18 What's the date of the sixth day of the eighth lunar month?
The Gregorian calendar is customized based on the time that the earth revolves around the sun for one year, ***365 days, 5 hours, 48 minutes and 46 seconds. The average year is only an integer of 365 days, not a mantissa; A year is divided into 12 months, big month 3 1 day, small month 30 days, and February only has 28 days. The mantissa of four years accumulated to about *** 1 day, and it was added to February of the fourth year. This year is called leap year, so February in leap year has 29 days.
The lunar calendar orders a full moon for one month, ***29 and a half days. For the convenience of calculation, the big moon is customized for 30 days and the small moon is customized for 29 days. In 12 months of a year, large and small months are generally arranged alternately. The lunar calendar has only about 354 days a year. Generally speaking, there is no difference between normal years and stable years.
Extended data:
lunisolar calendar
Strictly speaking, the traditional calendar in our country should not be called lunar calendar, it is a lunar calendar. Now it is called "Lunar Calendar", which is the result of the so-called "four old" during the Cultural Revolution. In fact, this name is also very inappropriate. Its seasonal date can wander for as long as a month, which is not very suitable for agricultural production. To be exact, it should be called "Han Li".
(This title is based on the rules of the Han Calendar put forward by Emperor Wu of the Han Dynasty, and it was called "Han Calendar" in the Imperial System of Emperor Kangxi of the Qing Dynasty. This calendar has been called "Han Calendar" since ancient times).
The "Han Calendar" adopts the method of setting leap month and 24 solar terms, so that the average length of the calendar year is equal to the tropic year, so there is an element of the solar calendar. From this perspective, the Han calendar has its advantages. It is one of the scientific astronomical calendars in the world, which well coordinates the cycles of the sun and the moon and realizes the integration of yin and yang.
Baidu encyclopedia-lunar calendar