How did the ancients get the orbit of the sun through constellations?

The ecliptic is a term in astronomy, which refers to the trajectory of the sun's apparent motion among stars, that is, the circular route between celestial bodies and stars seen by people on the earth when the earth revolves around the sun once a year. The ecliptic circle is 360 degrees. People divide it into 12 equal parts, each of which is 30 degrees, to indicate the apparent position of the sun. Take spring as the starting point and calculate its degree to the east. It should be pointed out that when the apparent position of the sun on the ecliptic is different from the real position of the earth on the orbit of revolution by 180 degrees, that is, when the apparent position of the sun is in the winter solstice, the real position of the earth is in the summer solstice. And so on. In ancient times, people quoted "auspicious days on the ecliptic". In the old Gregorian calendar, the words 12 were marked at the bottom of each date, and the days corresponding to the words12 were auspicious days of the zodiac, which were associated with the words12. Based on this, we can decide what to do and what not to do.

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