Magic Calendar For PickingA Red—letter Day

By Zhou Yali

Spring Festival finally comes！ Everyone could not help sighing that why the Spring Festival in this year comes so late？ Who prescribe the date for the Spring Festival？ They do not know that we are so anxious to wait for the Spring Festival？ Now we'll take a look at the magic calendar for picking a day！

There is an argument for

when to begin a New Year

On most calendars， there will always be a line of small Chinese characters below larger Arabic numerals. It says the current solar term， marks the festival， and determines the end and start of a year， which is the traditional Chinese calendar.

Although people usually call it "lunar calendar"， in fact， the traditional Chinese calendar is a lunisolar calendar. So the traditional Chinese calendar seems quite powerful， both "lunar" and "solar"， which is contradictory， isn't it？ Hey， this reflects the wisdom of our ancestors！ "Solar" here refers to the sun， and "lunar" refers to the moon. There are 24 solar terms in the lunar calendar set based on the locations that the sun directly irradiates the Earth， which is the "solar" part； while months are identified based on the phases of the moon， which is the "lunar" part. As the first day of the New Year， significance of the Spring Festival is naturally unusual. How is this day set？ The first day of a year， of course， is also the first day of the first month. In the lunar calendar， the winter solstice is a very important solar term， and the month in which the winter solstice occurs is called "Month Zi"， next month is called "Month Chou"， and the next month but one is called "Month Yin". In the lunar calendar， "Month Yin" is the first month of the beginning of a year. The first day of a month is jointly determined by the rotation cycles of the sun， the earth and the moon. On that day， the celestial longitude of the sun is equal to that of the moon， people cannot see the moon at night， and the ancients called this day as "the first day of a lunar month".

Why the date in solar calendar for the Spring Festival changes each year

On January 30， 2014， the whole family had the family reunion dinner bustlingly. However， in 2015， people look forward to this reunion dinner until February 18.

January 1 opens the screen of a New Year according to the date in Arabic numerals on the calendar！ Why there is so much difference between the two dates？

Date in Arabic numbers you see is the solar calendar we usually talk about， also known as Gregorian calendar， and is from Europe. Previously， the Chinese people used the traditional lunar calendar， switched to use the solar calendar after the Revolution of 1911， and kept in line with most of the countries in the world.

Gregorian calendar is the real solar calendar， which relates to the annual motion of the Earth around the Sun. The solar calendar today came as soon as Pope Gregory XIII improved Roman calendar in 1582. It takes 365.242 days for the earth to go all the way around the sun， so a year in solar calendar is 365 days， and there is a leap year every four years， which has a day more. Solar calendar is simple， and easy to remember， dates of some festivals are fixed in solar calendar. Compared with the solar calendar， the lunar calendar is unpredictable. However， the lunar calendar is also of a lot of advantages， it can conduct friendly cooperation with all kinds of astronomical phenomena， for example， in the lunar calendar， the height of the Sun can be seen based on specific solar term， and phases of the Moon， tides， etc. can be reflected through the day of a month. Both solar calendar and lunar calendar are laws summed up by people based on their observation and thinking on nature.

It is the leap month that should be blamed

In fact， why the Spring Festival in 2015 comes so late is because there is a leap September in the lunar calendar in 2014. Sometimes， you will find the word "leap X" in the calendar. A month appears twice in a year？ This is not a mistake in the calendar. Let's calculate the number of days in a lunar year！ There are six 30-day months and six 29-day months in a lunar year， so there are 354 days in a lunar year. It is wrong， there are 365 or 366 days in a year， isn't it？ How come 11 days are lost？ This does not meet the actual cycle that the earth goes around the sun！ So leap month emerges to make up the lost days.

Through calculation， the ancients could make the lunar calendar closest to the actual situation by setting "7 leap years in 19 lunar years". In simple terms， it is to set 7 leap years in 19 lunar years and there is a month more， namely the leap month in each lunar year. According to the calendar rules， a leap month is arranged after a certain month to repeat the month. In other words， there are 13 months in a leap year， thus， there are 383 or 384 days in the whole lunar year. And the average of the total number of days of the 19 lunar years is close to 365.242 days， which happens to coincide with the number of days in a calendar year！ You also admire the wisdom of the ancients， aren't you？