These days, when carefully reading the calendar, you will find that the dates of November and the 10th month of the lunar calendar perfectly overlap: November 1, the Gregorian calendar is the first day of the tenth month of the lunar calendar, and November 30, the Gregorian calendar is the 30th day of the 10th month of the lunar calendar. What's going on? Listen to what the astronomical science experts say.
Yang Jing, a member of the Chinese Astronomical Society and director of the Tianjin Astronomical Society, said that this is not a typographical error, but a coincidence caused by the arrangement of my country's calendar.
She introduced that as the current calendar commonly used in the world, the Gregorian calendar is based on the movement cycle of the earth's orbit around the sun for one week, that is, a return year. The length of a return year is 365.2422 days Source: 2yn.hgko.sc.cn, 12 months a year. Since the regression year is not an integer, the Gregorian calendar stipulates that one day will be added every 4 years, and this year is called the leap year of the Gregorian calendar. Any leap year that can be divided by 4 is 366 days, and the average year that cannot be divided is 365 days, and the day that increases is arranged in February. It is a leap year that can be divided by 400 in integer centuries, otherwise it is a normal year, so there are 97 leap years in every 400 years.
The lunar calendar is a traditional calendar in my country. It is formulated based on the moon's cycle orbiting the earth's cycle and the earth's cycle orbiting the sun. It is a kind of yin and yang calendar. The lunar month is defined as the moon's profits, losses, and the lunar month is defined as the "singlength and new" cycle. The average length of a singlength and new year cycle is 29.5306 days. Since the number of days in the lunar month is also represented by integers, sometimes it is the 29th day of the small month. Source: z4e.hgko.sc.cn, and sometimes it is the 30th day of the big month.
There are leap years in the Gregorian calendar, and there are also leap years in the lunar calendar. The method is "seven leap years in the 19th year". On average, one leap month is arranged every two or three years. The lunar year with leap months includes 13 months, with an age of about 384 days, and the year without leap months is 354 days or 355 days.
Yang Jing pointed out that compared with the comparison, it can be found that the length of the Gregorian year is almost unchanged, while the length of the lunar year changes greatly, which makes the lunar calendar and Gregorian dates in the year not relatively fixed. The corresponding Gregorian dates on the first day of the lunar calendar are: 8wt.hgko.sc.cn, which can float for about 30 days. As time goes by, the source of a certain year is: 5zx.hgko.sc.cn. The first day of a certain lunar month will coincide with the 1st day of the adjacent lunar month.
Since the length of the 19 lunar calendar years is almost equal to the length of the 19 lunar calendar years, the calendar date and the lunar calendar date overlap or almost coincide every 19 years. The next time the lunar month happens perfectly coincides with the date of the adjacent Gregorian month is in June 2030 (the fifth month of the lunar calendar), while the lunar calendar month repeats with the 10th month of the Gregorian month happens in 2062.
Yang Jing said that the lunar calendar is based on natural astronomical phenomena and changes within certain laws. Although sometimes it is a bit "brain-burning" source when it comes to "conversion": awc.hgko.sc.cn, this is also the charm of traditional Chinese calendars.