65438+February 15 What's the date of the lunar calendar?

65438+February 2020 65438+May corresponds to the lunar calendar: the first day of the winter month in the Year of the Rat.

Conversion between Gregorian calendar and lunar calendar

Many people have been looking for formulas to change the lunar calendar. However, due to the instability and irregularity of the moon's rotation, there is no formula to find, that is to say, there is no calculation method for the conversion between the Gregorian calendar and the lunar calendar, which is also the reason why the calendar must be changed every hundred years in ancient China.

How often does the Gregorian calendar coincide with China people's birthdays?

Generally, the Gregorian calendar falls on the same day every 19 years. No matter the month of the lunar calendar or the year of the solar calendar, their exact dates are not integers but decimals. 19 The dates of the lunar calendar and the solar calendar are still slightly different. After decades or even hundreds of years of accumulation, decimals become large numbers, which leads to the phenomenon of non-coincidence, but generally only one day away, either in advance or delayed.

Why?

This situation is mainly the result of the leap of the lunar calendar. 19 Why is there a coincidence? The number of days in each month in the lunar calendar is determined according to the cycle of the moon. In fact, the average number of days per month is 29.5306. If multiplied by 12, there are only 354.3672 days in a year. One revolution of the earth around the sun (tropical year and solar year) is 365.2422 days, so the lunar year 1 the actual number of days is less than that of the sun 10.875 days, almost 1 1 day, 19 is 209 days less.

209 days divided by 30 is 6.9666. 19 years, the lunar year is almost 7 months shorter than the solar calendar. In order to make the difference between the lunar calendar and the solar calendar not too much, it is necessary to make up these seven months.

The lunar calendar in China is actually a typical lunar calendar, which is a combination of lunar calendar and solar calendar. In order to make up for these seven months, people adopt the method of setting leap months in the lunar calendar-seven leap months in nineteen years, that is, nineteen years of the lunar calendar, with 12 as a normal year and every 1 as 12 months; Plus seven leap years (3, 5, 8, 1 1, 14, 17, 19), every 1 leap year has 13 months.

In this way, the number of days in the 19 solar year is almost equal to the number of days in the 19 lunar year. Therefore, whenever the birthday is 19 or 19 multiplied by the age, there is a chance that the solar calendar birthday and the lunar calendar birthday are on the same day.