Which month is the double leap month in 2020?

Why is there a leap month in the lunar calendar?

In the Gregorian calendar, we often say that the earth revolves around the sun once a year, and the time is 365 days, 5 hours, 48 minutes and 46 seconds.

On the other hand, in the lunar calendar, the moon goes around the earth for one month for 29 and a half days.

The lunar calendar is mainly used by people in East Asia, and it is a traditional lunar calendar. According to legend, it was created in the ancient Yellow Emperor era or Xia Dynasty, and the lunar calendar is also called the Yellow Calendar and Li Xia.

There are 30 days in the big moon, 29 days in the small moon, and only 354 or 355 days in a year. In this way, the year of the lunar calendar is about less than that of the Gregorian calendar 1 1 day or less1day. Therefore, in order to keep up with the changes of the four seasons, people will add a month after a certain period of time, which is called leap month.

Since the western Gregorian calendar was used, the traditional calendar in China has been called the old calendar or the traditional calendar. Later, the western calendar was called the solar calendar, and the old calendar was called the lunar calendar.

The determination of leap month is actually mainly related to the 24 solar terms. The date of the twenty-four solar terms of the lunar calendar is postponed month by month. In this way, there may be a solar term at the end of some months and only one solar term next month. The lunar calendar stipulates that a leap month will be arranged after this month. For example, 1982 on April 28th of the lunar calendar, there is only one solar term in the following month, and there will be a summer solstice in the following month. Therefore, arrange a leap month after April, which is called leap April.

Leap months occur every few years.

As the saying goes, "leap in three years, leap in five years" means that there will be a leap month every two or three years in the Lunar New Year. There is a summary of "seven leaps in nineteen years" among the people.