Manuscript data flies into space

It took mankind a long time to realize that the earth under our feet is a sphere. Where should the globe of the earth be placed in the universe? At first people put it at the center of the universe. Later, a man named Parado Xi found that some stars in the sky were moving-people called them planets, and correspondingly, the static stars were called stars. So people say that the moon, the sun, the planets and all the stars in the sky are in circular orbits around the earth. Ptolemy was the first to determine the relationship between the earth and the planets by mathematical methods, and made a quantitative description of the universe in the eyes of the ancient Greeks. This picture later became the theoretical basis of Christian theology. It was not until 1543 that Copernicus published the theory of celestial motion that the earth was moved away from the center of the universe. In Copernicus's system, the earth is no longer the center of the universe, but revolves around the sun in a circular orbit like other planets.

/kloc-before the 0 th/7 th century, people always observed elephants with the naked eye and studied celestial bodies with some simple measuring instruments, mainly the sun, the moon and the five planets visible to the naked eye. China people used the familiar five elements of fire, water and earth in Jin Mu, and the ancient Greeks and Romans named these planets after their familiar gods. 16 10 years, Galileo invented the astronomical telescope, which broadened people's horizons and saw a new picture of the universe invisible to the naked eye.

From18th century to the first half of19th century, modern astronomy has made great progress. During this period, a complete motion theory of planets, the earth and comets was established, some new planets, satellites of planets and asteroids were discovered, and the observation field was extended from the solar system to other star systems in the Milky Way. /kloc-in the second half of the 9th century, astronomers introduced some new theories and methods in physics at that time into the study of celestial bodies, founded astrophysics, and began the stage of modern astronomy.

After entering the 20th century, great progress has been made in both astrophysical theory and celestial observation methods. In the field of traditional optical astronomy, with the appearance of reflective astronomical telescope, the aperture of astronomical telescope is increasing, which changes the limitations of refractive astronomical telescope in19th century. In 1908, 1.5m mirror, 19 18, 2.5m mirror, 1948, 6m mirror, 1976 and 1993.