Recreating the prosperous Tang begins with summoning players

Q: For a wise king, which achievement would go down in history?
Answer: Including but not limited to the following:
Open up the frontiers and expand the land, enshrine Zen and Mount Tai, compile an anthology of anthologies, and rewrite the calendar.

Li Heng didn't have to think about opening up the frontier and expanding the territory. It would be nice to be able to regain the original territory of the Tang Dynasty.

Fengchan Taishan is still in the struggle between Datang and Puppet Yan in the Shandong area. It is estimated that Li Heng will be sprayed to death by the officials if he proposes it.

"Book of Jin" had already been compiled by Fang Xuanling during Taizong's reign. As for the anthology, Li Yan did not have the time to do so.

Then all that's left is to reset the calendar!
The calendar is the most fundamental law of the entire dynasty.

In an agricultural society, the calendar is not only used to calculate the date, but also a guide to guide agricultural production.

As Li Longji's next emperor, Li Heng is undoubtedly quite sad.

If there was no Anshi Rebellion, or if Li Longji died earlier, he would be a wise and mighty emperor.

Li Longji did it to open up the territory and expand the territory of Datang to a point that later generations could not reach.

Li Longji also did Fengchan Taishan. In the 13th year of Kaiyuan, under the auspices of Prime Minister Zhang Shuo, Tang Xuanzong Li Longji led hundreds of officials, noble relatives and Siyi leaders from Dongdu to Mount Tai to enshrine Zen.

Li Longji even re-set the calendar.

The calendar currently implemented in the Tang Dynasty is called Dayan Calendar, also known as "Kaiyuan Dayan Calendar".

He was a famous mathematician and astronomer during the emperor's period. The monk and his party wrote it with reference to "Nine Zhili".

It got its name because the legislation was based on the number of Xiang Dayan in "Yi".A team measured the latitude of various places, from the south to Jiaozhou and the north to Tiele, and set up nine sundials to determine the eclipse scores of various places, and retested to see the movement of stars.

However, the Dayan Calendar has been implemented to this day, and due to the original accuracy problem, there have been deviations.

Wei Yuan's suggestion was to revise a more accurate astronomical calendar and submit it to the emperor.

Li Yan couldn't help but be overwhelmed by this proposal!
Li Yan knew very clearly what his father needed.

Living in the shadow of the emperor for most of his life, Li Heng spent the rest of his life wiping Li Longji's ass.

It was obviously Li Longji who had collapsed the country, but Li Heng was required to regain it bit by bit.

The emperor did everything he could, so what if Li Heng quelled the Anshi Rebellion, his health is not good, so don't even think about opening up territories and enshrining Chan Taishan.

Li Yan knew that his father would be very happy to receive this gift.

Because this is something beyond the emperor!

Revising the calendar of the emperor's period is more reflective of the renewal of Vientiane than changing the year name!
Moreover, resetting the calendar is something that only a strong dynasty can do.

The calendar is not only a mathematical problem, but also an astronomical problem.

In order to revise the Dayan calendar, the emperor established dozens of astronomical observation stations from the southernmost Jiaozhou to the northernmost Mobei grassland.

These observatories calculated the position of the stars, calculated the time of the stars' rise and fall, drew star maps, and finally sent them all to Chang'an. Under the leadership of the monk and his party, they calculated a big Yan calendar.

It can be said that this is a systematic project that can only be carried out by the prosperous dynasty.

In ancient times when the communication conditions were mediocre and the observation level was also very backward, the revision of the etiquette law was indeed a huge and complex systematic project.

He and his party began to rewrite the calendar in the ninth year of Kaiyuan, and died in the 15th year of Kaiyuan. Datang gathered astronomers and mathematicians from all over the country to calculate the manuscripts left by the party, and it was not promulgated until the 17th year of Kaiyuan.

But the emperor will move back to Chang'an soon, is there enough time?
Wei Yuan also proposed an answer to this question, and time is enough.

The most important thing about the calendar is the period of the earth's revolution, and players naturally have mastered this number.

Now that the players are in the north and south, especially the distance from Longyou to Liaoxi, all the players along the way need to take pictures of the astrology to Wei Yuan, and he can re-establish a etiquette according to the astrology.

Moreover, Wei Yuan didn't want to come up with the sophisticated rituals of modern times, his goal was to create a ritual of the same level as the Yuan Dynasty's Shushi Calendar.

The timing calendar has been used for more than 300 years, and its accuracy is almost the same as that of the modern Gregorian calendar, which is enough for the current Tang Dynasty.

The plan can be implemented, as long as players distributed all over the country provide astronomical observation data, Wei Yuan can compile a more accurate and practical calendar.

Replacing the old calendar with the new one also shows the appearance of the new emperor ascending the throne. Father will definitely like such a gift!

However, things like the revision of the calendar still need to be reported to the emperor.

After all, the calendar is the most fundamental matter of the country, and the emperor can appoint King Jianning to do it, but it is not good to do it privately.

As long as the revision is successfully presented to the emperor, the credit belongs to the emperor.

Thinking of this, Li Yan immediately contacted Shangbo in the backyard of Fengxiang Mansion and asked him to ask the emperor for authorization.

According to the wind in Fengxiang Mansion, moving back to Chang'an is a big project, and the emperor will definitely wait until all the officials and ministers return to Chang'an to settle down, clean and repair the Daming Palace before returning to Chang'an.

This calculation will take at least two months.

Report now, and give gifts when they move back to Chang'an. The time is about the same as Wei Yuan planned.

Shang Bo quickly found Prime Minister Pei Mian, and directly submitted King Jianning's memorial to the emperor through Zhongshumen.

"My son wants to revise the calendar?" Li Heng was startled when he saw his son's memorial.

When the Dayan Calendar was promulgated, Li Heng was not yet the prince, but he was already an adult at that time.

But the grand occasion promulgated by the Dayan calendar at that time is still printed in Li Heng's mind.

Qin Tianjian cast a golden armillary sphere, and cast 49 bottles of golden timekeeping hourglass.

The Dayan Calendar uses the number 49 of Dayan as a basic unit, and takes eight years as a time period.

When the calendar was promulgated, a grand celebration ceremony was held in Chang'an City.

Li Longji personally prayed to God and the ancestors, reported the completion of the calendar, and pardoned the criminals under the death penalty, and the whole world celebrated together.

Then Li Longji held a banquet for three days and three nights in Huaelou, and the promulgation of the Dayan Calendar is also one of the indelible symbols of the prosperity of Kaiyuan.

Li Heng couldn't help feeling excited, but he still asked Prime Minister Pei Mian:

"Is it necessary to rebuild the new calendar?"

Pei Mian also did his homework, and he immediately said: "Although the Great Yanli Calendar is good, since the Tianbao period, the rooftops of the governors in various places have gradually become useless, and there are already many fallacies."

"Last month's calculation of the lunar eclipse time was off by a full hour, and the dates of the winter solstice and autumnal equinox were also inaccurate."

From the moment Li Heng saw his son's memorial, he had the idea of ​​repairing the new calendar. Hearing what the prime minister said, Li Heng felt better.

But he still asked: "Will it cost too much money to build the new calendar? It took the emperor half a year to complete the Dayan calendar, how long will the new calendar take?"

Li Heng's health is not good, if he waits another eight years, maybe he won't be able to survive the new calendar.

Pei Mian said: "I heard that the materials of the Great Yan Calendar are still available, and King Jianning found a genius in the Western Regions who is proficient in mathematics. He said that he can complete the new calendar before returning to Chang'an."

The memorials of all the officials have to go through the Zhengshitang, and Pei Mian has read the detailed memorials.

Under Pei Mian's reminder, Li Heng saw the time and schedule detailed by Li Yan behind.

He smiled and said, "My son is so loud!"

Li Heng only thought that this was his son bragging for himself, but he still received this kindness.

He said to Pei Mian: "Since my son has this filial piety, let Hanlin draft an edict and let King Jianning preside over the revision of the new calendar."

Then Li Heng said: "There is no need to rush back to Chang'an to complete the revision. The new calendar is more accurate than the Dayan calendar."

Pei Mian immediately said: "Observe the order."

Wei Yuan, a player who had thirteen tests, wrote to King Jianning to suggest a revision of the calendar, and this suggestion was adopted by King Jianning.

The news spread all over the player forums!
Then there was a new news that King Jianning spent money to help Wei Yuan build an observatory outside Jiuquan City.

At the same time, observatories were also built in Mobei, Modong, and Liaoxi.

And those players wandering outside Longyou also received new missions.

[Special Mission: Observing the Starry Sky]

【The greatest thing in the world is the vast sky above our heads. 】

[Follow the game prompts to provide daily sky observation data.Make a simple device to measure the time of sunrise and sunset. 】

[Task Reward 1: Players who complete the task can get professional experience rewards. 】

[Mission Reward 2: Rare title - Star Observer and corresponding forum badge. 】

I have to say, this is the easiest task.

All you need is for players other than Longyou to go online regularly every night, take pictures of the star map above their heads, mark the positions of important stars and upload them to the forum.

For these adventurous players, it can be said that it can be completed easily, and the reward can be obtained immediately after completion.

This may be the easiest task to obtain a title. As soon as the task was sent out, it immediately received a large number of players' responses, and a huge amount of data was sent to the forum.

For Wei Yuan, this is not a very difficult task.

As a mathematician, mathematical analysis and processing data is nothing but the simplest work.

The formulation of the calendar is actually to calculate the revolution period of the earth, and determine the rotation speed of the earth through the changes in the positions of the stars in the starry sky.

For Wei Yuan, such questions can only be regarded as more challenging.

The reason why the big Yanli calendar takes a lot of time is because one line spent too much time looking for the "shangyuan product number".

Shangyuan product number is the "beginning of heaven and earth" that ancient astronomers were looking for.

It is also the day when the calendar stipulated by astronomers begins, and the Shangyuan product calculated by one line is the day when the five stars in a row, the sun and the moon are in the same orbit.

In order to calculate this upper element product, one line takes too much time.

But to Wei Yuan, Shangyuan product has no meaning at all.

He directly took the year when the First Emperor destroyed the six kingdoms and unified the world as the first year of AD, which is the starting point of the calendar.

This set of calendars is directly based on Guo Shoujing's time-serving calendar of the Yuan Dynasty, with 365.2422 days as a year, and its accuracy is comparable to the "Gregorian Calendar" currently in effect around the world.

Wei Yuan recalculated the winter solstice and summer solstice dates for the next hundred years, and calculated the times and locations of several major solar and lunar eclipses.

Seeing this new calendar, Li Yan was overjoyed. This will be the best gift for the emperor to return to Chang'an, bar none!