Kappa Eridani
Star in the constellation Eridanus
From Wikipedia, the free encyclopedia
Kappa Eridani, Latinized from κ Eridani, is a solitary star in the constellation Eridanus. With an apparent visual magnitude of 4.25,[2] 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,[1] it is roughly 510 light years distant from the Sun.
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 02h 26m 59.12177s[1] |
| Declination | −47° 42′ 13.8247″[1] |
| Apparent magnitude (V) | 4.25[2] |
| Characteristics | |
| Spectral type | B7 IV[3] |
| U−B color index | −0.50[2] |
| B−V color index | −0.14[2] |
| Astrometry | |
| Radial velocity (Rv) | +25.5±0.5[4] km/s |
| Proper motion (μ) | RA: +19.32[1] mas/yr Dec.: −5.54[1] mas/yr |
| Parallax (π) | 6.42±0.15 mas[1] |
| Distance | 510 ± 10 ly (156 ± 4 pc) |
| Absolute magnitude (MV) | −1.72[5] |
| Details[3] | |
| Mass | 5.0±0.8 M☉ |
| Radius | 6[6][7] R☉ |
| Luminosity | 1,175 L☉ |
| Surface gravity (log g) | 3.5±0.1 cgs |
| Temperature | 14,700±400 K |
| Metallicity [Fe/H] | 0.02±0.06[8] 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[9] | |
| Database references | |
| SIMBAD | data |
This appears to be an evolving B-type subgiant star with a stellar classification of B7 IV.[3] The measured angular diameter is 0.346±0.008 mas.[8] At an estimated distance of Kappa Eridani, this yields a physical size of about six times the radius of the Sun.[6] 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.[3]
