Sun Yi didn't expect it.

A date code was so important in the hearts of the Ming Dynasty people that the chief of staff and military advisers had to figure it out regardless of the war, so that Sun Dingliao, who had always been anti-Manchu and not anti-Ming, began to firmly declare that the Ming Dynasty emperor was Chongzhen's little pseudo-emperor.

In Sun Yi's view, people in this era have very funny obsessions.

For example, people on the grassland will be suffocated to death if they don't drink tea; Make a little puppet and stick a needle to curse people to death; If the calendar is wrong, the dynasty will be overturned.

They also don't want to think about what to do with war if these magic tricks work?

But when everyone looked at Sun Yi's expression, they were either filled with righteous indignation, or they were sincere.

Sun Yi's sweat suddenly fell.

It seems that since it is an obsession, if they don't explain this matter today, they have no intention of fighting.

These days, Sun Yi has basically an understanding of the calendar of the Ming Dynasty.

The calendar of the Ming Dynasty is simply a three-in-one solar calendar, a lunar calendar, and a dry calendar.

The solar calendar is based on the sun's celestial orbit as a cycle, with the sun orbiting the earth as a day, and the winter solstice to the next winter solstice as one year.

The ancient calendar before the Han Dynasty set a year old as 365 and 1/4 of a day, and the calendar after the Han Dynasty specified the length of a year as more precise. For example, the Chinese calendar stipulates that it is 365 and 385/1539 days; The first year is divided into twelve sections, with the ordinal number of "Zi Chou Yin Mao Chen Si Wu Wei Shen Youxu Hai", and there is a qi in the center of each section; The 12 nodes and the 12 Zhongqi have their own names, which are collectively known as the 24 solar terms.

The lunar calendar takes one cycle of the moon as one month, with 30 days for the big month and 29 days for the small month. Since the Tang Dynasty, every month starts from the "New Year", which is the first day of the new year. The so-called "Shuo" means that the moon orbits exactly between the earth and the sun, and the three are located in the same plane. At this time, the Sun is behind the Moon, and no bright part of the Moon can be seen from the ground.

China's lunar calendar stipulates that the first day of the first month of the first month of the month of the year is from the first day of the next month to the first day of the next month. A year in the lunar calendar is not equal to a year in the solar calendar, and a year is 12 months or 12 months plus a leap month, and the length is not fixed.

The Ganzhi calendar uses the sexagesimal system of the sexagenary branch to count days, festivals, and years.

As a traditional Chinese calendar, the Ganzhi Chronicle has been used in ancient China and has never been interrupted throughout history, and can be conveniently and continuously accurately positioned forward or backward to each day.

According to the history of the Spring and Autumn Period, there was a solar eclipse on the second day of the third year of Lu Yin Gong (February 22, 720 BC). This is a precise indication that China was using the Ganzhi period as early as 720 BC.

The stem branch is not used to chronicle the month. The months of the Chinese lunar calendar have always been narrated by numbers, such as the first month, February, March, April, May, June, July, August, September, October, winter moon, and wax month.

The "Bingwuyue" and "Ding Weiyue" often said in later generations are actually misinformation. The ancients used the Ganzhi era as "festival", which should strictly be called "Bingwu Festival" and "Ding Wei Festival". The Bingwu Festival is commonly known as the "Afternoon Moon" and "Afternoon Horse Month", which is a period of time when the mango is planted in the solar calendar to the summer heat.

With these basic knowledge, Sun Yi took two imperial calendars at the same time to compare and view.

The paper of Jia Daoshi's imperial calendar is much worse than that of Dahai's imperial calendar, very shabby, and there is an extra line of small characters on the cover: Yan'an Mansion is engraved and not circulated in Beijing.

Sun Yi asked: "Why can't this imperial calendar of Yan'an Mansion be circulated in Beijing?" ”

Daoist Jia replied: "The number of imperial calendars needed by the people every year is huge, and the Jingshi can't supply it. Local governments can engrave local imprints and distribute them locally, but they can't send them to the Jingshi, otherwise they will be guilty. ”

Sun Yi opened two imperial calendars.

The pages of Dahai's imperial calendar are very neat, and Jia Daoshi's imperial calendar is often circled with a brush in the daily auspicious and evil taboo column.

Comparing the content of the two imperial calendars, except for the layout font, there seems to be no difference.

As soon as Sun turned to April, all the notes on the day of April 18 in Jia Daoshi's imperial calendar were erased, and the next note was marked: Heaven and man descend, good luck.

The day in Dahai's imperial calendar reads: April 18. Bingwu, Yiyou. Miscanthus species. Big things are not appropriate.

When Sun Yi left the hotel that morning, the front desk of the hotel joked with Sun Yi, "Today is the Year of the Monkey and the Moon, and anything strange can happen, you have to be careful when you go up the mountain alone——"

Sun Yi found that day in the perpetual calendar of his mobile phone:

Sunday, June 5, 2016. The fifth month of the lunar calendar is small, and the first day of the new year. Bingshen year, Jiawu month, Wuwu day. Shuo 10:59:32. Mangzhong 13:48:28.

That is to say, at 10:59:32 a.m., the conjunction of the sun and the moon entered the fifth month of the lunar calendar; At 13:48:28 in the afternoon, it is the solar term of the mango seed and enters the noon moon of the solar calendar.

The so-called Year of the Monkey and the Horse Month, the Year of the Monkey refers to the Year of the Monkey in the lunar calendar, from the first month to the wax month, and the horse month refers to the noon horse month of the solar calendar, from the mango seed to the summer solstice and then to the summer heat.

Could it be that the sun and the moon conspired to send themselves from the first day of the Monkey Year in 2016 to the first day of the Monkey in the fifth year of Chongzhen?

Flip back, on the first day of the fifth month.

Dahai's imperial calendar shows that "the first day of the fifth month is the first day of May, and the fifth month is big." Bingwu, Wuxu".

On the imperial calendar, Daoist Jia made a big cross on the day, and marked it next to it: "April is big, May is small." It's April. In the future, the May auspicious fierce bet will not be allowed."

It turns out that the problem is here!

The official imperial calendar of the Ming Dynasty is small in April and big in May. According to the "Book of Heaven", Jia Daoshi changed it to April big and May small. The official first day of May was changed to April 30, so the days of the coalition forces after that were one day later than the official one.

At that time, the coalition army only had Jia Daoshi as a "scholar", and he had an imperial calendar, so Dayue and Xiaoyue were naturally up to him.

Jia Daoshi changed this way, and the official day today is May 30, and the day of the coalition army is May 29.

Interestingly, this year's summer solstice and the Dragon Boat Festival are the same day on Dahai's imperial calendar, and the strong note is: "The summer solstice is to the yang, the Dragon Boat Festival is to the yin, the yin and yang conflict, the big murder".

The day of the summer solstice on the imperial calendar of Jia Daoshi was changed to the fourth day of the fifth month, and Jia Daoshi himself marked it as "Kang Long has regrets". The second day of the summer solstice is the Dragon Boat Festival of the coalition army, and Jia Daoshi marked it as "No Ji Tailai".

Geng Xiucai and the bandits came to visit the coalition forces on the day of the summer solstice, and the coalition forces attacked the bandit island the next day, and at first thought that there was a plague on the island, but later found out that the bandits were poisoned.

The initiator of April is the perpetual calendar in Sun Yi's mobile phone.

The perpetual calendar shows:

"Friday, June 18, 1632. The fifth month of the lunar calendar is small, and the first day of the new year. Bingwu month, Wuxu day. Shuo 01:16:57. ”

Sun Yi secretly complained.

The sun is still sunny, and sending oneself from mangzhong to mangzhong is regarded as a point-to-point service;

The moon is too insidious to send itself away from the first day of the fifth month, but to leave it to itself on the first day of the fifth month of the destination!

The term "Shuo 01:16:57" means that at 01:16:57 in the morning, the Moon and the Sun are in the same longitude. In an astronomical sense, the new moon is preceded by the previous month, and the new moon is followed by the next.

The calendar does not divide a day into two halves, the first half of the day belongs to the previous month, and the second half of the day belongs to the next month. Therefore, it is common practice to use the day of the conjunction of the sun and the moon as the first day of the following month.

So the sun and moon are conjunct at 01:16:57 in the morning, how to calculate? Count the day before, or the day after?

If you count the day before, then the imperial calendar of the Ming Dynasty is correct, April is small, and May is big.

If you count the next day, then the perpetual calendar of the mobile phone is correct, April is big, and May is small.