Why is there a leap year in September this year?

The current lunar calendar method is "seven leaps in nineteen years". Every two to three years, one month must be added, and the added month is called leap month. Therefore, the lunar leap year has 13 months.

So, how is the leap month determined? Among the 24 solar terms in the China lunar calendar, odd numbers are "solar terms" and even numbers are "neutral". "Solar term" and "neutral gas" appear alternately, each 15 days.

According to the regulations, every ordinary lunar month has solar terms, and the atmosphere is neutral. Any month with only solar terms and no neutral atmosphere is designated as a "leap month", which is exactly the case in September of the Year of the Horse. There is only the "beginning of winter" solar term on September 15, and "Light Snow" falls on the first day of next month. Because the year of the horse has a leap in September, the year of the horse is 384 days.

It is understood that because the earth is located at the perihelion and runs at different speeds, it is very unlikely to set up a leap month in winter, and there are more leap months in the third, fourth, fifth, sixth and July of the lunar calendar.

Looking through the calendar, we can see that the next lunar year with leap month will appear in 20 17, which is "leap June", and if we want to meet "leap September" again, we need to wait until 2 109.