The time of one volt, two volts and three volts in 2022

There are 40 days in dog days in 2022, namely, dog days 10 days, dog days 20 days, dog days 10 days. But in some years, the dog days will last for 30 days. Why are the dog days different every year? In fact, the reason for determining the number of dog days is determined by "Geng Day". When there are five Geng days in the second volt, it is 20 days.

The sign of entering the dog days is based on the third Geng day after the summer solstice solar term, that is, from the day of the summer solstice solar term to the first day when the third Geng day is full, the fourth Geng day is the beginning of the dog days, and the first Geng day after the autumn solar term begins is full, so there is also a saying that "beginning of autumn will be full after the solar term".

Gengri is the name used by ancestors to time. "Geng" belongs to 10. It is combined with 12 to record the date, which produces the "Geng Day". In ancient times, 60 days was regarded as a cycle, and six of them had the word "Geng", such as Gengzi Day and Gengxuri. Every 65,438+00 days is a Geng Day, which is why it is mostly 65,438+00 days in dog days. The dog days in 2022 are 40 days, because July 26th is two days and August 7th is the solar term in beginning of autumn. As mentioned earlier, 10 is the dog days after the solar term in beginning of autumn, and August 15 is another Geng day, that is, August 15 is the first day of the dog days.