Beta Aquarii
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 21h 31m 33.53171s |
| Declination | −05° 34′ 16.2320″ |
| Apparent magnitude (V) | 2.87 |
| Characteristics | |
| Evolutionary stage | Yellow supergiant |
| Spectral type | G0 Ib |
| U−B color index | +0.58 |
| B−V color index | +0.84 |
| Astrometry | |
| Radial velocity (Rv) | 6.451±0.0627 km/s |
| Proper motion (μ) | RA: +18.77 mas/yr Dec.: −8.21 mas/yr |
| Parallax (π) | 5.9728±0.2147 mas |
| Distance | 541.8+18.4 −15.5 ly (166.12+5.64 −4.75 pc) |
| Absolute magnitude (MV) | −3.04 |
| Details | |
| Mass | 4.97±0.10 – 6.3 M☉ |
| Radius | 47.88+1.68 −1.81 R☉ |
| Luminosity | 2046±180 L☉ |
| Surface gravity (log g) | 2.05 cgs |
| Temperature | 5608±71 K |
| Metallicity [Fe/H] | −0.03 dex |
| Rotational velocity (v sin i) | 6.3±1.3 km/s |
| Age | 56 – 110±10 Myr |
| Other designations | |
| Sadalsuud, Saad el Sund, β Aqr, 22 Aqr, BD−06 5770, FK5 808, GC 30137, HD 204867, HIP 106278, HR 8232, SAO 145457, ADS 15050 A, CCDM J21316-0534A | |
| Database references | |
| SIMBAD | data |
Beta Aquarii is a single yellow supergiant star in the constellation of Aquarius. It has the official name Sadalsuud (/ˌsædəlˈsuːəd/) and the Bayer designation β Aquarii, abbreviated Beta Aqr or β Aqr. Based upon parallax measurements obtained during the Hipparcos mission, this component is located at a distance of approximately 540 light years (165 parsecs) from the Sun. It is drifting further away with a radial velocity of 6.5 km/s. The star serves as an IAU radial velocity standard.