Alhena - γ Geminorum (gamma Geminorum)
Alhena, also designated as γ Geminorum (gamma Geminorum), is a multiple hypergiant star in the constellation of Gemini.
Alhena visual magnitude is 1.93, making it the 42th brightest star in the sky. Thanks to its high brightness, Alhena is clearly visible when observed from locations with dark skyes, and should be also quite easily visible from light polluted areas.
The table below summarizes the key facts about Alhena:
Celestial coordinates and finder chart of Alhena
Alhena is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year. Celestial coordinates for the J2000 equinox as well as galactic coordinates of Alhena are provided in the following table:
The simplified sky map below shows the position of Alhena in the sky:
Visibility of Alhena from your location
Digitized Sky Survey image of Alhena
The image below is a photograph of Alhena 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 Alhena is 0.042 arcsec per year in Right Ascension and -0.042 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.
Distance of Alhena from the Sun and relative movement
Alhena is distant 104.76 light years from the Sun and it is moving towards the Sun at the speed of 13 kilometers per second.
Spectral properties of Alhena
Alhena belongs to spectral class A0 and has a luminosity class of IV corresponding to a hypergiant star.
The red dot in the diagram below shows where Alhena is situated in the Hertzsprung–Russell diagram.
Alhena star system properties
Alhena 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 Alhena double sysyem: