What is the definition of leap year?

Leap years include years with leap days in the solar calendar or summer calendar, and years with leap months in the China lunar calendar. Let me introduce the definition of leap year to you, hoping to help you!

Definition of leap year

A year with a leap month in the lunar calendar is called a leap year, and the lunar calendar adopts the method of 19 plus 7 leap months, that is, the "7 leap year method of 19", that is, the lunar calendar 19 has 7 leap years.

The establishment of leap year is to make up for the time difference between the number of days in a year and the actual period of revolution of the earth caused by man-made calendar regulations. The year to make up for the time difference is leap year. Leap year * * * has 366 days (February is 1- 1 day, 29 days, 3 1 day, 30 days, 3 1 day, 3 1 day respectively).

Where the solar calendar has a leap day (February 29th) or the lunar calendar has a leap month (there are thirteen months in a year); Leap surplus (leap surplus). Time difference between lunar calendar and tropic year.

Specific source

Su Songshi's Four Poems of Doctor Xiao Gong's Residence in Yu Kang's Langzhong: "There are countless plants and trees in the garden, only leap years." Song Luyou's poem "My Dwelling House": "The wheat is damaged by rain, and the silkworm is late to welcome the leap year." Yue's Notes on Tea Room: Pipa Should Jump on the Moon: "A pipa has twelve sons, and in leap years there are thirteen sons."

What is a leap year?

The establishment of leap year is to make up for the time difference between the number of days in a year and the actual period of revolution of the earth caused by man-made calendar regulations. The year to make up for the time difference is leap year. Both the Gregorian calendar and the lunar calendar we are using now have leap years.

The calculation of leap years in the Gregorian calendar is relatively simple: the Gregorian calendar leaps every four years, does not leap in one hundred years, and jumps again in four hundred years. The leap month is set as February, and the leap day is set as February 29th. The calculation of lunar leap year is a little more complicated. Let's talk about the calculation method of leap year in lunar calendar in detail.

According to the lunar calendar, the moon is determined by the cycle of the first month of the lunar calendar, and the contradiction between tropic year and lunar year is coordinated by placing leap. On the basis of astronomical observation, our ancestors found out the method of adding seven leap months in 19, that is, the "seventeen leap months in nineteen years", which well coordinated the tropic year and the lunar year, and kept the Lunar New Year in the late winter and early spring. At present, the method of setting leap is between two winter solstice. If it is only 12 months, it is not a leap; if it is 13 months, it is a leap. The leap month begins on the "winter solstice". When the first month without "neutral gas" appears, this month is a leap month, and its name is to add the word "leap" in front of this month. What month is the lunar leap month? This depends on the 24 solar terms.

In the China lunar calendar, 24 solar terms are divided into 12 solar terms and 12 solar terms, among which odd numbers (beginning of spring, Changxia, etc. ) are solar terms, even numbers (rain, vernal equinox, etc. ) is called a neutral term. The lunar calendar takes the moon as the cycle (lunar calendar), and the December calendar is about 354 days. Combined with the almanac (solar calendar), the almanac is compiled according to the four-season cycle formed by the revolution of the earth. The monthly calendar is shorter than the annual calendar by 1 1 day. Therefore, it is necessary to add 7 leap months every 19 years to make up for the error. Deciding which month is a leap month depends on 24 solar terms. Lunar months usually include a solar term and a neutral atmosphere, such as the autumnal equinox. If a lunar month has only solar terms but no neutral atmosphere, one more month will be added to the calendar as a leap month. Take this year (20 17) as an example. June of the lunar calendar happens to be a month with solar terms but no gas, so the error is adjusted in June.

The date of the twenty-four solar terms of the lunar calendar is postponed month by month, so in some lunar months, the gas falls at the end of the month, and it will be out of gas next month.

Generally, there will be a month without gas every two years, which coincides with the year when leap months are needed. Therefore, the lunar calendar stipulates that non-neutral months are leap months. Naturally, that month was a leap year.

;