Phi Piscium
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Pisces |
| Right ascension | 01h 13m 44.94617s |
| Declination | +24° 35′ 01.3249″ |
| Apparent magnitude (V) | 4.676 (A)/9.11 (B) |
| Characteristics | |
| φ Psc A | |
| Spectral type | K0III |
| B−V color index | +1.03 |
| φ Psc B | |
| Spectral type | K0 |
| U−B color index | +0.25 |
| B−V color index | +0.92 |
| Astrometry | |
| Radial velocity (Rv) | 5.9 km/s |
| Proper motion (μ) | RA: 16.901 mas/yr Dec.: −21.415 mas/yr |
| Parallax (π) | 8.1541±0.2028 mas |
| Distance | 400 ± 10 ly (123 ± 3 pc) |
| Absolute magnitude (MV) | −0.67 |
| Orbit | |
| Companion | φ Psc B |
| Period (P) | 7473±3 d yr |
| Eccentricity (e) | 0.815±0.005 |
| Argument of periastron (ω) (secondary) | 71.9±1.7° |
| Details | |
| A | |
| Radius | 23.63+0.66 −1.36 R☉ |
| Luminosity | 249.6±7.1 L☉ |
| Surface gravity (log g) | 2.75 cgs |
| Temperature | 4,720+142 −65 K |
| Metallicity [Fe/H] | −0.08 dex |
| Other designations | |
| Phi Psc, φ Psc, 85 Piscium, BD+23°158, FK5 2082, GC 1474, HD 7318, HIP 5742, HR 360, SAO 74571, PPM 90580, CCDM J01137+2435A, WDS J01137+2435A | |
| Database references | |
| SIMBAD | data |
Phi Piscium, Latinized from φ Piscium, is a quadruple star system approximately 380 light years away in the constellation Pisces. It consists of Phi Piscium A, with a spectral type of K0III, and Phi Piscium B. Phi Piscium A possesses a surface temperature of 3,500 to 5,000 kelvins. Some suggest the only visible companion in the Phi Piscium B sub-system is a late F dwarf star, while others suggest it is a K0 star. The invisible component of the Phi Piscium B sub-system is proposed to have a spectral type of M2V. The star system has a period of about 20½ years and has a notably high eccentricity of 0.815.