Are there two Mid-Autumn Festival and two Chinese Valentine's Day in July this year?
Why does the year of the dog "leap in July"
At the beginning of the new year, when people look through the new calendar, they will find that the lunar July next year (Year of the Dog) is not followed by August, but "leap July". Why will there be "leap July" next year? To understand the truth, we should start with the calendar.
Calendar can be divided into solar calendar, lunar calendar and yin-yang calendar. The solar calendar takes the annual apparent movement period of the sun (i.e. tropic year, equal to 365.2422 days) as a year, which is divided into 12 months, and has nothing to do with the movement of the moon. According to the grim date, we can know the changes of the four seasons from winter to summer, but it can't show the complete and short period of the moon, which is inconvenient for those who need to know the tidal changes according to the moon phases.
In the lunar calendar, the full moon (that is, the new moon, equal to 29.5306 days) is a month, and the product of 12 months is one year. The annual apparent motion law of the sun is completely ignored, so the date of the lunar calendar can't show the warmth and coldness of the four seasons. This calendar has no practical value, and now it has been abandoned except Islam.
The lunar calendar is the China lunar calendar, which emphasizes the length of the solar calendar and avoids the shortness of the lunar calendar. The month of the lunar calendar is the month and the year of the solar calendar is the year, that is, the moon is the month and the tropic year is the average length of a year. Therefore, the lunar calendar is a solar calendar with lunar elements and a lunar calendar with solar elements. According to the date of the lunar calendar, we can not only know the ebb and flow of tides, but also basically grasp the changes of seasons. The lunar calendar is an original creation of our country, which shines with the wisdom of our ancestors.
Because the tropic year is inseparable from the first month of the lunar calendar, for convenience, the lunar calendar stipulates that the first month is 30 days and the second month is 29 days, and a year is 12 months * * 354 or 355 days, which is about 1 1 day less than the tropic year of 365.422 days, and the total of four years is less than one month. Over time, there will be a strange phenomenon of time sequence and time disorder. For example, the Spring Festival in 2002 is on February 12 in the solar calendar, which is a cold winter season. The Spring Festival in 2003 is on February 1 day in the solar calendar, which is earlier than the previous year 1 1 day. If no measures are taken, it will be promoted year by year, adding up to 16, and the Spring Festival will be celebrated in midsummer. Farming activities are also irregular-sometimes wheat is planted in 10, and sometimes wheat is planted in September ... which is naturally inappropriate. In order to solve this problem, the method of adding "leap month" is adopted.
As early as 600 BC, our ancestors began to adopt the "7-leap method of 19", that is, in the lunar year of 19, it was stipulated that 12 normal years, each year 12 months; In the other seven years, 1 month will be added every year to become 13 months. This added month is called "leap month". Thus, the total number of days in 19 lunar year (12× 12 months +7× 13 months) ×29.5306 days =6939.69 10 days,10 days.
As for how to arrange the leap month, it is completely artificial. Before the Qin dynasty, the leap month was placed at the end of a year, called "March"; The leap month in the early Han Dynasty was placed after September, which was called "the last September". In the first year of Emperor Wu of the Han Dynasty, a leap month was inserted every month. The current lunar calendar stipulates that a month without "neutral qi" is a leap month.
What is "neutral gas"? As we all know, ancient astronomers called the 24 solar terms singular and even neutral according to the order of beginning of spring, rain and sting. There are 12 solar terms and 12 neutral qi in a year. It is stipulated that 12 months of the lunar calendar should be marked with 12 neutral qi, that is, each month should contain a specific neutral qi. For example, the first month must include rain, and February must include the vernal equinox ..., otherwise it cannot be called the first month and February. Any month without neutral gas is designated as leap month.
Why is there no neutral gas for a month? Because the 24 solar terms are determined according to the solar calendar, its date is basically fixed in the solar calendar. The average number of days between solar terms or neutral atmosphere is 365.2422 days12 months =30.4368 days, while the average number of days in a lunar month is 29.5306 days, a difference of about one day. Therefore, according to the solar calendar, the date of qi in the lunar calendar will be delayed by one day every month. Put it off until the end of the month, and there will be only solar terms next month, and there will be no gas.
As can be seen from the attached table, there are only solar terms and white dew in the month after July, and the summer heat in beginning of autumn has dropped to another month, so there will be another month without gas after July. Therefore, the lifeless month after July is named "leap July" after July, which is the reason for this year's "leap July".
It can be seen that leap month and leap month are completely artificial regulations, which have nothing to do with the world and good or bad luck.