Geocentric and heliocentric theories

The geocentric theory holds that the Earth is the center of the universe and other celestial bodies orbit around it. Due to the backwardness of ancient cosmic observation, whether in the East or the West, geocentrism is the mainstream theory that describes the structure and operation of the universe. Ancient observers had not yet been able to discover planets farther away from the Sun than Saturn, so in the geocentric model, only the Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn orbit the Earth. The heliocentric theory holds that the sun is the center of the universe, and the Earth and other celestial bodies orbit around the sun. The proposal of heliocentric theory fundamentally changed astronomy, broke through the shackles of traditional theological views, and promoted the continuous development of natural sciences.

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

The geocentric theory, as a concept, was formed during the ancient Greek period. The Milesian school first formed its theoretical prototype, Eudoxus developed Plato's concentric sphere theory centered on the Earth, and Calyphus and Aristotle further supplemented and improved it. Apollonius' "Ben Wheel Equal Wheel" model proposes that celestial bodies move around the Earth but not on an orbit centered on the Earth, but on their respective Ben wheels, with the center of the Ben wheel being on the equal wheel centered on the Earth, thus solving the problem of inconsistency between previous models and observational results. In the 2nd century AD, Ptolemy explicitly proposed the geocentric universe system in his book "Almagest", and his system could predict the positions of future planets, which roughly matched the observational results. Although this theory was later deemed incorrect, it was the first to propose that the Earth is "round", distinguish between planets and stars, and design the "Ben Wheel Equal Wheel" model, which was the world's first complete line.