Castor

The position of Castor within the Gemini Constellation.
Observation data
Epoch J2000      Equinox J2000
Constellation Gemini
Right ascension 07
Declination +31° 53′ 17.8160″
Apparent magnitude (V) 1.93 / 2.97
Characteristics
Spectral type A1 V + A2 Vm
U−B color index 0.02
B−V color index 0.04
Astrometry
Radial velocity (Rv) +6.0 / –1.2 km/s
Proper motion (μ) RA: –191.45 mas/yr
Parallax (π) 64.12 ± 3.75mas
Distance 51 ± 3 ly
(15.6 ± 0.9 pc)
Details
α Gem Aa
Mass 2.76M
Radius 2.4R
Surface gravity (log g) 4.2
Temperature 10,286K
Metallicity [Fe/H] 0.98dex
Rotational velocity (v sin i) 18 km/s
α Gem Ba
Mass 2.98M
Radius 3.3R
Surface gravity (log g) 4.0
Temperature 8,842K
Rotational velocity (v sin i) 33 km/s
Other designations
Castor, α Gem, 66 Gem, YY Gem, BD +32 1581/2, FK5 287, GCTP 1785.00, Gl 278, HD 60178/60179, HIP 36850, HR 2891, LTT 12038, SAO 60198.
Database references
SIMBAD Castor Aa data
Database references
SIMBAD Castor Ba data

Get more info about Castor in Wikipedia

This article uses material from the Wikipedia article
Castor, which is released under the Creative Commons Attribution-Share-Alike License 3.0