40 Boötis
Star in the constellation Boötes
From Wikipedia, the free encyclopedia
40 Boötis is a single[8] star located 166.5 light years away from the Sun in the northern constellation of Boötes. It is visible to the naked eye as a dim, yellow-white hued star with an apparent visual magnitude of 5.64.[2] The star is moving away from the Earth with a heliocentric radial velocity of +12 km/s.[5]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 59m 36.94745s[1] |
| Declination | +39° 15′ 55.1994″[1] |
| Apparent magnitude (V) | 5.64[2] |
| Characteristics | |
| Evolutionary stage | giant[3] |
| Spectral type | F1 III–IV[4] |
| B−V color index | 0.336±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | +12.3±0.7[5] km/s |
| Proper motion (μ) | RA: −32.109[1] mas/yr Dec.: 41.246[1] mas/yr |
| Parallax (π) | 19.5911±0.0702 mas[1] |
| Distance | 166.5 ± 0.6 ly (51.0 ± 0.2 pc) |
| Absolute magnitude (MV) | 2.08[2] |
| Details | |
| Mass | 1.47[6] M☉ |
| Radius | 2.35+0.34 −0.13[1] R☉ |
| Luminosity | 11.585±0.054[1] L☉ |
| Surface gravity (log g) | 3.88[6] cgs |
| Temperature | 7,070±240[6] K |
| Metallicity [Fe/H] | −0.29[5] dex |
| Rotational velocity (v sin i) | 72.5[3] km/s |
| Age | 1.166[6] Gyr |
| Other designations | |
| 40 Boo, BD+39°2820, FK5 3182, HD 132772, HIP 73369, HR 5588, SAO 64449[7] | |
| Database references | |
| SIMBAD | data |
The Hipparcos catalogue (1997) lists a stellar classification of F1 III–IV,[9] matching the luminosity class of an aging star that is evolving into a giant.[3] Earlier, Cowley and Bidelman (1979) listed a class of F2 III,[10] while Sato and Kuji (1990) found a main sequence class of F0V.[11] It is around 1.2[6] billion years old with a relatively high rotation rate, showing a projected rotational velocity of 72.5 km/s.[3] The star has 1.5[6] times the mass of the Sun and 2.4[1] times the Sun's radius. It is radiating 11.6[1] times the luminosity of the Sun from its photosphere at an effective temperature of 7,070 K.[6]