Mid-Autumn Festival seems a little naughty. Last year, the solar calendar date was September 15, and next year is September 24. This means that this year's Mid-Autumn Festival is 19 days later than last year, and next year's Mid-Autumn Festival is 10 days earlier than this year. Why are the corresponding Gregorian dates so different?
Zhao Zhi Heng, an expert in astronomy education and director of Tianjin Astronomical Society, explained that the Mid-Autumn Festival belongs to the current lunar calendar in China. According to the lunar calendar, there are 30 days for the big moon and 29 days for the small moon, and a year is 12 months ***354 days or 355 days, which is about 1 1 day less than a tropical year. After three years, it is 1 month less. In order to solve this problem, the Chinese lunar calendar stipulates that one month is added intermittently in a year for overall mediation.
The extra month is called "leap month", and the method is "19 years and 7 leap years", that is, every 19 years, 7 years is 13 months (including leap months), and other 12 years are 12 months per year. "Due to the ingenious arrangement of leap months in our calendar, the solar calendar day corresponding to the Mid-Autumn Festival is always about 1 1 day in advance or about 19 days later. Not just the Mid-Autumn Festival, but any fixed day of the lunar calendar. " Zhao Zhi Heng said, "In this century, Mid-Autumn Festival is possible. Every day is from September 7th to June 6th in the solar calendar, 10. Therefore, the earliest Mid-Autumn Festival and the latest Mid-Autumn Festival can differ by one month. "
The moon on the fifteenth is seventeen circles?
On the Mid-Autumn Festival night this year, that is,1October 4 17: 23, the moon will rise in the east. By 23: 26, the moon is the highest and brightest in the Mid-Autumn Festival, which is located in the south direction of people's sight. At this time, it is also the best time to enjoy the moon. The autumn moon will shine brightly in the sky until it sets slowly at 5: 34 the next morning.
However, according to astronomical observation data, this year's lunar August 15th is obviously not the roundest and brightest time of the year. This year's full moon will appear at 2: 40 on June 6, 65438. 10 year 10 from 3 to 5 October, the distances between the moon and the earth were 379,223 km, 374,785 km and 3765,438+0096 km, respectively, which means that the distance between the moon and the earth is getting closer every day, and people can see the moon bigger every day. 10 In the early morning of June 6th, the roundest Mid-Autumn Moon can be seen all over China.
Because the moon is in the orbit around the earth due to the east direction when it is closest to the earth, the distance from the earth is getting farther and farther, which means that the roundest Mid-Autumn Moon can't be seen in parts of the western hemisphere such as Canada, the United States and Peru this year. Isn't this "China's moon is rounder than foreign countries"?
△ data map