When watching the sky with binoculars, Gemini is one of the most interesting constellations to observe. Gemini is an open cluster being named after twins Kastor and Polydeuk in Greek mythology. Brightest stars of Gemini are Castor (alpha Geminorum) and Pollux (beta Geminorum). There are also an open cluster M35 and cepheid variable stars zeta, Geminorum as well as other interesting targets to observe. This article helps you to locate Gemini constellation and its stars Castor and Pollux.

Gemini can be seen well right now here in northern hemisphere. It is located high in the sky and it is in meridian in the middle of February 10 pm EET. In order to locate Gemini, you should be able to find Orion constellation first. If you cannot locate Orion yet, read my article of finding Orion and M42.

As soon as you have located Orion in southern sky in northern hemisphere, start looking for Gemini as shown in the figure left. Gemini is located in North-West from Orion and it is the neighbour constellation of Orion. Another way to find Gemini is to locate first Big Dipper. Drawing a line from Big Dipper’s four stars (as shown in the figure left) brings you directly to Gemini’s bright star Pollux. Now that you know how to locate Gemini and Pollux, you can easily find also Castor which is on right side of Pollux, as shown in the figure.

Pollux is a red giant and the brightest star in Gemini. It is located in 36 light years away from Earth. Castor is the second brightest star in constellation Gemini, and it is located in 51.6 light years away from us. In fact, Castor is not just one star, but a combination of six stars. When compared to the Sun, the brightness of all stars in Castor is 52.4 times of the brightness of the Sun.