Zodiac constellations can be traced even further back, to Bronze Age (First Babylonian dynasty) sources, including Gemini "The Twins", from MAŠ.TAB.BA.GAL.GAL "The Great Twins", and Cancer "The Crab", from AL.LUL "The Crayfish", among others. Around the end of the 5th century BC, Babylonian astronomers divided the ecliptic into twelve equal "signs", by analogy to twelve schematic months of thirty days each. Each sign contained thirty degrees of celestial longitude, thus creating the first known celestial coordinate system. Unlike modern astronomers, who place the beginning of the sign of Aries at the place of the Sun at the vernal equinox; Babylonian astronomers
Chinese zodiac the elements is also linked to a season (see above), and the element that shares a season with a sign is known as that sign's "fixed element". In other words, that element is believed to impart some of its characteristics to the sign concerned. The fixed element of each sign applies also to the year and hour signs, and not just the monthly sign. The fixed element is separate from the cycle of elements which interact with the signs in the 60-year cycle. Four pillars calculator can determine the zodiac animal of the day. Chinese animal signs rule over days