Geocentric theory is a cosmological theory that prevailed in ancient Europe for a long time. It was first put forward by the ancient Greek scholar Odysseus, and was gradually established and perfected by the further development of Aristotle and Ptolemy.

Ptolemy believed that the earth was at rest in the center of the universe. Seen from the earth, there are the moon, mercury, Venus, the sun, Mars, Jupiter and Saturn in turn, orbiting the earth in their respective circular orbits. Among them, the motion of the planet is more complicated than that of the sun and the moon: the planet moves on this circle, and this circle runs around the earth along a uniform wheel. Beyond the sun, moon and planets, there is a celestial sphere inlaid with all the stars-the starry sky. Outside, it is the primitive earth that drives the movement of celestial bodies. The following is a schematic diagram of this theory:

Geocentric theory is the first planetary system model in the world. Although it is wrong to regard the earth as the center of the universe, its historical achievements should not be obliterated. Geocentric theory recognizes that the earth is "spherical" and distinguishes planets from stars, focusing on exploring and revealing the laws of planetary motion, which marks a great progress in human understanding of the universe. The most important achievement of geocentric theory is to calculate the motion of planets by mathematics. Ptolemy also put forward the concept of "track" for the first time and designed a wheel balance model for this wheel. According to this model, people can quantitatively calculate the motion of planets and guess the position of planets, which is an amazing creation. In a certain period of time, according to this model, the astronomical phenomena can be predicted correctly to a certain extent, so it also plays a certain role in production practice.

After all, Ptolemy pieced together the current wheel model in the geocentric theory based on limited observation data. He made the model consistent with the measured results by artificially specifying the current wheel and the size of the wheel and the running speed of the planet. However, in the late Middle Ages, with the continuous improvement of observation instruments, the measurement of planetary position and motion became more and more accurate, and the deviation between the observed actual position of the planet and the calculated results of this model gradually appeared.

Those who believe in geocentric theory do not realize that this is caused by the error of geocentric theory itself, but use the method of adding this round to remedy geocentric theory. At first, this method can barely cope. Later, the number of small wheels increased to more than 80, but the exact position of the planet could not be calculated satisfactorily. This cannot but make people doubt the correctness of geocentric theory. /kloc-in the 6th century, Copernicus finally founded the "Heliocentrism" on the basis of the enthusiasm of ancient Greek ancestors and contemporary scholars for the sun. Since then, geocentric theory has been gradually eliminated.

Heliocentrism: The sun is the center of the universe, and the earth and other planets revolve around the sun. Heliocentrism is also called "Heliocentrism" or "Heliocentrism System". 16th century, after nearly 40 years of hard research, Copernicus, a Polish astronomer, systematically put forward Heliocentrism in his Theory of Celestial Movement published in 1543, based on analyzing a large number of previous data and his own long-term observation. In Ptolemy's geocentric system, every planetary movement contains a one-year cycle, but Ptolemy can't give a reasonable explanation for this. Copernicus believed that the earth is not the center of the universe, but an ordinary planet, and the sun is the center of the universe. The one-year cycle of planetary motion is a reflection of the earth's annual revolution around the sun. Other contents of the Copernican system are:

(1) Mercury, Venus, Mars, Jupiter, Saturn and the Earth all revolve around the sun in uniform circular orbits.

The moon is a satellite of the earth. It orbits the earth once a month in a circular orbit centered on the earth, and at the same time revolves around the sun with the earth.

(3) The earth rotates once a day, but the sky doesn't actually rotate. It is precisely because of the rotation of the earth that the sun, moon and stars rise and set in the west every day.

(4) The distance between the star and the sun is far away, much larger than the distance between the sun and the earth. Copernicus listed the names of many ancient scholars who advocated the rotation of the earth and the revolution of the planets around the sun. He carried forward the thoughts of these scholars, spared no effort in his life, and established the Heliocentrism system with strict scientific argumentation through hard observation and mathematical calculation. Subsequent observations have continuously confirmed and developed this theory.

Limited to the level of scientific development at that time, Heliocentrism of Copernicus also had shortcomings and mistakes, that is:

(1) thinks that the sun is the center of the universe, but in fact the sun is only a central celestial body in the solar system, not the center of the universe;

(2) The old idea that planets move in a uniform circle is followed. In fact, the orbit of the planet is elliptical, and the speed of motion is not constant.

The story of Heliocentrism.

In ancient times, human ancestors stood in the wild desert and looked up at the sun, moon and stars in the sky, generating endless reverie.

Some people say that the sky is carried by a giant god standing on the ground. The theory of "covering the sky" is thus formed: the ground is flat, the sky is round, the middle rises, and the sides droop, just like a large hemispherical tent covering the ground.

Later, it was found in observation that Gai Tian Shuo could not explain the rise and fall of the sun, moon and stars, and only half a spherical shell was added under Gai Tian Shuo. Thus, "Huntington Theory" came into being.

In the 4th century BC, Aristotle founded "geocentric theory". Aristotle believes that the universe is a limited sphere, which is divided into two layers: heaven and earth. The earth is located in the center of the universe, so the sun and the moon revolve around the earth and objects always fall to the ground. There are nine equidistant celestial spheres outside the earth, and each celestial sphere will not move by itself. It is God who drives the celestial sphere of the star and drives all the celestial spheres. The earth where human beings live stands motionless in the center of the universe.

Ptolemy, as the last great astronomer in ancient Greece, completely inherited Aristotle's geocentric theory and expanded Aristotle's nine-level sky to 1 1.

Ptolemy imagined that all the planets move around a small circle, and the center of each circle moves on a circle centered on the earth. He called the circle around the earth "even wheel" and each small circle "current wheel". At the same time, he assumes that the earth is not completely in the center of the even wheel, but at a certain distance, and the even wheel is an eccentric circle. In addition to the above orbits, the sun, moon and planets also orbit the earth once a day with the stars, which makes the calculated results consistent with the measured results and has achieved practical value in navigation.

Ptolemy's geocentric theory caters to Christianity and is used by Christianity to maintain biblical theory. The Bible proclaims that the universe and the earth were created by God and the Lord, the earth is at rest in the center of the universe, the holy land Jerusalem is in the center of the earth, human beings are God's favorite children, and everything in the universe is created by God to meet human needs. ...

Thus, Ptolemy's "geocentric theory" became the Bible, and astronomy became the handmaiden of religion, which lasted until the Copernican era.

Copernicus was born in 1473 in a merchant family in Torun, Poland. When he was 10 years old, the plague took away his father. From then on, Copernicus began to live with his uncle Vukash. /kloc-When he was 0/8 years old, his uncle sent him to Krakow University, where Copernicus, with a keen mind, became very interested in astronomy and mathematics. He delved into mathematics, extensively dabbled in ancient astronomical books, devoted himself to the study of "geocentric theory", made many notes and calculations, began to observe astronomical phenomena with instruments, and began to conceive a new astronomical system in his mind.

Later, Copernicus came to study in Italy and studied at the University of Padua, where the academic atmosphere was very active. Nofara, a professor of astronomy at the university, expressed doubts about "geocentric theory" and thought that the structure of the universe could be expressed by a simpler schema. Under the influence of his thoughts, Copernicus germinated his views on the rotation of the earth and the revolution of the earth and planets around the sun.

After Copernicus returned to Poland, he continued his long-term astronomical observation and research, further confirming that the sun is the center of the universe. Because the forward and backward motion of the planet is an illusion caused by the different periods of the earth and other planets revolving around the sun. On the surface, it seems that the sun goes around the earth, but in fact, the earth goes around the sun with other planets. It's like sitting on a boat, obviously the boat is moving, but we feel the shore is retreating.

Copernicus observed and calculated day and night, and finally broke through many obstacles and founded the "Heliocentrism" with the sun as the center.

Copernicus once wrote a short talk about the main points of his "Heliocentrism" and copied it to some friends. His views immediately attracted the attention of European countries, but he dared not write them all for fear of persecution by the church.

However, Copernicus once said: "The bounden duty of human beings is to explore the truth." Under the strong impulse to explore the truth, he began to write the book "The Operation of Celestial Bodies" with hesitation.

After many twists and turns, this six-volume scientific masterpiece "On the Operation of Celestial Bodies" finally came out with difficulty. At this time, Copernicus's life has come to an end. An hour before he died, he saw the book, which smelled of ink. He wiped the page with trembling hands and died suddenly.

The theory of celestial bodies clearly points out that all planets revolve around the sun as the center. The book says:

"The earth is moving."

"In addition to the rotation of the earth, there are still some movements that are still wandering. It is actually a planet. "

"among all these planets, the sun is proudly located in the town ... the sun is so high on the throne, ruling the planets around the children."

Although the celestial body movement theory also has some shortcomings, it depicts the real picture of the solar system structure for the first time in human history, reveals the essence of the earth's rotation around the sun, reverses the relationship between the sun and the earth that has been reversed for more than 1000 years, causes a complete revolution in the medieval world outlook, and deals a heavy blow to the theocratic rule of the feudal church.

geocentric theory

Geocentric theory holds that the earth is at the center of the universe, motionless, and the sun, moon, planets and other satellites all revolve around the earth.

The origin of geocentric theory is very early, which was originally put forward by the ancient Greek philosopher Aristotle. Around AD 140, the astronomer Ptolemy further developed his predecessors' theories and established the geocentric theory of the universe. The main points of Ptolemy's geocentric theory are as follows: First, the earth is at the center of the universe and stands still. Second, every planet rotates at a constant speed in a small circular orbit called the current wheel. However, the center of this circle revolves around the earth at a constant speed on a huge circular orbit called "even wheel", but the earth is not in the center of the even wheel, and it has a certain distance from the center. Third, the centers of Mercury and Venus are located on the connecting line between the Earth and the Sun. The centers of Mercury and Venus turn once a year on even-numbered wheels, and the straight lines from Mars, Jupiter and Saturn to their respective centers are absolutely one week. Fourth, all the stars are located on a solid shell called "star sky". In addition to the above movements, the sun, moon and planets, together with the "starry sky", circle the earth once a day.

"Geocentric theory" was always dominant in 100016th century before the foundation of Heliocentrism.