Zeta Eridani
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 03h 15m 50.02656s |
| Declination | −08° 49′ 11.0220″ |
| Apparent magnitude (V) | 4.80 |
| Characteristics | |
| Spectral type | kA4hA9mA9V |
| U−B color index | +0.07 |
| B−V color index | +0.24 |
| Astrometry | |
| Radial velocity (Rv) | −5.8±4.2 km/s |
| Proper motion (μ) | RA: −0.35 mas/yr Dec.: +46.10 mas/yr |
| Parallax (π) | 29.72±0.29 mas |
| Distance | 110 ± 1 ly (33.6 ± 0.3 pc) |
| Absolute magnitude (MV) | 1.97 |
| Orbit | |
| Period (P) | 17.9297±0.0039 d |
| Eccentricity (e) | 0.14±0.03 |
| Periastron epoch (T) | 43,051.07±0.83 JD |
| Argument of periastron (ω) (secondary) | 122±11° |
| Semi-amplitude (K1) (primary) | 21.5±0.6 km/s |
| Details | |
| Mass | 1.85 M☉ |
| Radius | 1.97 R☉ |
| Luminosity | 10.3 L☉ |
| Surface gravity (log g) | 4.05 cgs |
| Temperature | 7,575 K |
| Metallicity [Fe/H] | 0.04 dex |
| Rotational velocity (v sin i) | 82 km/s |
| Age | 800 Myr |
| Other designations | |
| Zibal, ζ Eri, 13 Eri, FK5 1091, HD 20320, HIP 15197, HR 984, SAO 130387, BD−09°624, WDS J03158-0849A | |
| Database references | |
| SIMBAD | data |
Zeta Eridani (ζ Eridani, abbreviated Zeta Eri, ζ Eri) is a binary star in the constellation of Eridanus. With an apparent visual magnitude of 4.80, it is visible to the naked eye on a clear dark night. Based on parallax measurements taken during the Hipparcos mission, it is approximately 110 light-years from the Sun.
Zeta Eridani is the primary or 'A' component of a multiple star system designated WDS J03158-0849 (the secondary or 'B' component is 14 Eridani). Zeta Eridani's two components are therefore designated WDS J03158-0849 Aa and Ab. Aa is formally named Zibal /ˈzaɪbəl/, the traditional name for the system.