| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 02 26 59.12177 |
| Declination | −47° 42′ 13.8247″ |
| Apparent magnitude (V) | 4.25 |
| Characteristics | |
| Spectral type | B7 IV |
| U−B color index | −0.50 |
| B−V color index | −0.14 |
| Astrometry | |
| Radial velocity (Rv) | +25.5±0.5 km/s |
| Proper motion (μ) | RA: +19.32 mas/yr Dec.: −5.54 mas/yr |
| Parallax (π) | 6.42 ± 0.15 mas |
| Distance | 510 ± 10 ly (156 ± 4 pc) |
| Absolute magnitude (MV) | −1.72 |
| Details | |
| Mass | 5.0±0.8 M☉ |
| Radius | 6 R☉ |
| Luminosity | 1,175 L☉ |
| Surface gravity (log g) | 3.5±0.1 cgs |
| Temperature | 14,700±400 K |
| Metallicity | 0.02±0.06 dex |
| Rotational velocity (v sin i) | 10±8 km/s |
| Age | 93 Myr |
| Other designations | |
| κ Eri, CD-48° 637, FK5 86, HD 15371, HIP 11407, HR 721, SAO 215906. | |
| Database references | |
| SIMBAD | data |
Kappa Eridani, Latinized from κ Eridani, is a solitary star in the constellation Eridanus. With an apparent visual magnitude of 4.25, it is bright enough to be visible to the naked eye on a dark night. Based upon an annual parallax shift of 0.00642 arc seconds, it is roughly 510 light years distant from the Sun.
This appears to be an evolving B-type subgiant star with a stellar classification of B7 IV. The measured angular diameter is 0.346±0.008 mas. At an estimated distance of Kappa Eridani, this yields a physical size of about six times the radius of the Sun. It has five times the Sun's mass, and radiates 1,175 times the solar luminosity from its outer atmosphere at an effective temperature of 14,700 K. Kappa Eridani is spinning with a projected rotational velocity of 10 km/s and is around 93 million years old.
References
- ^ 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.
- ^ 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.
- ^ Levenhagen, R. S.; Leister, N. V. (2006), "Spectroscopic Analysis of Southern B and Be Stars", Monthly Notices of the Royal Astronomical Society, 371 (1): 252–62, arXiv:astro-ph/0606149, Bibcode:2006MNRAS.371..252L, doi:10.1111/j.1365-2966.2006.10655.x, S2CID 16492030.
- 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.
- 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.
- ^ Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1.
The radius (R*) is given by: - Pasinetti Fracassini, L. E.; et al. (2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy & Astrophysics, 367 (2): 521–24, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
- ^ Niemczura, E. (June 2003), "Metallicities of the SPB stars from the IUE ultraviolet spectra", Astronomy and Astrophysics, 404 (2): 689–700, Bibcode:2003A&A...404..689N, doi:10.1051/0004-6361:20030546.
- "kap Eri". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-10-30.
