σ Geminorum (sigma Geminorum)
σ Geminorum is a variable and double giant star in the constellation of Gemini.
σ Geminorum visual magnitude is 4.28. Because of its moderate brightness, σ Geminorum should be easily visible from locations with dark skyes, while it can be barely visible, or not visible at all, from skyes affected by light pollution.
The table below summarizes the key facts about σ Geminorum:
Celestial coordinates and finder chart of σ Geminorum
σ Geminorum is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of σ Geminorum are provided in the following table:
The simplified sky map below shows the position of σ Geminorum in the sky:
Visibility of σ Geminorum from your location
Digitized Sky Survey image of σ Geminorum
The image below is a photograph of σ Geminorum from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of σ Geminorum is 0.065 arcsec per year in Right Ascension and -0.232 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.
Distance of σ Geminorum from the Sun and relative movement
σ Geminorum is distant 122.19 light years from the Sun and it is moving far from the Sun at the speed of 46 kilometers per second.
Spectral properties of σ Geminorum
σ Geminorum belongs to spectral class K1 and has a luminosity class of III corresponding to a giant star.
The red dot in the diagram below shows where σ Geminorum is situated in the Hertzsprung–Russell diagram.
σ Geminorum star system properties
σ Geminorum is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the σ Geminorum double sysyem: