What are abortion and big moon?
The size of the months in the solar calendar is regular. Before July, a single month was a big month and two months was a small month. After August, two months are big months and a single month is small, so 1 month, March, May, July, August,1month,1February are big months, and April, June, September,1/kloc.
Extended data lunar calendar
The lunar calendar is not a simple lunar calendar, but a combination of yin and yang. Take the change period of the moon phase as the length of the month, add the "24 solar terms" component of the trunk calendar, and refer to the length of the tropical year of the sun as the year. By setting leap months, the average calendar year can adapt to the tropic year.
Lunar calendar is a calendar based on China calendar (lunar calendar) and integrated with solar calendar. Therefore, strictly speaking, the lunar calendar in China should not be called the lunar calendar, but the combined calendar of yin and yang.
The lunar calendar is based on the lunar calendar (China calendar), because the lunar calendar is based on the change of the moon phase, regardless of the movement of the earth around the sun, so the changes of the four seasons in the summer calendar have no fixed time and cannot reflect the changes of seasons; However, the calendar can reflect the tidal phenomenon and is a guide for guiding maritime activities in ancient times.
Unlike the fixed solar year of 365 days or 366 days, the solar year sometimes differs from the lunar year by one month. In order to coordinate the number of days between the first month of the lunar calendar and the tropic year, the "leap method" is adopted to adjust the total number of days between the lunar calendar and the tropic year.
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