In what year does leap month occur?

Run once every three years, twice every five years and seven times in nineteen years.

Leaping month is a way of calendar leap. In Asia (especially in China), leap month refers to the month added every leap year in the Han calendar (also known as the lunar calendar) (in order to coordinate the contradiction between the tropic of Capricorn and the Han calendar;

In order to prevent the lunar calendar of the Han Dynasty from being out of touch with the tropic year and the four seasons, 1 leap is set every two to three years. In ancient times, 19 was used as leap week, and there were 7 leaps. By the time of Linde calendar in Tang Dynasty, the fixed leap week was abolished, and a month without season was regarded as leap, so it was leap time.

In our traditional calendar, the time when the earth rotates once is set as one day, and the time when the sun and the moon appear on the earth is set as the beginning of a month. According to the cycle of the moon, it is set as one month. Although the length of each year may not be equal, if we average the length of each year, we can find that a year is about the length of the tropic of cancer.

Such a calendar can not only ensure that the full moon day is in the middle of each month, but also ensure that the changes of cold and warm seasons can be seen by month. The key to reconciling Yin and Yang lies in the setting of "leap moon". Leap month enables people to determine the starting point of the one-year cycle and adjust the length of a year on the calendar to make it as close as possible to the tropic year.

Extended data:

Reasons for leap month:

There are three calendars in the world: one is the solar calendar, which means that the time for the earth to make a circle around the sun is one year, and the number of months and days in a year can be specified artificially; One is the lunar calendar, in which the time for the moon to circle the earth is one month, and only a few months in a year can be designated artificially;

The third is the lunar calendar, that is, the average time for the moon to go around the earth is January, but by setting leap months, the average number of days in a year is equal to the average time for the earth to go around the sun, such as the Chinese calendar and Tibetan calendar.

So China's Han calendar is not a lunar calendar, but a yin-yang calendar. The lunar calendar and the solar calendar in the Han calendar have their own uses. The lunar calendar can indicate the moon's profit and loss, and can also predict the tides.

Lunar calendar is more useful. Twenty-four solar terms are a great invention in ancient China. It shows the position of the earth in orbit, reflects the annual apparent movement of the sun, and is most suitable for guiding agricultural activities. Therefore, the traditional lunar calendar in China is called the lunar calendar. Therefore, the lunar calendar is different from the lunar calendar, and it is not appropriate to call the lunar calendar the lunar calendar.

The sun and the moon are calendars that people hang in the sky. Year after year, the earth revolves around the sun, and everything on the earth lives and multiplies in the cycle of the sun and the moon.

Baidu encyclopedia-leap month

People's Network-Yueyue: the wisdom of the ancients to reconcile Yin and Yang