Why are there twelve constellations?

The constellation originated in Babylon, one of the four ancient civilizations.

Zodiac: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces.

In order to facilitate research, people divide the starry sky into several regions, which are called constellations. China divided the sky into three walls and twenty-eight nights. Historical records and official records are quite detailed. Sanyuan revolves around the north celestial pole.

Three areas, namely Ziwei Garden, Taiwei Garden and Tianshi Garden. 28 boarding houses are located in 28 areas near the ecliptic and the white road, namely, 7 boarding houses in the east, 7 boarding houses in the south, 7 boarding houses in the west and 7 boarding houses in the north.

Now the constellation we often say is "Zodiac 12 Palace".