B-type star · blue-white star

Alhena

Alhena is a blue-white star in the constellation Gemini 109 ly from Earth. Its surface is about 10,113 K, about 1.8 times the Sun's surface temperature, and it shines at 165× the Sun's brightness. At magnitude 1.9 it is bright enough to see with the naked eye; the light you see left it 109 years ago.

109 lybrightness mag 1.93A0IV

Also catalogued as Gamma Gem · HR 2421 · HD 47105 · HIP 31681

10,113 K
temperature
1.93
apparent magnitude
165× ☉
luminosity vs Sun
A0IV
spectral type
Distance & comparison with our Sun
109 years
at light speed from Earth
1.75×
as hot as the Sun
165×
the Sun's light output
-0.70
absolute magnitude
Explore from here · roam the neighborhood
AlhenaB-type
Sky regionGeminithis direction
StarLusitania12 ly
StarHR 243916 ly
StarLambda Gem20 ly
StarPolluxstar
StarCastor Bstar
Nearest stars
Bright stars in Gemini
Can you see it tonight?
VISIBLE TO THE NAKED EYE
Brightness mag 1.9To see it no equipment neededLook toward Gemini

Star data from the HYG database v4.2 (Astronexus, CC BY-SA 4.0). Temperature and colour computed by gravityfinder from the B-V colour index; the illustration is generated from that temperature, not a photograph.