14.3—one of the largest ranges in brightness known of stars in the night sky visible to the unaided eye.[2] The star is losing mass at the rate of 5.9×10−7 M☉·y−1.[10]
 Location of R Horologii (R) in Horologium | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Horologium |
| Right ascension | 02h 53m 52.77010s[1] |
| Declination | −49° 53′ 22.7305″[1] |
| Apparent magnitude (V) | 4.7 – 14.3[2] |
| Characteristics | |
| Spectral type | M5-7e[3] |
| B−V color index | 1.044±0.011[4] |
| Variable type | Mira[5] |
| Astrometry | |
| Radial velocity (Rv) | 60.0±4.4[6] km/s |
| Proper motion (μ) | RA: 128.567 mas/yr[1] Dec.: 35.766 mas/yr[1] |
| Parallax (π) | 4.3236 ± 0.1524 mas[1] |
| Distance | 755.7 31.6 −6.0 ly (231.8 9.7 −9.3 pc)[7] |
| Details | |
| Mass | 0.94[8] M☉ |
| Radius | 635[9][a] R☉ |
| Luminosity | 8,500[9] L☉ |
| Surface gravity (log g) | −0.434[8] cgs |
| Temperature | 2,200[10][9] K |
| Metallicity [Fe/H] | 0.545[8] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
Notes
edit- ^ Applying the Stefan–Boltzmann law with a nominal solar effective temperature of 5,772 K:
- .
References
edit- ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b Privett, Grant; Jones, Kevin (2013). The Constellation Observing Atlas. New York, New York: Springer Science & Business Media. p. 102. ISBN 9781461476481.
- ^ Keenan, Philip C. (June 1966). "A Catalogue of Spectra of Mira Variables of Types ME and Se". Astrophysical Journal Supplement. 13: 333. Bibcode:1966ApJS...13..333K. doi:10.1086/190139.
- ^ 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.
- ^ Samus', N. N; Kazarovets, E. V; Durlevich, O. V; Kireeva, N. N; Pastukhova, E. N (2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
- ^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 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.
- ^ Bailer-Jones, C. A. L.; Rybizki, J.; Fouesneau, M.; Demleitner, M.; Andrae, R. (2021-03-01). "Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3". The Astronomical Journal. 161 (3): 147. arXiv:2012.05220. Bibcode:2021AJ....161..147B. doi:10.3847/1538-3881/abd806. ISSN 0004-6256. Data about this star can be seen here.
- ^ a b c Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; de Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. ISSN 0004-6361.
- ^ a b c Danilovich, T.; Teyssier, D.; Justtanont, K.; Olofsson, H.; Cerrigone, L.; Bujarrabal, V.; Alcolea, J.; Cernicharo, J.; Castro-Carrizo, A.; García-Lario, P.; Marston, A. (2015-09-01). "New observations and models of circumstellar CO line emission of AGB stars in the Herschel SUCCESS programme". Astronomy & Astrophysics. 581: A60. arXiv:1506.09065. doi:10.1051/0004-6361/201526705. ISSN 0004-6361.
- ^ a b Danilovich, T.; et al. (October 2017), "Sulphur-bearing molecules in AGB stars. I. The occurrence of hydrogen sulphide", Astronomy & Astrophysics, 606: 14, arXiv:1707.06003, Bibcode:2017A&A...606A.124D, doi:10.1051/0004-6361/201731203, S2CID 55533463, A124
- ^ "R Horologii". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 18 March 2016.
- ^ "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
- ^ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- ^ Templeton, M. R.; Mattei, J. A.; Willson, L. A. (2005). "Secular Evolution in Mira Variable Pulsations". The Astronomical Journal. 130 (2): 776–788. arXiv:astro-ph/0504527. Bibcode:2005AJ....130..776T. doi:10.1086/431740. S2CID 359940.
External links
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