Mu Geminorum

μ Geminorum
Location of μ Geminorum (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Gemini
Right ascension 06h 22m 57.62686s
Declination +22° 30 48.8979
Apparent magnitude (V) 2.75 - 3.02
Characteristics
Evolutionary stage AGB
Spectral type M3 III
U−B color index +1.924
B−V color index +1.643
Variable type LB
Astrometry
Radial velocity (Rv)+54.38±0.24 km/s
Proper motion (μ) RA: +56.39 mas/yr
Dec.: −110.03 mas/yr
Parallax (π)14.08±0.71 mas
Distance230 ± 10 ly
(71 ± 4 pc)
Absolute magnitude (MV)−1.42
Details
Mass1.9±0.5 M
Radius107.7 R
Luminosity1,692 L
Surface gravity (log g)0.82±0.09 cgs
Temperature3,643 K
Metallicity [Fe/H]−0.03±0.03 dex
Rotational velocity (v sin i)8.4 km/s
Other designations
Tejat, Mu Gem, μ Gem, 13 Geminorum, BD+22°1304, FK5 241, HD 44478, HIP 30343, HR 2286, SAO 78297, ADS 4990A, CCDM J06230+2230A, WDS J06230+2231A
Database references
SIMBADdata

Mu Geminorum or μ Geminorum, formally named Tejat (/ˈtət/), is a single star in the northern constellation of Gemini. From parallax measurements obtained during the Hipparcos mission, it is roughly 230 light-years (71 parsecs) distant from the Sun. The position of the star near the ecliptic means that it is subject to lunar occultations.

Mu Geminorum forms the primary or 'A' component of a double star system designated WDS J06230+2231 along with UCAC2 39641417 (also designated WDS J06230+2231BC), itself a binary pair.