Full-time astronomical institutions and their daily work
Since Tianxue is monopolized by Heaven Emperor, natural Tianxue institutions and its direct symbol observatory (similar to the modern observatory, of course, with different purposes) are also monopolized by the royal family, and it is impossible to set up other local governments or individuals, otherwise it would be an act of "committing an offence and insurrection", which is illegal in the present words. However, in the ancient history of China, one exception can be found, that is, Zhang Zixin in the Northern Qi Dynasty. He may have established a small observatory on the island during the long-term war in the Central Plains and made important achievements. This is perhaps the only example in ancient China that can be compared with western private observatories. The changes and evolution of the names of Tianxue institutions and the official names of the main responsible persons in the past dynasties are as follows:
Qin Taishiling
Tai Shi Gong Tai Shi Ling in the Western Han Dynasty
Taishiling in Eastern Han Dynasty
Taishi Bureau of Wei, Jin, Southern and Northern Dynasties; Court historian
Sui Taishi Cao Taishi supervisor; Taishiling
Tang Taishi Bureau is in a daze, and the prison is in a daze. Taishi Bureau ordered the prison to be stunned, Taishi prison and Tiantai prison. 824 people
Institute of Astronomy, Taishi Museum; Song Sitian Jian; Department Order of Tian Jian Taishi Bureau
Liao Si Tian Jian; Taishiling
Golden roof; Power regulating supervisor
Si Yuan returned to Sitai History Museum; The history of Imperial College London. 259 people
Qin Ming Tian Jian; Taishi ordered the supervisor to be correct. 4 1-23 people
Qing Qin Tian Jian; Jian Zheng. 154 people
Different from the status of astronomers in modern society, the heads of ancient royal astronomical institutions and their subordinates are government officials; Tianxue institution is a department of the central government, and there are usually no permanent subordinate institutions and personnel at the local level. Sometimes for special observation tasks, temporary personnel will be appointed, except in the Yuan and Ming Dynasties. But the theoretical level of this department has not been too high. At the highest time, it reached about level 3 in the Tang Dynasty, and at the lowest time, it reached about level 5. There are three main sources of personnel in Tianxue institutions: first, hereditary Tianxue officials, second, recruitment from the society, and third, special training by themselves.
The main tasks of astronomical institutions are as follows: first, the observation records of astronomical phenomena, including the determination of the position of stars, are compiled into a catalog or drawn into a star map; Solar eclipse and occultation observation; Apparent motion of planets in the background of stars; Observational records of abnormal astronomical phenomena, including comets, nova, meteors and sunspots. Some of these celestial phenomena should be reported to the emperor selectively. Second, the development and management of sky observation instruments. The third is to revise the calendar, compile the calculation almanac spectrum, and print and distribute it.
Observation means and research-astronomical instruments and classics
The appearance of astronomical instruments is the inevitable result of astronomical quantification. Only by means of astronomical instruments can we measure all kinds of astronomical data accurately and quantitatively. Astronomical instruments in ancient China can be roughly divided into three categories: standard watches, missing engravings and instrument images. Among them, armillary sphere and image instrument are the basic instruments used by ancient soldiers to measure weather and demonstrate astronomical phenomena.
The armillary sphere is an equatorial instrument for measuring the position of celestial bodies. It was made in different dynasties, but it was basically composed of many concentric rings, including peepholes. Measuring the position of celestial bodies is the most important basic work in ancient astronomical affairs, so all previous dynasties have trained soldiers as much as possible. It is still difficult to determine when the armillary sphere was invented. It is clearly recorded in Historical Records that the armillary sphere was made by Luoxia Hong in the Western Han Dynasty. Later, Jia Kui, Zhang Heng and Kong Ting in the Eastern Han Dynasty, Li and his entourage in the Tang Dynasty, and Shen Kuo and Su Song in the Northern Song Dynasty all improved the armillary sphere to varying degrees, making it beneficial to actual observation. Guo Shoujing's simple instrument in Yuan Dynasty was the product of the innovation of armillary sphere.
The manometer is a simple and important astronomical instrument, which consists of a vertical manometer (usually eight feet high) and a horizontal manometer. The main function of a standard watch is to determine the position of the winter solstice, and then determine the length of the tropical year. In addition, we can also determine the direction and solar terms by observing the changes of surface shadows.
Missing carving is an ancient timing tool. Leakage refers to the leaky cauldron for timing, and engraving refers to the division of a day's time unit. It measures the time of day and night by leaky cauldron's floating arrow. The timing method of missing engraving can be divided into two categories: drainage type and water receiving type. Water leakage is an independent timing system, which only depends on the movement of water. The improvement of clepsydra is a technical problem, but ancient astronomers such as Zhang Heng and Shen Kuo all contributed to the improvement of clepsydra. Because in addition to accurate time measurement in daily life, astronomical calendar also needs accurate time measurement system.
The elephant is an instrument used by the ancient celestial globe to demonstrate the Sunday movement of the celestial sphere, similar to the modern celestial globe. The basic structure is a sphere with stars, ecliptic and equator. Han Geng Shouchang, Zhang Heng, Wu and Wang Fan of the Three Kingdoms have all made mechanical rotating elephants, the most famous of which are Tang and his party and Liang Lingzan's Kaiyuan Water Transport Huntian, Zhang Sixun's Taiping Hunyi in the Northern Song Dynasty and Su Song's Hunyi Elephant (now commonly known as the water transport instrument platform). Su Song once wrote a manual about the structure, shape and size of the whole musical instrument stage, the new method of musical instruments.
The most systematic, complete and well-documented ancient books on Tianxue in China should be the first to introduce three records of Tianxue in the official system of past dynasties: the record of Fa Li, the record of Tianwen and the record of Five Elements. The names of these three records have changed slightly in a few official histories, but their contents are still consistent with the tradition. Five-element annals specifically record the disaster and auspicious situation in this dynasty, which is a summary of the documents reported by various places. Falizhi is a collection of documents about the laws and calendars of this dynasty. Astronomical records are astronomical events, astronomical records and corresponding astrological statements that occurred in this dynasty. In addition, there are important works on astrology, such as Kaiyuan Zhan Jing. Official large-scale astronomical works, such as Chongzhen almanac, and folk works, such as Zhu Ming's "Shengshou Wanli" again.
Four Theoretical Foundations —— Cosmology and Heaven Thought
"Huai Nan Zi Yuan" notes: "The four directions say" Yu "from top to bottom, and" Zhou "from ancient times to the present, which means heaven and earth". The universe is generally considered as the general name of all things in the world. Cosmology studies the structure and evolution of the universe from a holistic perspective. In ancient China, there were three theories about the structure of the universe, namely, Gaitian theory, Huntian theory and Michelle Ye theory, as well as Xin Tian theory, Qiutian theory and An Tian theory.
Huntian theory holds that heaven and earth are egg-shaped, with the earth in the center and the sky around. I don't know when and who first put forward the theory of Huntian. But as a theory of the universe, its emergence and development are closely related to a practical astronomical instrument-the armillary sphere. The clear theory of the armillary sphere contained in Historical Records was not put forward until Zhang Heng made the armillary sphere and annotated it in the Eastern Han Dynasty. Zhang Heng's cosmology has been quoted and developed by later astronomers for many times, and it has become the cosmology recognized and followed by most astronomers in ancient China. Ancient astrologers in China made astronomical observation and calendar calculation according to the universe model described in the Notes of the Astrologer. Calendar calculation methods in past dynasties have often been improved, but the basic model is still rarely changed.
Gaitian theory is a cosmic theory that appeared earlier than Huntian theory, and its origin and development process can be divided into two stages. The first stage is the original concrete metaphor of the theory of heaven and earth, without further quantitative description of the structure of heaven and earth; In the second stage, a complete quantitative structure of heaven and earth is put forward based on Zhou Bi suan Jing. The basic assumption is that heaven and earth are parallel, 80 thousand miles apart. Gaitian theorists use this to explain the structure of heaven and earth and the movement of celestial bodies, and make quantitative description and calculation.
Michelle Ye said that the sky is infinite and empty, and the stars are suspended in the emptiness and run freely. There are only two records about Michelle Ye's theory in the history books, and one of them accuses it of being "unrepeatable". This view is quite similar to modern cosmology, so it often developed properly and became the most advanced cosmology in ancient China. However, Michelle Ye said that the sun, the moon and the stars all run freely, so there is no way to talk about their running laws. This exaggeration of the free movement of celestial bodies makes Michelle Ye's theory not a quantitative description of the structure of heaven and earth, so strictly speaking, it cannot be called the theory of the universe.
In addition to the above three schools, there are also the "Xin Tian Theory" where Wu Taichang and Yao Xin lived in the Three Kingdoms, the "Dome Field Theory" by Yu Song in the Eastern Jin Dynasty and the "An Tian Theory" in the Jin Dynasty, which can not be called a strict theory of the universe and have no influence on future generations. Only Huntian Theory and Gaitian Theory are China's real universe theories in ancient times. Both theories have their own reasonable components and have not been completely abandoned.
China's ancient theories of "covering the sky" and "Huntian", standard watches, armillary sphere and other instruments, and the operation rules of astronomical calendars all serve a practical purpose-to serve the kingship. However, what endows this practical purpose with mystery, solemnity and majesty, and makes everyone believe in its effectiveness, is the ancient thought of heaven-the unity of heaven and man. The "sky" here refers to the whole nature. In the eyes of ancient China people, it is not an object that can be recognized without will and emotion as mentioned in the "objective hypothesis" of modern science, but a huge and mysterious life with will and emotion, which can not be fully understood, and can only conform to its Tao and live in harmony with it. It is manifested in two different levels: the connection between heaven and earth and the correspondence between heaven and earth.
Calendar has made five major mathematical astronomy achievements.
The main research contents of ancient calendars in China are the laws of motion of the sun, the moon and the five planets. As far as this research content is concerned, it is appropriate to call China's ancient calendar China's ancient mathematical astronomy. There are nearly 100 kinds of historical records before and after the ancient calendar in China, among which more than 50 kinds are officially promulgated. Each calendar has inherited and changed in its specific contents and calendar management methods, which lasted for more than two thousand years and was described endlessly. It's amazing. Generally speaking, the central topic of China's ancient calendar can be summarized into two aspects: reason and data. Principle refers to the reflection of the movement law of the sun, the moon and the five stars in the calendar; Data refers to the numerical description of the movements of the sun, the moon and the five stars in the calendar. The sparseness and secrecy of the calendar are mainly manifested in these two aspects.
According to the principles and materials, the ancient calendar of China can be roughly divided into three stages in chronological order: (1) calendars of Han, Wei, Jin, Southern and Northern Dynasties; (2) Sui, Tang and Song calendars; (3) Yuan and Ming calendars.
Legend has it that there were so-called pre-Qin ancient six calendars before the Han Dynasty, but even the ancients had long doubted its authenticity. Taichu calendar edited by Emperor Wu of the Han Dynasty is the first calendar recorded in ancient China, but it has never been handed down. The Three Calendars written by Liu Xin at the end of the Western Han Dynasty is the first fully preserved calendar, but scholars think it is almost a copy of taichu calendar. The calendar of the later Han Dynasty was revised repeatedly, but there was no substantial change. It was not until Liu Hong's "Dry Image Calendar" that the unevenness of the lunar surface motion was introduced, which was a great progress. This calendar was not promulgated, and its advanced method was not adopted until the Wei and Jin Dynasties. Li Yuanjia by He Chengtian in the Southern Dynasties improved the measured data. Zu Chongzhi's Da Ming Calendar tried to improve the accuracy of the calendar by changing leap weeks and measuring the winter solstice, but due to political reasons, its method failed to be implemented.
According to He Chengtian's method, Sui's "opening the imperial calendar" only slightly increased the loss. Liu Zhuo's "Imperial Calendar" is based on the annual apparent motion of the sun and the unevenness of planetary motion discovered by Zhang Zixin in the Northern Qi Dynasty. Adopt a fixed new moon and precession; Advanced mathematical methods are also used to solve calculation problems. The application of all these advanced principles and methods has made Huang a milestone in history. Also for political reasons, its laws cannot be implemented. But people call it accuracy. Although Five Tones Calendar and Li Linde Calendar have been used for some time, their achievements are not beyond the scope of Huang Ji Calendar. Until the line of Dayan calendar, there were great innovations in the knowledge, measurement and calculation skills of celestial bodies, making Dayan calendar the best calendar in the history of ancient China. Nineteen kinds of calendars were published in the Song Dynasty, but there was no major breakthrough.
After the Dayan calendar, the chronograph calendar of Guo Shoujing and others in Yuan Dynasty became another peak in the history of China. After hundreds of years of efforts, the laws of celestial movement reflected by calendars, that is, the basic principles of calendar management, have been roughly mastered by ancient astronomers. If we want to improve the calendar, we must work hard on data and its processing methods, and the "chronograph calendar" is a model of success in this regard. Its basic data are all based on actual measurement, which breaks the old habit of managing calendars in ancient times and creates the source of new laws in later generations. The Ming dynasty followed the big calendar, and its method followed the chronograph calendar.