What did the ancients in China discover by observing the stars?

China's astronomical research reached a new peak in the Song and Yuan Dynasties.

The astronomical achievements of the Song Dynasty are second to none in the history of our country. From 10 10 to106, under the official auspices, * * * made five large-scale star observations, the most famous of which was the fourth observation, because the observation results also caused a sensation in the world.

From 1078 to 1085, the government of the Northern Song Dynasty organized the fourth large-scale observation of stellar phenomena. A man named Huang Shang drew a star map according to the observation results, and gave it to the then Prince Zhao Kuo, who collected the star map. This is the famous original map of Huang Shang. Zhao Kuo likes this carefully drawn astronomical map very much. Jingkang crossed the south, and this precious astronomical map also spread to the south of the Yangtze River. Since the middle of13rd century, a stone tablet has been erected in front of the Confucian Temple in Suzhou, a picturesque historical city in the south of the Yangtze River. After that, the Southern Song Dynasty perished and the Yuan and Ming Dynasties alternated. Hundreds of years have passed, and no one pays attention to this ancient stone tablet. This ancient stone tablet is about 2 meters high and 1 meter wide. It is engraved with a big disc. There are many dots on the disk and some strange words connected by zigzag lines. This is an astronomical image carved by a man named Wang Zhihe according to the original drawing drawn by Huang Shang around A.D. 1247. On this world-famous astronomical map of Suzhou stone carvings, the result of the fourth large-scale astronomical observation in the Northern Song Dynasty-1430 stars is engraved. It is a treasure in the history of astronomy in China and even in the world.

The most famous astronomer in Song and Yuan Dynasties was Guo Shoujing in Yuan Dynasty. He likes reading books and observing various natural phenomena since he was a child, and he is particularly interested in astronomy. He also made some earth instruments himself, such as an armillary sphere made of bamboo sticks, to observe the astronomical phenomena, which laid the foundation for later invention and creation of astronomical instruments.

In A.D. 1276, the Yuan government ordered the revision of the calendar, and Guo Shoujing participated in this work. Based on the scientific attitude of seeking truth from facts, he proposed to conduct a large-scale observation of astronomical phenomena before revising the calendar, and the official adopted his suggestion. This large-scale astronomical observation activity involving many people increased the number of stars recorded in the history of Arabic studies in China from 1430 to more than 2,500, and the observation results were also made into star maps. Unfortunately, this map has not been preserved.

In astronomical observation, in order to improve the accuracy, Guo Shoujing has made 13 astronomical instruments such as simple instrument, altimeter and inverted instrument within three years. For on-the-spot observation, he also created a set of portable astronomical instruments, and made five kinds of maps, such as altimeter variable distance map and guide cover map, for cross-reference with the instruments.

The simple instrument invented by Guo Shoujing is a bold innovation of armillary sphere. The armillary sphere is the main astronomical instrument used to measure the positions of the sun, moon and stars in ancient times. But the structure is complex, the rotation is inflexible, and there are many rings, which cover some stars and are not conducive to observation. The simple instrument has the same function as the armillary sphere, but its structure is simple and its calibration is accurate. In order to rotate smoothly, ball bearings were installed, which was nearly 200 years earlier than the application of ball bearings in Europe. The astronomical instruments made by Guo Shoujing are more exquisite and accurate than those made by previous people. In the early years of Qing Dynasty, Tang Ruowang, a western missionary, came to China and was amazed at the astronomical instruments invented by Guo Shoujing. He called Guo Shoujing "Tycho of China". Tycho was a famous European astronomer in the16th century. Also make many astronomical instruments. But he was more than 300 years behind Guo Shoujing.

Using the data of this observation, it took Guo Shoujing more than two years to compile a new calendar-service calendar. In the past, the mantissa less than one day in the calendar was mostly expressed by fractions, which was very complicated to calculate. However, Guo Shoujing's "chronograph" was changed to decimal, and he calculated that a year is 365.2425 days, only "seconds" away from period of revolution, which is the same as the Gregorian calendar in the world today. The calendar of timing was promulgated in 1280, 302 years earlier than the current Gregorian calendar.

There are 14 kinds of astronomical calendar works in Guo Shoujing, with volume 105. Among the ancient astronomers, he is the richest one.

From the Spring and Autumn Period in the 6th century BC to the year 2000 in the 5th century A.D./KLOC-0, China has always been in the leading position in the whole field of science and technology, whether it is the theoretical natural science of mathematics, astronomy, physics or the invention and creation of applied technology. The main reason is that scientists in ancient China generally enjoyed freedom of thought. From the Spring and Autumn Period and the Warring States Period to the Song and Yuan Dynasties, China never formed the theological rule of the integration of politics and religion like Islam and Christianity. Therefore, since the pre-Qin period, the developed natural sciences and various academic schools have never been seriously damaged as in ancient Greece and the Middle Ages. This is the most important condition for scientific development.