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 |
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]
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]