Sigma Boötis

σ Boötis
Location of σ Boötes (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 14h 34m 40.817s
Declination +29° 44 42.48
Apparent magnitude (V) 4.46
Characteristics
Spectral type F4VkF2mF1
U−B color index −0.084
B−V color index +0.366
Variable type Suspected
Astrometry
Radial velocity (Rv)+0.37±0.09 km/s
Proper motion (μ) RA: +188.574 mas/yr
Dec.: +131.580 mas/yr
Parallax (π)63.4679±0.1173 mas
Distance51.39 ± 0.09 ly
(15.76 ± 0.03 pc)
Absolute magnitude (MV)3.52
Details
Mass1.48 M
1.18 M
Radius1.431±0.023 R
Luminosity3.461±0.042 L
Surface gravity (log g)4.30 cgs
Temperature6,594±55 K
Metallicity [Fe/H]−0.24 dex
Rotational velocity (v sin i)7.32 km/s
Age1.7 Gyr
2.42 Gyr
3.1 Gyr
Other designations
σ Boo, 28 Boötis, BD+30°2536, GC 19659, GJ 557, HD 128167, HIP 71284, HR 5447, SAO 83416, PPM 103421, CCDM 14347+2945, WDS J14347+2945A
Database references
SIMBADdata

Sigma Boötis is a single, yellow-hued star in the northern constellation of Boötes. Its name is a Bayer designation that is Latinized from σ Boötis, and abbreviated Sigma Boo or σ Boo. This star is visible to the naked eye with an apparent visual magnitude of 4.46. Located to the southeast of Rho Boötis, the dwarf Sigma may at first appear as a naked-eye double, but the angular proximity with Rho is merely line-of-sight. Sigma Boötis is located at a distance of 51.4 light-years (16 pc) from the Sun based on parallax. The star has a relatively high proper motion and is traversing the sky at the rate of 0.230 yr−1.