What is the Great Calendar? What dynasty is the Great Yan calendar?

The Great Yan Calendar", Tang Xuanzong Kaiyuan 15 years (AD 727) monk and his line (683-727), after Zhang Shuo (667-730) and Chen Xuanjing collated into a document, Kaiyuan 17 years (AD 729) promulgated, used to Tianbao ten years (AD 751). It was introduced to Japan in the twenty-first year of Kaiyuan (733 AD) and has been used in Japan for nearly a hundred years. The structure of the Great Calendar is rigorous and well-organized, with a total of seven calendars and specific calculation methods.

There are also 12 articles on the calendar (including three examples), which talk about the theoretical problems of the calendar, which is written in one line of the "Great Yan Calendar", commonly known as the "Great Yan Calendar". The formulation of the Great Calendar began with the manufacture of instruments, and the basic astronomical data were determined through actual observations, which was a scientific method. After the formulation of the Great Calendar, we have a correct and comprehensive understanding of the uneven movement of the sun and the moon.

Through actual observation, the fallacy of "a thousand miles apart" that has been circulating for thousands of years has been dispelled. In terms of calculation methods, the formula of the unequal interval quadratic difference interpolation method created in the "Great Calendar Calendar" is another improvement compared with the "Imperial Calendar".

The Great Calendar was made by a group of masters, and played a small guiding role in China's future agricultural production.

This paragraph of the Great Calendar.

It is also known as the "Kaiyuan Great Calendar". In the seventeenth year of the Tang Dynasty (729 AD), the calendar of twenty-nine years was implemented. One line. Because the regiment is in the great calendar.

The legislation is named after the number of "Yi" elephants. A line of measurement of the latitude of each place, south to Jiaozhou to the north of Tiele, and step nine sundials, set the eclipse score of each place, and re-measure to see the movement of stars. Fifteen years later.

It is divided into seven chapters, including the Peaceful Hope, the Seventy-two Signs, the daily position and movement of the Sun and the Moon, the daily astrological signs and the time of day and night, the solar eclipse, the lunar eclipse, and the positions of the five planets.

This paragraph is formatted as a calendar.

Later generations of calendarists followed suit, using its format to compile calendars. The New Tang Dynasty Book. Almanac I:

The Tang Dynasty began more than 290 years, and the calendar changed eight times. At the beginning, it was called Wuyin Yuan Calendar, Linde Jiazi Yuan Calendar, and Kaiyuan Dayan Calendar. "And "Chronicles IIIA":

In the ninth year of Kaiyuan, the eclipse of the Lin De calendar was ineffective, and the edict monk and his party made a new calendar, pushing the large number of techniques to respond to it. Fifteen years, the grass was completed and a line was completed, Zhao Tejin Zhang said and the official Chen Xuanjing and other times for the "calendar" seven articles, "Brief examples" one, "calendar" ten articles, Xuanzong Gu visitors called the system. Chen Zunfei, History of Chinese Astronomy, Part VI, Chapter 5:

On the basis of the observation data of Liang Lingzan and Nangong Shuo, the party compiled the Great Yan Calendar; At that time, it was rare to make up a calendar after such full preparation, so the Great Yan Calendar was called the crown of the Tang calendar and was listed as a good calendar, which can be said to be a matter of course. ”

This is the calendar system.

The calendar system is thorough, reflecting the laws of the sun's movement more accurately, and the system is thorough, indicating the maturity of the ancient Chinese calendar system. Yi Yi is also the founder of the world's scientific method to measure the length of the earth's meridian. The party realized from the actual measurement that the understanding obtained in a small and limited space cannot be arbitrarily deduced to a large or even infinite space, which is a great progress in the history of scientific thought in China.

This section of the regiment is a great evolution.

In the "Qiankun Spectrum", the Tuanzheng Dayan calendar is based on an eight-year compilation cycle. It is derived from "the number of the Great Yan is fifty, and its use is nine out of forty".

Cycle for the preparation of this paragraph.

The number of Dayan is 50 + its use 49 = 99 (lunar months) = 8 return years. Tuanzheng Dayan calendar: three years old one leap, five years old two leap, eight years old three leap.

Lunar year 354 days 8 years + 30 days 3 leap = 2922 days. The current solar calendar: one leap in four years, two leaps in eight years.

The solar year is 365 days, 8 years + 1 day, 2 leap years = 2922 days. See "Nine out of forty."

Open categories: Astronomy, Calendar, One line.

The Great Yan Calendar is an advanced calendar of the Tang Dynasty. Initiated by one line. The compilation began in the thirteenth year of Xuanzong's reign, that is, in 725 A.D., and the first draft was completed in the fifteenth year of Kaiyuan.

Unfortunately, one line passed away due to illness just after the first draft was completed. After the death of his line, his heirs, Zhongshu Ling, Zhang Yue and Chen Xuanjing, the official of the calendar, inherited the Zhi, continued to review the "Great Yan Calendar", and promulgated it in the seventeenth year of the Kaiyuan Dynasty, for a total of 32 years.

The Great Calendar is a highly systematic almanac, with a total of 7 almanacs, as well as 10 almanacs summarizing historical experiences and expressing personal opinions. The 7 chapters of the almanac include the daily positions and movements of the Sun and the Moon, the daily astrological signs and diurnal moments observed each day, the solar and lunar eclipses, and the positions of the five planets. The structure of the arrangement is rigorous and well-organized, and it is a model for later people to rearrange the calendar.

The concept of "fixed qi" was first put forward in the Great Calendar and used it to compile a table of solar motion, that is, the degree of the sun in a return year, divided into 24 equal parts, and each equinox of the sun is a solar term, and the time between the two solar terms is unequal. In order to deal with this problem, Yiyi also invented the unequally spaced quadratic difference interpolation method. In the calculation of the correction of the unevenness of the motion of the five planets, the ** with the property of sinusoidal function and the approximate interpolation formula with cubic difference are used.

Many of the data in the calendar are both observations of the time and the results of predecessors, so it is more precise than other calendars existing in the Tang Dynasty, and it is a relatively advanced calendar.

The Great Yan Calendar is a type of calendar used during the Tang Dynasty. During the reign of Emperor Zhongzong of the Tang Dynasty (705-710), a group of scholars under the leadership of Prime Minister Li Xian devised this calendar to solve the problem that the average length of the old Tang calendar year was inaccurate. The original name of the Great Yan Calendar was "Kaiyuan Calendar" Qing Fool Qing, but because there was already a calendar with the same name in the Kaiyuan Dynasty, it was later renamed the Great Yan Calendar.

The Great Lunar Calendar uses the leap month method to adjust the flat leap month to ensure that its average length is accurate. The division of the months is also similar to the current Gregorian calendar, with a month of 29 or 30 days in length. In addition, the Maha Taka Derivative Calendar also uses the century leap method, i.e., there are only 97 leap years every 400 years, which is more accurate than the current Gregorian calendar, which is a leap of 1 day every 4 years.

The Great Calendar is highly accurate and widely used, and occupies an important position in the history of the Tang Dynasty and for a long period of time. However, with the change of times, the Great Calendar has also been replaced by more precise calendars, such as the "dot calendar" of the Qing Dynasty. Today, the Gregorian calendar we practice is based on the "World Almanac" developed by the International Astronomical Union, which has become a universal calendar.

The historical calendar has an important impact on the development of human society and cultural exchanges, which not only reflects human cognition and grasp of time, but also promotes the development of human society in agriculture, religion and other aspects. Now, with the continuous progress of science and technology, we have more and more accurate control of time, and we also have more accurate calendars and timekeeping methods. <>

What are the characteristics of China's ancient calendar "Great Yan Calendar"?

Hello, dear. "The Great Yan Calendar" is a Tang Dynasty calendar stupid code, written by Tang Dynasty monks. It inherited the advantages and advantages of China's ancient astronomy, and corrected the deficiencies and shortcomings, so it made great achievements.

It had a great influence on the compilation of the calendar for later generations. The most outstanding performance of the "Great Evolutionary Calendar" is that it correctly grasps the speed and change of the sun's movement on the ecliptic.

In 724 A.D., a new calendar began to be compiled. He adopted some calculations from Indian astronomers to make the data more accurate. Three years later, the draft of the new calendar was completed, and it was named the Great Calendar.