Beginning of spring twice in many years?

It will appear every two or three years on average.

The ancients added seven leap years every 19 years in the lunar calendar, that is, seven years without beginning of spring, seven years with double beginning of spring and five years with single spring.

Beginning of spring's Time Law

5 degrees is a solar term, and 360 degrees is 24 solar terms once a year. Therefore, the date of solar terms in the solar calendar is basically fixed, and "beginning of spring" is usually on February 4th every year.

But the dates of solar terms in the summer and lunar calendars are not fixed. China's traditional calendar summer calendar is a combination of yin and yang: "Yin" means that the average length of its calendar month is 29 days in the first lunar month, and the first day of each month is the first lunar month; "Yang" refers to the Spring Festival, which is based on the tropical year and takes the first day of the first month around beginning of spring every year as the first day of the first month of the year.

The summer calendar 12 year has only 354 or 355 days on average, and the 13 year with leap months has 384 or 383 days, which can contain 25 solar terms. In this way, there will be a "beginning of spring" at the beginning and end of each year, which will become a "double spring year". There will be only 23 solar terms next year, so there will be no "beginning of spring" and it will become a "double spring year".

For example, in 2005, the year of the monkey had a leap in February, which was a "double spring year", and the year of the rooster became a "no spring year" the following year.

It can be seen that "no spring" after "double spring" is completely the result of calendar arrangement according to certain rules, and it often appears.

There is no "beginning of spring" in the whole year, and 19 will appear seven times, such as 199 1, 1994,1997,2000,2002,2005,2008.