What are the zodiac signs?

The representation of the ecliptic is similar to the representation of the equator of the earth. The equator of the earth is expressed in longitude, which is east-west, starting from Greenwich Observatory in Britain, with longitude of 0, from 0 to 180, and east longitude. West longitude, from 0 to180; East-west longitude 180 coincides. The east-west direction is represented by the "ecliptic", the circle from east to west is 0 to 360, starting from vernal equinox, the intersection of the ecliptic and the celestial equator, and the ecliptic is 0. The ecliptic circle around the celestial sphere is 360, but 12 zodiac signs are not all generally long in the east-west direction, and some are long and some are short. The longest is Virgo, which is 44 on the ecliptic, which is almost1/8 of the total length of the ecliptic; The shortest is Cancer, only 20. As I said before, the sun runs on the ecliptic and moves less than 1 from west to east every day. These constellations on the ecliptic are long or short, and the time required for the sun to pass through each constellation is long or short. This is inconvenient to calculate the date according to the position of the sun. This introduces the concept of the zodiac. It is generally believed that in ancient Babylon and Greece, astronomers decided to divide the ecliptic into 12 segments, each of which is 30, in order to show the movement and position of the sun on the ecliptic. After long-term practice, this means that the sun moves and stays in a palace every month. In this way, in the 12 months of a year, the sun passes through the 12 house in turn, with a total of 360 degrees, that is, a circle on Sunday, and the next year starts from the vernal equinox and repeats itself. 12 What's the name of "Sun Palace"? Naturally, we should refer to the name of the original 12 zodiac. We put the zodiac, together with their starting and ending degrees, the date when the sun enters the palace every year (because the solar calendar has 365 days and 366 days, and the sun changes about 1 day every day when it enters the palace), and the solar terms when it enters the palace. It is introduced in tabular form as follows: the name of the zodiac, longitude of the yellow sun, date of solar terms, remarks about Aries 0 ~ 30 March 2 1 the first point of Aries at the vernal equinox 30 ~ 20 April 60, Grain Rain twins 60 ~ 2 May 901Xiaoman Cancer Palace 90 ~ 65438+. During the summer solstice, the first spots in Cancer Palace are Lion Palace120 ~150 July 23rd, Summer Palace150 ~180 August 23rd, Libra Palace 180 ~ 2 10 9. 65438+1early frost Sagittarius 240 ~ 270 65438+1October 22 Xiaoxue Capricorn Palace 270 ~ 300 65438+February 22 winter solstice Capricorn Palace 300 ~ 330 065438+/kloc-