Use the scraps of wooden planks from repairing the ship as a writing board, and use charcoal as a pen.
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 inclination of the earth 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 ancient mathematical school’s definition of the world and believe that things created by God must be perfect, pi must also be an accurate value.
Some people oppose it, and some people support it. Calculating the exact value of pi has become a 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 those who can study natural philosophy are mostly theological scholars who eat what they have come to eat.
Those theologians need to use this method to further prove the greatness of the Lord.
However, pi has at least one important purpose, 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 did not have an urgent need in this regard. They did not even have a real city. Even the overcrowded Rossburg was made up of a group of wood and animal skins along the bay. A large "shanty town" has been built.
The weather has been beautiful during this period, and Rurik is very happy that the sun can 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 the rope. Measure with a ruler and record the data on the wooden board.
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.
The 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. A standard one-stika length wooden pole stands and its shadow is astonishingly long. Even so, Rurik Still struggling 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 needs to know most isThe 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.
In this era, December 22nd in 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 direct angle of the sun only changes in dimension by 23°26′ in a quarter of a year, Rurik calculated a very accurate value for the change in the direct angle of the sun every day. 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°. Naturally get local latitude data.
In fact, Rurik has obtained five data in succession, and the errors between them are not large.
All data show that the location of Fort Ross 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 if the maximum error is 64°, Roseburg is not enough to fall into polar night for even one day.
Contrary to what he felt, polar night existed in Roseburg.
So, your own measurements need to continue.
Affected by the existence of the polar night, the east will only glow slightly red 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 not possible 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 the 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 Autumn returns triumphantly with a batch of rye and wheat.
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 maintain a healthy population.Stablize.
The planting and harvesting of food are closely related to seasonal changes. A big country must set its own set of calendars.
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 is surveyed and compiled by the state, and the subsequent revision rights also belong to the state, because ordinary people have almost no knowledge of astronomy.
When Rome entered the empire, it particularly needed 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 wall of Hadrian's stone.
The forest areas of 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.
Western Rome was destroyed, and Eastern Rome once inherited the territory of Western Rome. 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.
But 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.
The Julian calendar year is a little shorter than the Earth's revolution period. After eight hundred years of accumulation, the calendar error has actually reached six days!
So 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 has always been able to accurately predict which day the sun will not rise, and that day is a tribal tradition. of Hanukkah. 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 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 of geographical knowledge, 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.
Perhaps, when he was busy, Vilia understood everything many years ago?