Chi Ursae Majoris

Chi Ursae Majoris
Location of χ Ursae Majoris (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Ursa Major
Right ascension 11h 46m 03.01407s
Declination +47° 46 45.8553
Apparent magnitude (V) 3.72
Characteristics
Evolutionary stage Horizontal branch
Spectral type K0.5 IIIb
U−B color index +1.16
B−V color index +1.18
Astrometry
Radial velocity (Rv)−9.02±0.20 km/s
Proper motion (μ) RA: −138.297 mas/yr
Dec.: +28.66 mas/yr
Parallax (π)16.438±0.113 mas
Distance198 ± 1 ly
(60.8 ± 0.4 pc)
Absolute magnitude (MV)0.10±0.02
Details
Mass1.49 M
Radius23.15±0.21 R
Luminosity170.1±5.3 L
Surface gravity (log g)2.2 cgs
Temperature4,331±33 K
Metallicity [Fe/H]−0.44 dex
Rotational velocity (v sin i)2.3 km/s
Other designations
Alkaphrah, El Koprah, Taiyangshou, Chi UMa, χ UMa, 63 Ursae Majoris, BD+48°1966, FK5 441, HD 102224, HIP 57399, HR 4518, SAO 43886
Database references
SIMBADdata

Chi Ursae Majoris or χ Ursae Majoris, formally named Taiyangshou /ˌtˌjæŋˈʃ/, is a single star in the northern circumpolar constellation of Ursa Major. The star has an orange hue and is visible to the naked eye at night with an apparent visual magnitude of 3.72. It is located at a distance of approximately 198 light-years from the Sun based on parallax, but is drifting closer with a radial velocity of −9 km/s.