Beta Arietis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aries |
| Right ascension | 01h 54m 38.41099s |
| Declination | +20° 48′ 28.9133″ |
| Apparent magnitude (V) | 2.655 (2.712 + 5.789) |
| Characteristics | |
| Spectral type | A3V + G2V |
| U−B color index | +0.170 |
| B−V color index | +0.142 |
| Astrometry | |
| Radial velocity (Rv) | −1.9±0.9 km/s |
| Proper motion (μ) | RA: +98.74 mas/yr Dec.: −110.41 mas/yr |
| Parallax (π) | 55.827±0.308 mas |
| Distance | 58.4 ± 0.3 ly (17.91 ± 0.10 pc) |
| Absolute magnitude (MV) | 1.382 (1.444 + 4.521) |
| Orbit | |
| Companion | Beta Arietis B |
| Period (P) | 106.9954 ± 0.0005 days |
| Semi-major axis (a) | 36.1±0.3 mas |
| Eccentricity (e) | 0.903±0.012 |
| Inclination (i) | 44.7±1.3° |
| Longitude of the node (Ω) | 79.1±0.8° |
| Argument of periastron (ω) (secondary) | 209.1±1.2° |
| Details | |
| A | |
| Mass | 2.067±0.057 M☉ |
| Radius | 1.985 ± 0.229 R☉ |
| Luminosity | 20.9+5.4 −4.3 L☉ |
| Surface gravity (log g) | 4.0 cgs |
| Temperature | 8,759 K |
| Metallicity [Fe/H] | 0.16 dex |
| Rotational velocity (v sin i) | 73 km/s |
| Age | 447+261 −165 Myr |
| B | |
| Mass | 1.058±0.026 M☉ |
| Radius | 1.12 ± 0.064 R☉ |
| Luminosity | 1.29+0.16 −0.14 L☉ |
| Temperature | 5,811 K |
| Other designations | |
| Sheratan, Sharatan, Al Sharatain, 6 Arietis, BD+20°306, FK5 66, GJ 80, HD 11636, HIP 8903, HR 553, SAO 75012 | |
| Database references | |
| SIMBAD | data |
| ARICNS | data |
Beta Arietis is a binary star system in the constellation of Aries, marking the ram's second horn. Its identifier is a Bayer designation that is Latinized from β Arietis, and abbreviated Beta Ari or β Ari. It has the official name Sheratan, pronounced /ˈʃɛrətæn/. This system is visible to the naked eye as a point of light with a combined apparent visual magnitude of 2.65, making this the second-brightest star in the constellation. Located at a distance of 58.4 light-years (17.9 pc), the pair orbit each other with a period of 107 days.