1933 is a leap in May?

Why is there a leap month in the lunar calendar?

We often say that the Gregorian calendar takes the earth's revolution around the sun as 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 revolves 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 calendar of yin and yang. 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 a big month, 29 days in a small month, and only 354 or 355 days in a year. In this way, the year of the lunar calendar is about 1 1 day or less1day than the Gregorian calendar year that we often use. Therefore, in order to keep up with the changes of the four seasons, people will add a month after a certain period of time and call this month a leap month.

Since the western Gregorian calendar was used, the traditional calendars in China have been called old calendars or traditional calendars. Later, the western calendar was called the solar calendar, while 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, it may happen that some months have a solar term at the end of the month and there is only one solar term next month. According to the lunar calendar, a leap month is arranged after this month. For example, on April 28th of the 1982 lunar calendar, there is only one solar term next month, and there will be a summer solstice next month. Therefore, arrange a leap month after April, which is called leap April.

Leap months occur every few years.

As the saying goes, "leap every three years, leap every five years", which 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.