| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 41m 38.75049s[1] |
| Declination | +08° 09′ 42.3409″[1] |
| Apparent magnitude (V) | 4.86[2] |
| Characteristics | |
| Spectral type | G7 IIIa[3] |
| B−Vcolor index | 0.992±0.038[2] |
| Astrometry | |
| Radial velocity (Rv) | −16.5±1.8[2] km/s |
| Proper motion (μ) | RA: −9.589[1]mas/yr Dec.: +3.906[1]mas/yr |
| Parallax (π) | 6.8757±0.2796 mas[1] |
| Distance | 470 ± 20 ly (145 ± 6 pc) |
| Absolute magnitude (MV) | −1.22[2] |
| Details | |
| Mass | 3.27[4] M☉ |
| Radius | 23.25+0.40 −0.49[1] R☉ |
| Luminosity | 274.9±12.6[1] L☉ |
| Surface gravity (log g) | 2.60[5] cgs |
| Temperature | 4,874+53 −41[1] K |
| Metallicity[Fe/H] | −0.10[5] dex |
| Rotational velocity (v sin i) | 6.5[6] km/s |
| Age | 370[4] Myr |
| Other designations | |
| 31 Boo,NSV 6769,BD+08°2903,FK5 3163,GC 19789,HD 129312,HIP 71832,HR 5480,SAO 120601[7] | |
| Database references | |
| SIMBAD | data |
31 Boötis is a single[8]star in the northernconstellation ofBoötes,[7] located 470 light years from the Sun.[1] It is visible to the naked eye as a faint, yellow-hued star with anapparent visual magnitude of 4.86.[2] The object is moving closer to the Earth with a heliocentricradial velocity of −16.5 km/s.[2] It was known to be part of a constellation between Virgo and Boötes namedMons Maenalus, it was also the brightest star in the constellation.
This is anevolvedgiant star with astellar classification of G7 IIIa.[3] It is a suspectedvariable star of unknown type,[9] and is anX-ray source.[10] The star is 370[4] million years old with 3.27[4] times themass of the Sun. Having exhausted the hydrogen at its core, the star has expanded to 23[1] times theSun's radius. It is radiating 275[1] times theluminosity of the Sun from its swollenphotosphere at aneffective temperature of 4,874 K.[1]
