Formula of lunar calendar size and month

The lunar formula is big in January, flat in February, big in March, small in April, big in May, small in June, big in July, big in August, small in September, big in October, small in November and big in December.

If you can't remember, hold your fist with the back of your hand up. From the number of bones protruding near the back of your index finger, it can be said that the big moon is yin and the small moon is yang, and the year is divided into yin and yang in order of size. If there is a leap month, there is one more month, and a year is thirteen months.

Between adjacent hexagrams in leap years, the year and month are determined according to the festival. When there is a leap month, it is represented by Yin and Yang hexagrams according to the size of the leap month, and marked on the left side between the two months before and after the leap month. Just like divination, you can tell at a glance whether a leap month is a big one or a small one.

Twenty-four solar terms of the lunar calendar:

Twenty-four solar terms are special festivals in China calendar to express the change of natural rhythm and establish December, which can accurately reflect the change of natural rhythm and contain a long cultural connotation and historical accumulation. Twenty-four solar terms were originally formulated according to the changes of the stars. The Big Dipper rotates circularly and bucket handle rotates clockwise once, which is called one year old.

At present, the establishment of the 24 solar terms is based on the annual apparent motion of the sun, that is, the longitude of the sun. Although the two methods are different, the reason why the stars change is that the earth revolves around the sun, so the time of the two festivals is basically the same. In the historical development, the 24 solar terms have been incorporated into the lunar calendar and become an important part of the lunar calendar.

The months of the lunar calendar basically correspond to the twelve seasons, and the twelve solar terms can appear in the second half of last month and the first half of this month. Twenty-four solar terms are an important part of the long history and culture of the Chinese nation, which condenses the historical and cultural essence of Chinese civilization.