What is an armillary sphere?

The armillary sphere is a general term for armillary sphere and elephant. The armillary sphere is an instrument for measuring celestial sphere coordinates, and the armillary sphere is an instrument used to demonstrate celestial phenomena in ancient times. The inventor of the armillary sphere was Luo in the Han and Western Han Dynasties, and Zhang Heng, a great scientist in the Han and Eastern Han Dynasties, improved it.

The earliest existing armillary sphere in China was made in Ming Dynasty and displayed at Nanjing Purple Mountain Observatory.

Theoretical background

Zhang Heng improved the armillary sphere.

Huntian theory is an important theory of the universe in ancient China, which holds that "Huntian is like a chicken, celestial bodies are round like an egg ball, and rehmannia is like a chicken". The sky is full of water, supported by air, and the earth floats on the water. Hunyi and Hunxiang are instruments that embody Huntian theory, namely "materialization" and "Huntian theory".

Composition structure

Detailed structure of armillary sphere

The armillary sphere is the general term for elephants and armillary spheres.

celestial globe

The structure of an elephant is a big sphere with stars, equator, ecliptic, hidden circle and visible circle. , similar to a celestial globe.

armillary sphere

The armillary sphere is an observation instrument with a peephole, also known as a telescope, which is used to measure the equatorial coordinates of faint, dark and midnight stars and celestial bodies, as well as the longitude and horizon coordinates of celestial bodies. The armillary sphere consists of an early four-way instrument and an equatorial ring. From Han Dynasty to Northern Song Dynasty, the armillary sphere added ecliptic ring, horizon ring, meridian ring, Liuhe instrument, white ring, inner equatorial ring and right ascension ring. In the Northern Song Dynasty, Shen Kuo cancelled the White Road Ring and changed the position of some rings. In the Yuan Dynasty, Guo Shoujing cancelled the ecliptic ring and divided the original armillary sphere into two independent instruments: simple instrument and vertical instrument.

Ethnicity

China has a long history of astronomy. By the Han dynasty, there had been schools of thought such as covering the sky, announcing the night and turbid the sky. Gaitian said that the sky is like a lid, the center of the lid is the North Pole, the lid turns left, and the sun, moon and stars turn right. Michelle Ye said that the sky is amorphous, and the sun, moon and stars "naturally float in the void" and are not attached to "celestial bodies". Huntian said that the sky is like an eggshell and the ground is like an egg yolk. Heaven and earth stand by and watch, carrying water and moving.

Michelle Ye's theory was later lost, and another day it went hand in hand with Huntian to compete with each other. The more scientific Huntian theory gradually gained the upper hand. At the same time, instruments for observing astronomical phenomena are constantly appearing. For example, Luo made an armillary sphere in the period of Emperor Wu of Han Dynasty, Geng Shouchang made an armillary sphere in the period of Emperor Wu of Han Dynasty, and Jia Kui, a teacher of Cui Yuan in the period of Emperor Wu of Han Dynasty, made ecliptic bronzes.

Zhang Heng inherited and developed the achievements of predecessors. After Ren Taishi ordered, he worked harder to "study Yin and Yang" and finally "perfected the meaning of Xuan Ji". In the fourth year of Yuan Dynasty (A.D. 1 17), Zhang Heng made a bronze armillary sphere with unprecedented achievements. The main body of the armillary sphere is a circle, and there are several layers that can run. The circumference of the outermost layer is 10 foot, 4 feet and 6 inches. Each floor is engraved with internal and external rules, such as south, north, yellow, equator, 24 solar terms and 28 solar terms, as well as "middle" and "outer" stars, the sun, the moon and the five latitudes. There are two leaking pots attached to the instrument, and there are holes in the bottom of the pot. The water drops push the circle and the circle rotates slowly according to the scale. As a result, all kinds of celestial phenomena are displayed in front of people. This instrument is placed in the secret room of the hall of GV. In the evening, the indoor staff reported the sky phenomena at a certain moment to the sky watcher on the platform in time, and the result was that the instrument was completely consistent with the sky.

There is a jade shovel (dragon) on each side of the bronze musical instrument, which spits water into the pot, with night on the left and sun on the right. There are gold and bronze immortals and Xu disciples on the pot respectively. "They all hold arrows in their left hands and carve arrows in their right hands, so different days will be sooner or later." Even more amazing: there are Swiss wheels and pods with built-in mechanical devices under the steps connected to the two pots. Driven by dripping water, they keep rotating and opening and closing according to the change of the moon, indicating the new moon, moon, string, sunset and other dates, just like an activity calendar. It can be seen that this armillary sphere and its accessories have many similarities with modern fake celestial bodies. One year before the birth of this musical instrument, Zhang Heng first made a model with bamboo sticks, called "Little Soul", and made a series of experiments and corrections before casting it into a big musical instrument. The armillary sphere is the crystallization of Zhang Heng's blood and sweat. He went on to write two explanations, namely "Illustration of the Amazonian Instrument" and "Annotation of the Water Leakage Turning to the Amazonian Instrument", and then wrote a book "Lingxian County" and a book "Lingxian County Map".