HD 115310, also known by its Bayer designation r Centauri, is a star in the southern constellation Centaurus. It is an orange-hued star that is visible to the naked eye with an apparent visual magnitude that ranges around +5.12.[2] Based upon parallax measurements, it is located approximately 257 light years away. It is drifting further from the Sun with a radial velocity of +12.9 km/s.[4]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Centaurus |
| Right ascension | 13h 16m 53.13228s[1] |
| Declination | −31° 30′ 22.3332″[1] |
| Apparent magnitude (V) | +5.12[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch |
| Spectral type | K1III[3] |
| B−V color index | 0.94[2] |
| Astrometry | |
| Radial velocity (Rv) | +12.9[4] km/s |
| Proper motion (μ) | RA: +34.179[1] mas/yr Dec.: −47.615[1] mas/yr |
| Parallax (π) | 12.7119 ± 0.1426 mas[1] |
| Distance | 257 ± 3 ly (78.7 ± 0.9 pc) |
| Absolute magnitude (MV) | +0.70 |
| Details[2] | |
| Mass | 2.71±0.19 M☉ |
| Radius | 10.8±0.8 R☉ |
| Luminosity | 67.11±6.91 L☉ |
| Surface gravity (log g) | 2.63 cgs |
| Temperature | 5,060 K |
| Metallicity [Fe/H] | −0.15[5] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
This object is an aging K-type giant star with a stellar classification of K1III.[3] It is classified as a red clump giant, suggesting it is on the horizontal branch undergoing core helium fusion.[5] The star has 2.7 times the mass of the Sun and has expanded to 11 times the Sun's radius. It is radiating 67 times the luminosity of the Sun from its swollen photosphere at an effective temperature of 5,060 K.[2]
References
edit- ^ a b c d e 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 Bluhm, P.; et al. (October 2016), "New spectroscopic binary companions of giant stars and updated metallicity distribution for binary systems", Astronomy & Astrophysics, 593: 17, arXiv:1608.08260, Bibcode:2016A&A...593A.133B, doi:10.1051/0004-6361/201628459, S2CID 56087624, A133.
- ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982mcts.book.....H.
- ^ a b Wilson, Ralph Elmer (1953), "General catalogue of stellar radial velocities", Washington, Carnegie Institution of Washington: 0, Bibcode:1953GCRV..C......0W.
- ^ a b 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.
- ^ "HD 115310". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-06.