Why is Gemini called Gemini in the night sky?

Because Gemini is to commemorate the two brothers in myth and legend.

In ancient western mythology, Castel, the elder brother of Gemini, was the son of Sparta, and Procus, the younger brother, was the son of Zeus, so he was immortal. The two grew up together and had a very good relationship. After my brother Caster died, only paulus was immortal. So Procus asked Zeus to go to the grave with Castor.

Zeus then agreed that the two brothers would take turns living in heaven and hell. To commemorate the twin brothers, ancient Rome also built temples for the twin brothers-the temples of Caster and Polonius.

Introduction to Gemini

Gemini is one of the zodiac signs, with an area of 5 13.76 square degrees, accounting for 1.245% of the whole day, ranking 30th among the 88 signs in the whole day. Gemini has 47 stars brighter than 5.5, the brightest star is Beihe III, and the apparent magnitude is 1. 14. This constellation is just above the observer's head when the Gemini center passes through the upper meridian on the night of 65438+10.5 every year.

Although Gemini beta star (Beihe III) is named "beta" star, it is brighter than "alpha" star (Beihe II) from the earth. It is 33.7 light years away from the earth and its luminosity is 32 times that of the sun. It is one of the recent red giant stars and one of the brightest stars in the universe. Observed with binoculars, the orange of Beihe III is in sharp contrast with the blue of Beihe II, which is very bright. This spectacular sight can be clearly seen in most parts of our country.

Although Beihe II and Beihe III are described as "twins" of constellations, their characteristics are quite different. The former is a blue and white main sequence star, and the latter has entered the stage of red giant star. Moreover, Beihe II and Beihe III are still moving in two opposite directions.