Will April 2020 leap?

1906 (the third year of the afternoon) 1925 (the ugly year) 1944 (Shen Jianian)

1963 (year of Guimao) 1974 (year of Jiayin) 1982 (year of Renxu)

200 1 (Xinsi Year) 20 12 (Nonchen Year) 2020 (Gengzi Year)

2058 (Wuyin Year) 2069 (Ugly Year) 2077 (Ding Younian)

2088 (the year of Wushen) and 2096 (the year of Chen Bing)

Therefore, it can be seen from the above that if we want to meet leap April again after 2020, it can only be 38 years later in 2058.

Why is there a leap month in China lunar calendar?

Arrange the big moon and the small moon according to the full moon. The length of a moon is 29.5306 days, which is the cycle of the moon's profit and loss. According to the lunar calendar, there are 30 days for the big moon and 29 days for the small moon, and a year is 12 months ***354 days. The months of the lunar calendar have no seasonal significance, so twelve months constitute the Han calendar, with a length of 29. Compared with the tropical year of 365.2422 days (about 1 1 day), it is 10.88 days less and 0.9 1 day less per month (about 1 day). The difference between solar calendar year and year is 1 1 day. Only after 17 will the date of the lunar calendar be reversed in the same season. For example, a year's New Year is spent in the snow, and a new year comes after 17. Using such a calendar naturally cannot meet the needs of agricultural production. Therefore, since the Qin and Han Dynasties, the lunar calendar in China has been in parallel with the twenty-four solar terms, which are used to guide agricultural production.

If the lunar year consists of thirteen lunar months, the length is 29.5306× 13=383.8978 days, which is more than the tropic year 18 days.

If the calendar is made according to the above regulations, there will be a strange phenomenon that the weather is inconsistent with the calendar and the time order is disordered and reversed. This is the contradiction.

In order to overcome this shortcoming, our ancestors explored the method of "leap month" on the basis of astronomical observation, ensuring that the first month to March is spring, April to June is summer, July to September is autumn, and October to December is winter, and at the same time ensuring that the first year of the lunar calendar is in the late winter and early spring (all above refer to lunar month).

Therefore, in a word, the leap month appears only to correctly set up extra calendar days.