Chinese astrology is the Chinese calendar, particularly its 12 annual cycles of animals, known as the Chinese zodiac. This system of divination is derived from the main features of the system: the five elements (12 horoscopes designating the 12 zodiacal animals) of Chinese thought, calendar cycles based on astronomy, and ancient Chinese religion. The ancient Chinese astronomers assigned to each of the five major planets of the five Chinese elements: Venus, the metal (gold); Jupiter, wood; Mercury, water; Mars and Saturn fire, earth.