Upsilon Boötis
Star in the constellation Boötes / From Wikipedia, the free encyclopedia
Upsilon Boötis (υ Boötis) is a single,[8] orange-hued star in the northern constellation of Boötes. It is a fourth[2] magnitude star that is visible to the naked eye. Based upon an annual parallax shift of 12.38 mas as seen from the Earth,[1] it is located about 263 light years from the Sun. The star is moving closer to the Sun with a radial velocity of −6 km/s.[4]
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Boötes |
Right ascension | 13h 49m 28.64078s[1] |
Declination | +15° 47′ 52.4603″[1] |
Apparent magnitude (V) | 4.023[2] |
Characteristics | |
Spectral type | K5.5 III[3] |
U−B color index | +1.893[2] |
B−V color index | +1.518[2] |
Astrometry | |
Radial velocity (Rv) | −5.94±0.26[4] km/s |
Proper motion (μ) | RA: −94.22±0.19[1] mas/yr Dec.: +41.07±0.14[1] mas/yr |
Parallax (π) | 12.38 ± 0.23 mas[1] |
Distance | 263 ± 5 ly (81 ± 2 pc) |
Absolute bolometric magnitude (Mbol) | −1.44±0.14[5] |
Details | |
Mass | 1.11±0.33[6] M☉ |
Radius | 38.44±2.37[5] R☉ |
Luminosity | 332±54[6] L☉ |
Surface gravity (log g) | 1.5[4] cgs |
Temperature | 3,920[6] K |
Metallicity [Fe/H] | −0.23[4] dex |
Rotational velocity (v sin i) | 5.1[4] km/s |
Other designations | |
Database references | |
SIMBAD | data |
This is an evolved K-type giant star with a stellar classification of K5.5 III.[3] Astroseismology was used to obtain a mass estimate of 1.11 times the mass of the Sun,[6] while interferometric measurements give a size of about 38[5] times the Sun's radius. It is radiating about 332[6] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,920 K.[6]