How is the leap year calculated in the lunar calendar, and is it the same as the national calendar?

Leap years in the lunar calendar are characterized by one leap month every three years, which adds up to a total of five leap months every nineteen years.

A month is added every three years, and this is the leap month in the lunar calendar. A year with a leap month is also called a leap year, so the folk have "three years, two leap, three years, two non-leap" said.

The traditional lunar calendar adopted by China for thousands of years is a yin and yang calendar, which takes into account both the solar return year, which is directly related to the sun, and the lunar month, which is related to the change of the moon's phase.

A lunar month is about 29.5 days, and the lunar calendar generally has 12 lunar months in a year***354 or 355 days, about 11 days less than the solar return year.

In order to harmonize the lunar year with the solar year, the ancients arranged for "nineteen years and seven intercalary", i.e., every two or three years in the lunar year will arrange a leap month. In this way, there is a difference between a leap year and a flat year.

Unlike the solar year, which is fixed at 365 or 366 days, a leap year in the lunar calendar has about 384 days because of the extra leap month, while a leap year in the lunar calendar usually has 354 or 355 days.

Extended information:

The creation of the lunar month

The lunar month is the average period of the Moon's revolution around the Earth relative to the Sun. It is the average cycle of the moon's phases of waxing and waning. Taking the time interval from Solstice to the next Solstice or from Watch to the next Watch as its length, it averages 29.53059 days.

As the relative positions of the sun, moon, and earth change, the moon takes on different shapes on different days, which is the change in the cycle of the moon's phases.

Since the moon is constantly revolving around the earth, changing its position from time to time, the half of its sphere facing the earth and the half of its sphere illuminated by the sun sometimes coincide completely and sometimes not, so the moon shows the change of yin and yang.

China's forefathers called a cycle of the moon as a "moon cycle", the moon is not seen at all the day called "Shuozhi", the first day of the month of the lunar calendar; the moon is the fullest day called "Wangzhi", for the lunar calendar. The day when the moon is fullest is called the "Hope Day", which is the fifteenth (or sixteenth) day of the month on the lunar calendar.

From Shuo to Wang, is the first half of the lunar month; from Wang to Shuo, is the second half of the lunar month; from Shuo to Wang to Shuo for the lunar month. A lunar month is 29 days and a half, which is actually 29 days, 12 hours, 44 minutes and 3 seconds.

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