Observing the Constellation Gemini
Finding Stars, Nebulae and More in the Twins
Get the facts on Gemini the Twins: learn its stars, clusters, mythology, and more!
Gemini the Twins is one of the twelve zodiac constellations. It is easy to see the picture of two stick figures representing the twins, Castor and Pollux. In Greek myth, the twins were sons of Leda and Zeus. The heads of the twins are represented by stars that are named for the mythological characters. Pollux is the brighter of the two stars and the one on the left. Pollux is a yellow-orange giant star with a magnitude of 1.15. Castor is a hot white star system consisting of four members. Its magnitude is 1.58.
One Messier object resides in Gemini, the star cluster M35. M35 lies near Castor's left foot. The 5th magnitude cluster lies about 2,800 light-years from Earth. Just below is another fainter cluster, IC 2157 at 8th magnitude. Pollux's outside knee points to another 8th magnitude cluster, NGC 2395.
Two semi-bright nebulae lie in Gemini. NGC 2392 has the nickname of the Clown Face Nebula or the Eskimo Nebula. It lies to the outside of Pollux's hip star and shines at magnitude 10. A six-inch scope might allow observers to catch another planetary nebula in Gemini: NGC 2371. The 13th magnitude nebula lies between the shoulders of the twins.
Galaxies in Gemini are mostly very faint and very difficult for the casual observer to find.
