Mythical Version of the Three Kingdoms

The Gan and Shi families have accumulated thousands of years of experience in astronomy and climatology. Even if we don't count the period before the Ji family, it has been more than 600 years since these two families produced the first astronomical work in human history.

In these 600 years, the two families have accumulated a large amount of astronomical, hydrological and climatological data.

After being hit by several heavy hammers of super-large-scale catastrophic climates, the Gan and Shi families finally woke up - we need to make a large and accurate thing that integrates all the family data and can be passed on.

Of course, there is a very important point here. There are too many data left by the ancestors of these two families. Even if some of them were lost or damaged during the period, the number of bamboo slips is enough to crush people to death.

So this group of people planned to classify and organize them, and in this process, the son of the Shi family brought Wan Zhen to the two families. He listened to the younger brother of the Shi family explaining the stars, and then a flash of inspiration came up with the magical operation of planetary positioning.

As I said before, Wan Zhen is a true genius. His spiritual talent of knowing everything can bring out amazing results in his hands. He only needs to know the beginning of many things to analyze a lot of magical uses.

Combined with the messy knowledge he has mastered before, it is like playing to open a new skill for you on the spot. Although in theory, there is nothing developed by Wan Zhen in the new skills he opens. His skills are all messy things picked up from other people, and then he relies on his amazing ability to piece together to create raw goods.

However, you have to admit that Wan Zhen is really a god in the world of patchwork. He can always piece together a set of very amazing things from some messy things.

For example, chatting with the children of the Shi family, learning astrology and sea navigation, soon after learning, he combined his knowledge of mathematics, astrology, sea navigation and clocks to come up with planetary positioning.

For example, in the official history, Wan Zhen has never been to the South Country, but he wrote the "Nanzhou Yiwuzhi" which is very correct and has great reference, quotation and reference value.

For example, Wan Zhen actually has the fourth level of smelting now, and he has combined his own understanding of talent to come up with a talent smelting and transformation logic book, as well as talent architecture combination optimization, which has successfully made him keep up with the combat effectiveness of the Iron Cavalry Headquarters.

Because he had experienced war, he also learned some military command, and then combined Chen Xi's modular concept, some things taught by Huangfu Song, and the war experience of the Xiliang Iron Cavalry to come up with a set of military command techniques for his own use. If nothing else, he has no problem commanding a legion.

This guy is a real god, but he doesn't want to be an official, nor does he want to stay at home, and he doesn't feel like having children, so he just wanders around the world every day.

In the process of traveling thousands of miles, Wan Zhen also wrote a lot of useful things, and this time the two heads of the Gan and Shi families came together, and they also read some of Wan Zhen's records before deciding to conduct astronomical and geodetic measurements in advance.

Chen Xi didn't know these things, but since these two families wanted to do this, Chen Xi roughly knew how far these people had developed.

"This project is not small." Chen Xi said with a very serious look, "and since you want to measure, there will probably be more than that. Tell me what you have discovered first, and then I will see how much you have invested."

Astronomical and geodetic surveys require a lot of manpower and material resources. The first astronomical and geodetic survey during the reign of Emperor Xuanzong of Tang Dynasty did not mention the manpower mobilized. The measured points alone, from 51 degrees north latitude (Ulaanbaatar, Mongolia) to 18 degrees north latitude (Vietnam), exceeded the current land territory of China in the north and south.

To be honest, this kind of actual measurement method was not affordable in the feudal era unless the country was at its peak. Moreover, the territory was not large enough, and the control samples were not enough, so it was impossible to be accurate.

And Chen Xi thought that this matter was indeed necessary. After all, the astronomical knowledge he mastered was not actually accurate in this era. The existence of precession and nutation caused some astronomical knowledge used by Chen Xi to actually have errors.

Of course, the laws are the same, but the basic terms have changed. But to be honest, the foundation has changed, and the results calculated by the laws can only be used as a reference.

However, the Han Dynasty rarely touched upon things that are affected by precession and nutation, such as the true rotation axis, true celestial pole, true celestial equator, instantaneous true vernal equinox, etc.

To be honest, these things have no effect on ordinary people.

So Chen Xi has always been muddling along, but now it seems that the intention of the heads of the Gan and Shi families is to solve these together. If you think about it, these things are necessary parameters if you want to accurately study atmospheric circulation.

After all, the true rotation axis affects the position of the pole. Under the combined effect of the gravity of the sun and the moon and the movement of the earth, this thing will produce an offset, which is why the position of the pole will move over time.

This thing is related to the exact position of the concept point of north and south, and is an indispensable parameter for accurately constructing a dynamic planet.

Of course, this thing is thrown aside first. In fact, as long as the precession and nutation are understood, these things can be calculated by hard calculation. The so-called precession is actually the time difference between the sidereal year and the tropical year.

The tropical year is simply the time it takes for the sun to pass through the vernal equinox twice, while the sidereal year is the time it takes for the earth to orbit the sun and return to the previous point. The difference between these two times is the precession of the equinoxes.

Of course, this is a concept in time. The real reason for precession is actually the change of the true rotation axis mentioned above, and the change of the true rotation axis is the joint result of the gravity of the sun and the moon and the movement of the earth.

The logic of nutation is similar to that of precession, but nutation is caused by the change of the distance between the earth and the moon. We have learned about universal gravitation and the orbit of the earth and the moon, so it should not be a problem to understand the influence of the moon at perigee and apogee on the earth.

This kind of gravitational pull causes the rotation of the earth on the great circle of the star orbit to be not completely smooth, but with a peak and a trough, which is nutation.

These two things affect a lot of things at the same time, which is the basis that must be considered in astronomy.

So Chen Xi must understand what level Gan and Shi want to achieve. If it is just the level of the Tang Dynasty, Chen Xi will send three to five hundred professionals and hundreds of millions of money. If they have realized the influence of the gravity of the sun and the moon on the true rotation axis, and consciously adjusted the true rotation axis, and even determined the earth's pole, then Chen Xi can invest more.

"First of all, it's the problem of solar phenomena. There is a lot of information in the family that can prove that the time of solar eclipse and the eclipse phenomenon seen will be different in different observation locations. The same is true for the length of the sun's shadow and the division of day and night in each solar term." Gan Bao saw Chen Xi asking, and he knew that every word of the current answer was related to the subsequent funds and manpower.

Of course, funds are not important. If you don't have money, you can go to other families to beg for alms. Anyway, there are still hundreds of gold bricks in Runan Yuan's family. Grab them to replenish funds. At most, you will be scolded by the Yuan family. It's not a big deal.

The real trouble is manpower. If Chen Xi agrees, the number of professionals that can be transferred will increase significantly. For example, gods like Wan Zhen and Zhao Shuang can also be caught to work, which is very important for Gan and Shi.

"Well, this is a problem of latitude and longitude. This is easier to do. I can approve 200 million yuan for you to conduct actual measurements at different latitudes and the same longitude, and then calculate the length of the meridian based on the angle difference." Chen Xi nodded. This can be done as long as you pay money, and it is very meaningful.

As for why it is still called the meridian, because the earthly branch Zi represents due north, Wu represents due south, and the original meaning of the meridian is the line from due south to due north. If this thing is calculated, combined with the circumference of the earth, we will realize that the earth is an ellipsoid, and the ellipsoid has some characteristics. As long as we realize that the earth is an ellipsoid, many things will be inferred.

"Speaking of which, you actually don't talk about the induction between heaven and man. This is a solar eclipse, the bright sun, you don't respect it at all." Chen Xi said, and asked with a teasing tone.

"We have already calculated this. One degree of the meridian is about 111 kilometers." Shi Tao waved his hand and said that they had already calculated it with other people's gold coins. "As for the induction between heaven and man, our two families don't play this kind of thing very much. It's fun to cheat others, but cheat us? Oh, we don't have money to cheat those who play the induction between heaven and man, let them cheat others..."

Chen Xi was speechless after hearing this. He lowered his head and recalled the encyclopedia he had read. The difference with this data was very small, and he understood that Gan and Shi had already had a fairly deep understanding in this regard.

"You have calculated the length of the meridian, and have followed Jiang Dong to the equator and calculated the length of the equator. Haven't you found any problems yet?" Chen Xi asked curiously.

"Isn't it a perfect sphere?" Gan Bao said uncomfortably, grabbing his head. For someone with obsessive-compulsive disorder, it is really uncomfortable to be just this close to a perfect sphere.

"So you know, but you just don't want to accept it, right?" Chen Xi said with a smile. The earth is not a perfect sphere, but an ellipsoid. Although it is very close to a perfect sphere, some things are almost not a perfect sphere.

"Forget it, let's continue talking about the problems we found after reading the data." Gan Bao said with some discomfort, "The orthographic sphere is only one aspect of the problem. In fact, after having the atmospheric circulation map and planetary positioning as a reference, we actually found a lot of things by comparing the ancient records, such as tides, precession, and the declination of the earth's poles."

"Well, the declination of the earth's poles, you have already discovered the pole shift, right?" Chen Xi pondered for a moment, and said with some thought, "That means you will measure the pole shift for a period of time next. By the way, how do you plan to measure this thing? Where to measure it?"

Shi Tao's mouth was bitter when he heard this. He lost the game of rock-paper-scissors with Gan Bao. Their family sent people to the Arctic Circle to measure the geographical poles and geomagnetic poles. Although they had this idea a long time ago, it would be very difficult to measure them.

"When the time comes, I will lead the Shi family to the Arctic for actual measurement." Although it is bitter, Shi Tao must be righteous at this time.

"I remember that the Yong family seems to be in the Arctic Circle. You can discuss with them and stay at the Yong family's place. It happens that there will be a grand court meeting this year, and the Yong family should come. You can discuss it then." Chen Xi thought for a while and suggested.

After all, if you want to measure this, you can only go to the Arctic Circle. After all, going to the Arctic Circle and feeling the polar night will also help these guys understand the realistic concept of the ecliptic plane.

As for the troublesome Yong family, even if they stay at home, they still need a starry, climate and calendar family like Ganshi. This family stands at the top of almost all families in the agricultural society.

Although they are not well-known and have low official positions, official positions will be continuously assigned to this family, and there will be no political conflicts. As long as they do their own things well, everything will be arranged from birth to death.

Therefore, even if the Yong family is a stay-at-home family, they have to give face to such a family when they go there for field research. After all, if someone stays with you for a while, they can help you write a local calendar, which will save you a lot of trouble in farming in the future.

"We also considered the Yong family, but we don't know what's going on with the Yong family and can't contact them. We plan to contact the Yuan family first. The Yuan family said that they also have a station in the north of the Ural Mountains near the North Pole, which can allow us to study there first and provide us with protection." Shi Tao said that he understood that they really considered the Yong family, but they couldn't find the Yong family.

"The Yuan family is also okay. Anyway, you should be careful. The Yuan family's sugar-coated offensive is very fierce." Chen Xi said casually.

"We also know this. We previously supported five astronomical figures of the Yuan family, and four of them have married and had children in Sizhao City." Gan Bao said helplessly, "In addition, when the major families left, they married daughters of our family, so now there are less than 120 people in our two families who can work. I am really impressed."

Women can also work. In recent years, the internal blockade of family clan studies is not serious. In addition, due to the shortage of manpower, women will also be pulled to do odd jobs. After a long period of exposure, most women in the Gan and Shi families are still reliable in hydrological and climate research. At least they can record data and make judgments according to the table step by step.

In the past, there were more than 200 working people in the Gan and Shi families, but now there are less than 120 left. Some of them are married, or other families offer high prices, so they join other families to fool around. Considering that some old men and women are no longer able to undertake field survey tasks, the manpower of the Gan and Shi families can be said to be further stretched.

In addition, the current territory of the Han Dynasty has greatly increased, and the newly occupied territories must at least produce a basic farming calendar, which has led to a lot of work for everyone. This is also the reason why the older generation retired directly. They can't stand it anymore. They really can't stand it.

"Where are the new people trained?" Chen Xi asked curiously. If I remember correctly, the Gan and Shi families have realized this problem since five years ago and have been training new people. It seems that there is no product, right?

"We have tried our best to recruit children under ten years old, but most of the children recruited have zero knowledge of astrology and climate." Gan Bao had nothing to say.

Chen Xi was helpless when he heard this. In this day and age, even if the children recruited are descendants of aristocratic families, it would be a miracle if they can have knowledge of astrology and climate.

"Forget it, let's continue talking about the astronomical geodesy you want to do." Chen Xi sighed and said, there is no way, there is no newbie to inherit, so he can only do it slowly. The popularization of this kind of basic knowledge does take time.

"We already know something about the precession, but the accuracy needs to be calculated. We have also found evidence of the influence of the moon on the tides and planetary rotation from the data of the past few hundred years, but all of them need precise measurement and calculation." Shi Tao said with admiration for his ancestors.

As I said, some ancestors of the Gan and Shi families did modify and adjust the records manually when they found that the records were illogical, but there were also some who recorded them honestly and said that this is what I recorded, and the reality was not logical. I think we may have made a mistake. You latecomers can calculate it when you have time.

Over the past six hundred years, there have been many people who manually modified and adjusted the data to ensure that the difference with their own calculations was not large, but there were also many people who realized that there was a problem with their own calculation formulas, but could not find the problem, and recorded it truthfully.

In this era, with the concept of the earth being a ball and the atmospheric circulation, it is still possible to filter out the correct data from many recorded data after mutual verification and comparison.

Even if the screening conditions are extremely harsh and the accuracy of the records must be guaranteed, there are tens of thousands of records in the archives of more than 600 years, and then they are verified and compared with each other. Under the concept of planets, many things that were originally ignored are naturally picked out.

Concepts such as precession, nutation, geomagnetic poles, geomagnetic poles, ellipsoids, and angles of the ecliptic plane have been forcibly reversed by these data, and even the concept of gravity has been forcibly pulled out and supplemented.

Although the constants have not been calculated, the concepts have been introduced into it. The vacuum pendulum from the northern border to the equator is enough for Gan and Shi to calculate the range of gravitational acceleration. These are all very big progress.

It’s just that this group of people really can’t figure out the gravitational force. Lord Niu is really a true god to some extent. Fortunately, Chen Xi is not in a hurry.

After all, this group of people has reversed Kepler’s three laws with the information of their ancestors. It seems that they are still one step away from Lord Niu.

But it doesn't matter. They can achieve this level, and also introduce the concept of gravity. Sooner or later, a true god will come up with the law of universal gravitation. Now let's see how Gan and Shi do it.

"Have you considered how long it takes to observe this thing?" Chen Xi asked with some curiosity.

"The influence of the moon phase tide on the rotation of the earth, we estimate that it will take a generation, the previous one..." Gan Bao looked at Chen Xi awkwardly. They didn't know how long it would take, but it must be very long anyway.

"What about the mathematical calculations?" Chen Xi looked at the two speechlessly.

Slipped away, slipped away, the author is really useless, sigh