Traditional Culture Encyclopedia - The 24 Solar Terms - How many days does one of the 24 solar terms last?

How many days does one of the 24 solar terms last?

15 days

Solar terms come from the earth's revolution around the sun, so they don't correspond to the traditional lunar calendar in China, but basically correspond to the Gregorian calendar. Each solar term is a fixed earth motion 15 (360 divided by 12), but the time is not fixed (the trajectory is not a circle but an ellipse, and the angular velocity and linear velocity are not fixed values). So each solar term is generally 15 days.

Extended data:

Twenty-four solar terms originated in the Yellow River Basin.

As early as the Spring and Autumn Period, four solar terms were set, namely, mid-spring, mid-summer, mid-autumn and mid-winter. After continuous improvement and perfection, by the Qin and Han Dynasties, the 24 solar terms had been completely established.

In BC 104, the taichu calendar written by Deng Ping officially set 24 solar terms in the calendar, and defined the astronomical position of the 24 solar terms.

Twenty-four solar terms reflect the apparent movement of the sun in one year, so the dates of solar terms are basically fixed in the current Gregorian calendar, with the first half of the year being 6 days and 2 1, and the second half being 8 days and 23 days, with a difference of 1 ~ 2 days.