Use scraps of planks from repairing ships as writing boards and charcoal as pens.
Rurik prepared many wooden boards and a large amount of charcoal, and quickly put into measurement with the participation of other tools.
Because he already knows a lot of key data, such as the earth's inclination and the more accurate values of pi. These two data are of extremely great significance to the geographical mapping of the entire earth.
The study of pi actually triggered a mathematical revolution.
Because theologians believe in the definition of the world by ancient mathematical schools and believe that things created by God must be perfect, pi must also be an accurate value.
Some people objected, some supported it, and calculating the exact value of pi became a kind of competition.
But does it mean anything particularly important to calculate the Earth's inclination and pi values?
In today's era, people everywhere don't care about the tilt of the earth at all, or even whether the world is a flat surface or a ball. Because it is already very difficult for them to live, and most of those who can study natural philosophy are theological scholars who eat what they have learned.
It was necessary for theologians to use this method to further prove the greatness of the Lord.
However, pi has at least one important use, which is to more accurately calculate the circumference and diameter of a wheel. This allowed craftsmen to create wheels with unique circumferences that could be mounted on mechanical devices from the Greco-Roman period to help a lord measure the length of his fiefdom or even the distance between two cities.
But for the Vikings, they had no urgent need in this regard. They didn't even have a real city. Even the overcrowded Rossburg was a large "shanty town" built by a group of wood and animal skins along the bay. district".
The weather was beautiful during this time, and Rurik was very happy that the sun could shine on the frozen land here at noon every day.
The temperature was quite cold. In order to get an accurate value, Rurik had to go outdoors from time to time and pay attention to the changes in the length of the sun's shadow. When the shadow became the longest, he immediately took out a rope ruler to measure it and placed a Data is recorded on wooden boards.
In fact, he only needs one value, and then based on today's date, he can calculate the specific value of the latitude line where the sun shines on the earth today.
Time gradually arrived in December of the Julian calendar, and Rurik knew very well that even if the calendar of this era had errors, the winter solstice would definitely fall in this month.
This can be reflected from the length of the sun's shadow. The sun at noon is only slightly above the horizon. The shadow of a standard one-stika length wooden pole is astonishingly long. Even so, Rurik still struggled to make statistics.
According to the simple Pythagorean theorem, he used charcoal as a pen on a wooden board and did some trigonometric calculations to get an angle value, a very sharp acute angle.
What Rurik needed to know most was the direct angle of the sun on the day of measurement.
Theoretically, because the sun shines absolutely directly on the equator on the autumnal equinox, and on the winter solstice, the sun shines absolutely directly on the Tropic of Cancer, which is 23°26′ south latitude. This is a very accurate value.
It is in this era that December 22 of the Julian calendar is the winter solstice, which is not credible.
But Rurik has measured multiple values one after another!
He tentatively set the winter solstice as December 22, and the next step was to enter the formula.
Since the sun's direct angle changes only 23°26′ in dimension over a quarter of a year, Rurik calculated a very precise value for the daily change in the sun's direct angle. By doing this calculation, he calculated that on December 1st, the direct angle had exceeded 17°.
For example, on December 1st, a cold, dry and sunny day, he measured the angle of the sun's shadow on the pole, calculated the direct angle of the sun today, and finally subtracted the two data from 90° to naturally obtain the local latitude data.
In fact, Rurik has obtained five data in succession, and the errors between each other are not large.
All data show that Roseburg's location is around 63° north latitude, with an error of about 1°.
It seems that Rurik's junior high school student-level experiment has been completed. After all, he has not used more of his knowledge and talents.
So he is very satisfied with the mathematical results he has obtained with his dark hands after working hard for many days? No! He was not satisfied.
Because it is only 63° north latitude, even the maximum error of 64° is not enough for Roseburg to fall into polar night for even one day.
Contrary to what he felt, polar nights existed in Roseburg.
Therefore, your own measurements need to continue.
Affected by the existence of polar night, the east will only be slightly reddish on the day of the winter solstice, and the sun seems to be coming out, but in the end it does not appear. If there is haze during those days, the situation for many days will be no different from the polar night.
Obviously, it is impossible to measure the local latitude in Fort Ross by relying on the sun's shadow. If you want to get an accurate result by just measuring, you will obviously have to wait until the summer solstice. It is also called the day when the shadow of the sun becomes the shortest, which is the summer solstice. To get the data on the summer solstice, you must measure for a long time and record the data.
This matter will be a very huge project. Do I want to become the first astronomer of the Ross tribe? !
It is undeniable that measuring the sun's shadow to determine time is also very important to the Rus tribe. After all, they must go to Novgorod, their servant, at the right time to collect an offering, especially in the autumn with a batch of rye. , Wheat returns victoriously.
In ancient times, for any large country, the source of stability for the country was sufficient food.
A huge country means a huge population. Only by growing crops and eating grains can the country maintain a huge population and remain stable.
The planting and harvesting of food are closely related to seasonal changes, and a big country must set its own calendar.
The only things that can be used as effective references when compiling calendars are probably the moon and the sun. In the end, the lunar calendar and the solar calendar were compiled. There are also Mayans who have developed non-mainstream calendars. In addition to the lunisolar calendar, they also have a Venus calendar.
The calendar was surveyed and compiled by the state, and the subsequent revision rights also belonged to the state, because ordinary people had almost no knowledge of astronomy.
When Rome entered the empire, it was particularly in need of Egypt's food production. To a large extent, the increasing demand for food also determined the direction of the empire's expansion. Rome was happy to land and take possession of Britain because its fields had been developed early and it was fertile land. For the safety of the agricultural area, they simply built a Hadrian Stone Wall.
The forest areas in Central and Eastern Europe have long been areas of Slavic tribes. It is because these areas lack agricultural value that they can wander as forest hunters for a long time.
The Western Roman Empire was destroyed, and the Eastern Roman Empire once inherited the territory of the Western Roman Empire. They maintained it for a short period of time and were eventually robbed by the Franks.
The Frankish Kingdom was established on the ruins of Western Rome, and a series of things were completely different from the previous Roman period.
However, the settled barbarians needed to cultivate land to support themselves. They relied heavily on the calendar established by the Romans, but few people thought that the calendar gradually became inaccurate as time went by.
One year of the Julian calendar is a little shorter than the earth's revolution period. After 800 years of accumulation, the calendar error has actually reached six days!
Therefore, the winter solstice marked on the Julian calendar at this time is completely inconsistent with reality.
Of course Rurik knew this, but he just didn't understand what the error in the calendar was.
Do I have to measure the exact summer solstice myself?
No need to!
The clever Rurik suddenly thought of something that made his hair tremble, because over the years, Vilya could always accurately predict the day when the sun would not rise, and that day was the traditional Hanukkah of the tribe. The tribes will revel unbridled, drink and sing, and watch the first ray of sunshine of the new year shine on the frozen sea of the bay.
Vilia, she knows about the winter solstice!
Does she know "heliometry"? Or do you know other measuring techniques? !
She also knows the theory that the world is a ball. Maybe she already knows a lot about geography, but has never revealed it to others?
Could it be that, in her seventies, she is still a classical astronomer? !
The more Rurik thought about it, the more frightened he became. He carefully thought about his measurement work these days. Vilia was a quiet observer. She had been silently watching her series of work.
Maybe, while he was busy, Vilia understood everything many years ago?
