| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aries |
| Right ascension | 02h 15m 46.04981s[1] |
| Declination | +25° 46′ 58.5741″[1] |
| Apparent magnitude (V) | 5.79[2] |
| Characteristics | |
| Spectral type | F6 III-IV[3] or F6 IV-V[4] |
| B−Vcolor index | 0.439±0.005[2] |
| Astrometry | |
| Radial velocity (Rv) | +25.1±0.3[2] km/s |
| Proper motion (μ) | RA: +177.067[1]mas/yr Dec.: −64.694[1]mas/yr |
| Parallax (π) | 24.1949±0.1121 mas[1] |
| Distance | 134.8 ± 0.6 ly (41.3 ± 0.2 pc) |
| Absolute magnitude (MV) | 2.67[2] |
| Details | |
| Mass | 1.49±0.10[5] M☉ |
| Radius | 1.94±0.24[5] R☉ |
| Luminosity | 6.6±0.3[6] L☉ |
| Surface gravity (log g) | 4.03±0.05[5] cgs |
| Temperature | 6,416±60[5] K |
| Metallicity [Fe/H] | 0.27±0.05[5] dex |
| Rotational velocity (v sin i) | 8.0[6] km/s |
| Age | 2.19+0.44 −0.37[5] Gyr |
| Other designations | |
| 20 Ari,BD+25°373,GC 2707,HD 13871,HIP 10540,HR 656,SAO 75239[7] | |
| Database references | |
| SIMBAD | data |
20 Arietis is a single[8]star in the northernconstellation ofAries.20 Arietis is theFlamsteed designation. It has anapparent visual magnitude of 5.79, which is bright enough to be just faintly visible to the naked eye as a yellow-white hued star. The star is located approximately 137 light years away from the Sun based uponparallax. It has a relatively highproper motion, traversing thecelestial sphere at the rate of 0.188 arc seconds per annum.[9] 20 Arietis is receding from the Earth with a heliocentricradial velocity of +25 km/s.[2]
Gray et al. (2001) gave thestellar classification of 20 Arietis as F6 III-IV,[3] matching anF-type star withspectral traits intermediate between agiant and asubgiant star. Harlan (1969) had found a less-evolved class of F6 IV-V.[4] The star is around two billion years old[5] with an estimated 1.5 times themass of the Sun[5] and two times theSun's radius.[5] It is spinning with aprojected rotational velocity of 8.0 km/s[6] and has a higher than solarmetallicity.[5] The star is radiating 6.6[6] times theluminosity of the Sun from itsphotosphere at aneffective temperature of around 6,416 K.[5]
