Xi Coronae Borealis

ξ Coronae Borealis
Location of ξ Coronae Borealis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Corona Borealis
Right ascension 16h 22m 05.82391s
Declination +30° 53 31.1837
Apparent magnitude (V) 4.85
Characteristics
Evolutionary stage red clump
Spectral type G9 IIIFe−0.5
U−B color index +0.80
B−V color index +0.97
Astrometry
Radial velocity (Rv)−29.20±0.16 km/s
Proper motion (μ) RA: −97.43 mas/yr
Dec.: +107.45 mas/yr
Parallax (π)17.78±0.25 mas
Distance183 ± 3 ly
(56.2 ± 0.8 pc)
Absolute magnitude (MV)+1.04
Details
Mass2.36 M
Radius8 R
Luminosity36 L
Surface gravity (log g)2.9 cgs
Temperature4,853±5 K
Metallicity [Fe/H]−0.08 dex
Rotational velocity (v sin i)2.8 km/s
Age676 Myr
Other designations
ξ CrB, 19 CrB, BD+31°2845, HD 147677, HIP 80181, HR 6103, SAO 65254, WDS J16221+3054A
Database references
SIMBADdata

Xi Coronae Borealis (ξ CrB) is a binary star system in the northern constellation of Corona Borealis. It is visible to the naked eye with a combined apparent visual magnitude of 4.85. Based upon an annual parallax shift of 17.78 mas as seen from the Earth, it is located about 183 light years from the Sun.

As of 2009, the pair had an angular separation of 91 mas along a position angle of 139.4°. The brighter member, component Aa, is an evolved G-type giant star with a stellar classification of G9 III. It is a red clump star that is generating energy by helium fusion at its core. The star has an estimated 2.36 times the mass of the Sun and has expanded to 8 times the Sun's radius. It is radiating 36 times the solar luminosity from its photosphere at an effective temperature of 4,853 K.