Chapter 1523: Calendar (Part 3)

"Look, when the sun reaches here, it is spring, and when it reaches here, it is autumn. At this moment, the sun is here, and our Earth is here."

"Because the Earth rotates like this, it is daytime, and a while later it is nighttime. Clench your fists and look, isn't it so?"

"You put your fist next to his fist to represent the sun, you, you use your fist to represent the moon, you look, is it rotating like this?"

"Daytime, nighttime, is it clear? The four seasons, is it clear? Rotating one circle like this is one year!"

Baifeng gestured and drew, finally managing to explain the movement of the Solar System roughly. The knowledge he had once forgotten was also thoroughly remembered during the teaching.

And these people who stared at the shadows on the ground and above their heads every day, through Baifeng's explanation, instantly understood everything they hadn't figured out, and all their difficult problems were also completely understood.

"Baifeng, since you know everything, why don't you do this yourself, instead of letting your subordinates do it, and having to cooperate with us?" Xuanyuan was very puzzled by this.

Baifeng spread his hands: "I only know the general principles, but how it changes every day, the movement of the sun every day, every season, as well as the moon and the stars, is actually much more complex than this."

"To thoroughly figure it out, we must have enough manpower, then observe and record day and night without stopping, and spend many years to be able to supplement everything I have here clearly."

"I can indeed make a rough calendar myself, but I can only calculate it through the movement of the sun, averaging the sun's journey of three hundred and sixty-five days, and taking the Summer Solstice and Winter Solstice days that we know as two nodes to split the whole year."

"But this obviously won't work. If we don't consider the moon, it won't be accurate enough. My calendar won't be used for many years before it deviates significantly, and it cannot achieve the purpose I want to use it for—to regulate farming time. If we want to use the timing of Heaven to direct agriculture, then the movements of the sun and the moon must all be taken into account."

"Moreover, even if we make a calendar now, it is not perfect and still needs to be calculated further, because the moon's movement time is not exactly thirty days, and the sun's journey for a year is three hundred and sixty-five days."

"But it is not exactly three hundred and sixty-five days (there were errors in previous chapters, which have been corrected; I mistakenly wrote the number of days in a solar year as the number of days in an agricultural calendar. The time of a solar year is fixed; the perfection in later generations was to narrow the range of the remainder of the solar year). It might be a few hours more or a few hours less. I don't know; you need to continue to observe."

"Even if you treat the moon as thirty days from empty to full, three hundred and sixty-five cannot be divided evenly; there will be a little left over. Therefore, after a few years, we need to add a month to average out these extra days. This month is called a Leap Month."

"What's more, you have already observed that the moon from full to empty, which is what you call a Synodic Month, is about fourteen days and a little more, and from full moon to waning moon is another fourteen days and a little more. It is not exactly thirty days at all. So, after a year, there is a relatively large gap between the time the sun moves and the time the moon moves. If you are not careful and don't spend enough time, you won't be able to calculate it."

"But now, don't we already have the rough data? We have the number of days for the moon's movement and the number of days for the sun's movement. We put these together, eh! Isn't the calendar out?"

Xuanyuan's eyes lit up, and he asked everyone present: "Did you understand? Can you make it now?"

The eyes of the others were even brighter than Xuanyuan's. Now they felt they had no more questions and could calculate the calendar right away.

Baifeng waved his hand: "What are you waiting for? Calculate! Sun Observation Group, you don't need to look at the data, right? With just that little bit of data, you have it clearly memorized in your heads, right?"

"King! No problem, we will calculate it now!"

The Moon Observation Group and the Sun Observation Group immediately combined their tables to discuss, while Xuanyuan pulled Baifeng aside and asked: "Baifeng, how on earth do you know these things? This doesn't look like something someone of your age could know. You also said you didn't have that much time to look up at the sky, and what's more, what you know seems to be more than what they have observed for several years."

"Also, why is the Earth under our feet like an egg instead of flat? If it's like an egg, why can't I see any curve? Wouldn't the people below us fall off?"

Baifeng wanted to cover his head. This was why he didn't want to tell people of this era about the Earth theory, because it would lead to a series of questions, and he would have to explain what gravity was. Even in later generations when science and culture were so developed, the Flat Earth theory was still popular; how was he supposed to explain it?

Baifeng did not intend to explain it in too much detail, so he picked up a pen, showed it to Xuanyuan, and then let go, letting it fall onto the table.

"Baifeng, what do you mean?"

Baifeng sighed: "You saw it too. A pen cannot fall into the sky; it can only fall to the ground. Don't you think people and things in other places are the same? We are standing on an egg, but that doesn't mean we are on the very top of the egg. In all places, for all things, it is impossible to fall 'up'; they can only fall 'down'."

"As for how I know, I said, I am the Son of the Heavenly God. All knowledge comes from the Heavenly God, but you don't believe it."

After saying this, Baifeng ignored Xuanyuan. Xuanyuan also seemed to have some realization, his eyes fixed on that pen.

"King, King!" The officials of Huaxia called out to Baifeng loudly.

"How is it?"

What was handed to Baifeng was a piece of paper, on which twelve months had been clearly divided from one to twelve. Each month was thirty days, but at the end, there was an extra thirteen, which only had eleven days.

Simple calculation problems could not stump them. After they simply communicated with each other for a few sentences, they wrote out the draft of this calendar.

Ta of the Sun Observation Group said directly: "King, how should these last eleven days be handled? Is the Leap Month only eleven days? Why not put them into other months? That way, only one month would have thirty days, and the other months would all have thirty-one days, which would be easier to remember."

Baifeng hadn't even introduced it yet, but Xihe of the Moon Observation Group refused: "Why? Wouldn't our moon observation be in vain then? Thirty-one days do not conform to the waxing and waning laws of the moon!"