Alpha Sagittarii
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 19h 23m 53.17483s |
| Declination | −40° 36′ 57.3705″ |
| Apparent magnitude (V) | +3.97 |
| Characteristics | |
| Spectral type | B8 V |
| U−B color index | −0.33 |
| B−V color index | −0.10 |
| Astrometry | |
| Radial velocity (Rv) | −0.7 km/s |
| Proper motion (μ) | RA: +30.49 mas/yr Dec.: −119.21 mas/yr |
| Parallax (π) | 17.94±0.22 mas |
| Distance | 182 ± 2 ly (55.7 ± 0.7 pc) |
| Absolute magnitude (MV) | +0.23 |
| Details | |
| Mass | 2.95 M☉ |
| Radius | 2.69 R☉ |
| Luminosity | 130 L☉ |
| Surface gravity (log g) | 4.11 cgs |
| Temperature | 12,387±421 K |
| Metallicity [Fe/H] | −0.02 dex |
| Rotational velocity (v sin i) | 71 km/s |
| Age | 33 Myr |
| Other designations | |
| Rukbat, α Sgr, CD−40°13245, FK5 728, GC 26737, HD 181869, HIP 95347, HR 7348, SAO 325060, PPM 353699 | |
| Database references | |
| SIMBAD | data |
Alpha Sagittarii (α Sagittarii, abbreviated Alpha Sgr, α Sgr), also named Rukbat /ˈrʌkbæt/, is a star in the constellation of Sagittarius.