Kappa Librae is a star system in the zodiac constellation of Libra. Its name is a Bayer designation that is Latinized from κ Librae, and abbreviated Kappa Lib or κ Lib. Its apparent visual magnitude is 4.72,[3] so it can be seen with the naked eye. The annual parallax shift of 10.57 mas[2] indicates it is roughly 310 light years away. It is positioned 0.02 degrees south of the ecliptic.
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Libra[1] |
| Right ascension | 15h 41m 56.79858s[2] |
| Declination | −19° 40′ 43.7745″[2] |
| Apparent magnitude (V) | 4.72[3] |
| Characteristics | |
| Spectral type | K5 III[4] |
| U−B color index | +1.94[3] |
| B−V color index | +1.58[3] |
| Astrometry | |
| Radial velocity (Rv) | −4.5±1.5[5] km/s |
| Proper motion (μ) | RA: −32.06[2] mas/yr Dec.: −103.15[2] mas/yr |
| Parallax (π) | 10.57±1.40 mas[2] |
| Distance | approx. 310 ly (approx. 90 pc) |
| Absolute magnitude (MV) | −0.62[1] |
| Details | |
| Mass | 1.6[6] M☉ |
| Radius | 38[7] R☉ |
| Luminosity | 388[8] L☉ |
| Surface gravity (log g) | 1.35[6] cgs |
| Temperature | 3,875[7] K |
| Metallicity [Fe/H] | −0.39[6] dex |
| Other designations | |
| κ Lib, 43 Lib, BD−19°4188, FK5 1413, HD 139997, HIP 76880, HR 5838, SAO 159442[9] | |
| Database references | |
| SIMBAD | data |
The star shows acceleration components in its proper motion, indicating with high probability that it is an astrometric binary.[10] The visible component is an evolved K-type giant star with a stellar classification of K5 III.[4] It is a suspected variable star with a brightness that ranges between 4.70 and 4.75.[11] Kappa Librae is 38 times larger than the Sun,[7] and is radating 388 times the solar luminosity[8] from its outer atmosphere at an effective temperature of 3,875 K.[7]
In Chinese astronomy, Kappa Librae is called 日, Pinyin: Rì, meaning Sun, because this star is marking itself and stand alone in Sun asterism, Room mansion (see: Chinese constellations).[12]
References
edit- 1 2 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. XHIP record for this object at VizieR.
- 1 2 3 4 5 6 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.
- 1 2 3 4 Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
- 1 2 Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
- ↑ 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.
- 1 2 3 Kaltenegger, L.; Faherty, J. K. (2021), "Past, present and future stars that can see Earth as a transiting exoplanet", Nature, 594 (7864): 505–507, arXiv:2107.07936, Bibcode:2021Natur.594..505K, doi:10.1038/s41586-021-03596-y, PMID 34163055
- 1 2 3 4 McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017-10-01), "Fundamental parameters and infrared excesses of Tycho-Gaia stars", Monthly Notices of the Royal Astronomical Society, 471: 770–791, arXiv:1706.02208, Bibcode:2017MNRAS.471..770M, doi:10.1093/mnras/stx1433, ISSN 0035-8711. Kappa Librae's database entry at VizieR.
- 1 2 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.
- ↑ "kap Lib". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-01-30.
{{cite web}}: CS1 maint: postscript (link) - ↑ Makarov, V. V.; Kaplan, G. H. (May 2005), "Statistical Constraints for Astrometric Binaries with Nonlinear Motion" (PDF), The Astronomical Journal, 129 (5): 2420–2427, Bibcode:2005AJ....129.2420M, doi:10.1086/429590, archived from the original on September 24, 2017.
- ↑ Samus, N. N.; Durlevich, O. V.; et al. (2004), "Combined General Catalogue of Variable Stars (GCVS4.2)", Vizier Online Data Catalog, Bibcode:2004yCat.2250....0S.
- ↑ Ian Ridpath's Startales - Libra the Scales