Sigma Canis Majoris

σ Canis Majoris
Location of σ Canis Majoris (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Canis Major
Right ascension 07h 01m 43.14779s
Declination −27° 56 05.3898
Apparent magnitude (V) 3.43 - 3.51
Characteristics
Spectral type K5 Ib
U−B color index +1.88
B−V color index +1.73
Variable type LC
Astrometry
Radial velocity (Rv)+22.11 km/s
Proper motion (μ) RA: −3.047 mas/yr
Dec.: +4.08 mas/yr
Parallax (π)2.5085±0.1590 mas
Distance1290+76
−80
 ly
(395.6+23.2
−24.4
 pc)
Absolute magnitude (MV)−5.14
Details
Mass5.61+0.51
−0.49
, 8.4±1.0, 9.1±2.0 M
Radius297 R
Luminosity15,800 L
Surface gravity (log g)0.32 cgs
Temperature3792±125 K
Metallicity [Fe/H]+0.16 dex
Age83.2 Myr
Other designations
Unurgunite, Nganurganity, 22 Canis Majoris, ADS 5719, CD−27°3544, FK5 1183, HD 52877, HIP 33856, HR 2646, SAO 172797
Database references
SIMBADdata

Sigma Canis Majoris (σ Canis Majoris, abbreviated Sigma CMa, σ CMa), also named Unurgunite /ˌʌnərˈɡʌnt/ or Nganurganity [ˈŋanuɾˌɡ̊aniɟ̊], is a variable star in the southern constellation of Canis Major. It is approximately 1,290 light-years (400 parsecs) from the Sun and has an average apparent visual magnitude of +3.41.