The origin of 12 constellation, the time when the sun passes through a certain constellation, and people born at this time belong to this constellation.

The twelve constellations, or zodiac signs, are astrologically described areas where the sun passes through the zodiac on the celestial sphere, including Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces. Ophiuchus also passes through the zodiac, but it does not belong to the zodiac used in astrology. In astrology, the zodiac is defined as 1928. After the international astronomical union standardized the constellation boundary, there are 13 constellations on the zodiac.

Because of precession, the zodiac in 2 1 century no longer conforms to astrology.