Applicability of lunar calendar

The length of the calendar month in the lunar calendar is strictly in accordance with the first month of the lunar calendar. 30 days in the first lunar month and 29 days in the second lunar month. The first lunar month and the second lunar month complement each other, making the average length of calendar months close to the first lunar month. For this reason, the first and fifteenth days of the lunar calendar correspond to solar and lunar eclipses, but the lunar calendar can explain natural phenomena.

Because the lunar calendar itself is of little significance to agricultural production, the 24 solar terms of the lunar calendar are a set of calculation calendars for agricultural production based on astronomical calculations in ancient times. However, the 24 solar terms are only applicable to most parts of China, covering some affiliated countries in ancient China. For foreign countries, it also has a similar law of solar terms, which has a certain impact on climate and geography.

Here are some materials to show you.

Explain an astronomical common sense

The seasons of solar and lunar eclipses. The eclipse must happen in the new moon, which is the first day of the lunar calendar. At this time, the moon is located between the earth and the sun, but because the orbit of the sun (ecliptic) and the orbit of the moon (ecliptic) form an angle of 5.9, there is not always an eclipse, but when the eclipse occurs, the sun and the moon must be near the "yellow-white intersection" (rising intersection or falling intersection).

The occurrence of the solar eclipse must be that the new moon and the full moon appear in a certain boundary where the yellow and white intersect, and this boundary is called "food limit". The calculation shows that for the solar eclipse, if the new moon is within about 18 degrees near the intersection of the ecliptic and the ecliptic, the solar eclipse may occur; If the new moon is within about 16 degrees near the intersection of the ecliptic and the white road, there must be a solar eclipse.

For an eclipse, if the full moon is within 12 degrees near the intersection of the ecliptic and the ecliptic, an eclipse may occur; If the full moon is within about 10 degrees near the intersection of the ecliptic and the ecliptic, there must be an eclipse.

Because there are two intersections between the ecliptic and the ecliptic, and the distance between the two intersections is 180 degrees, there may be two eclipses a year, both of which are called "food seasons" and are separated by half a year.

Lunar calendar: /view/ 15 163.html? wtp=tt

Twenty-four solar terms: /view/88 1937.htm