1969 What's the date of the seventh day of the first lunar month?

Lunar calendar 1969 The seventh day of the first month corresponds to the solar calendar:1Sunday, February 23rd, 969.

Conversion between Gregorian calendar and lunar calendar

Many people have been looking for formulas to change the lunar calendar. However, due to the unstable and irregular rotation of the moon, 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's birthday?

Generally speaking, 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 days are not integers but decimals. 19 There is still a slight difference between the lunar calendar and the solar calendar. 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 actual number of days in lunar calendar 1 year is 10.875 days less than that in the sun, which is almost 1 1 day, 19 days less.

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

The lunar calendar in China is actually a typical lunar calendar, which is a combination of the lunar calendar and the 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 (3rd, 5th, 8th, 1 1, 14, 17, 19), there are 1 3 for each leap year.

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 times the age, it is possible that the birthday in the solar calendar and the birthday in the lunar calendar appear on the same day.