China News Service, Beijing, February 8 (Zeng Yue) The Year of the Dragon is about to come, and the topic of "no New Year's Eve for five consecutive years starting next year" has recently attracted attention. Since New Year's Eve has been "New Year's Eve" for five consecutive years from 2025 to 2029, some people call February 9, 2024 the last "New Year's Eve" in recent years. In this regard, the interviewed experts said that the absence of "New Year's Eve" does not mean that there is no New Year's Eve. This is a normal phenomenon caused by the laws of the Chinese calendar.
Peng Lin, senior professor of liberal arts at Tsinghua University, said that the lunar calendar used in China is actually a lunisolar calendar, which takes into account both the solar return year, which is directly related to the sun, and the lunar synodic month, which is related to the phase changes of the moon.
The Gregorian calendar, also known as the "Gregorian calendar", is a calendar based on the length of a tropical year. The length of a tropical year is 365.2422 days, which is 365 days, 5 hours, 48 minutes and 46 seconds. The Gregorian calendar uses 365 days as a year. Since the tropical year is not an integer, there are 0.2422 days left every year, which adds up to 4 years, which is about one day more.
Peng Lin pointed out that according to regulations, the Gregorian calendar sets up a leap year every four years, adding 1 day at the end of February. Therefore, any year in which the number of years in the Gregorian calendar can be divided by 4 is a leap year. There are 29 days in February of that year, and the whole year is 366 sky. 2024 is a leap year, so February has 29 days.
The lunar calendar, also known as the "lunar calendar", is a calendar that defines months according to the waxing and waning cycle of the moon. Peng Lin explained that the calendar designates the day when the moon is completely invisible as the first day of the lunar calendar, which is called "Suo", and the day when the full moon is seen is called "Wang", from "Suo" to "Wang" Then to "Suo" is a complete cycle, that is, "Syomoon".
Peng Lin said that the Gregorian calendar is divided into big and small months. The big month has 31 days, the small month has 30 days, and February has only 28 or 29 days. The lunar calendar also has small and large months. The average length of a "synodic month" is 29.5306 days, but the number of days in a month must be expressed in integers, so the big month is 30 days and the small month is 29 days.
In addition, since the relative motion between the moon, the earth, and the sun is a natural rhythm, the determination of "Suo" must be determined based on the true positions of the moon and the sun. The moment of "Suo" may fall at any time in the day, so every day The lengths of the two synodic moons are not the same. The appearance of large and small months is not arranged at intervals, so there may be several consecutive large months or several consecutive small months.
Why does "New Year's Eve" come and go? Peng Lin said that if the twelfth lunar month of that year coincides with Xiaoyue and has only 29 days, then there will only be "New Year's Twenty-nine" but not "New Year's Thirty". "However, it is indeed rare to see this happen for five consecutive years, but whether it is the 29th or 30th of the year, New Year's Eve and its rich meaning of bidding farewell to the old and welcoming the new are still there." (End)