Already in ancient times, people wanted to get answers to such important questions, like “what is our Earth?”, “what is its size?”, “what is its place in the Universe?” etc. But the search for answers turned out to be long and difficult.
“The first answers to the question “how does it work?” the world? Ancient people made up their calculations on the basis of their direct impressions,” A.I. Klimishin writes in his book, “so, without feeling any movements of the Earth, people naturally assumed that it was motionless. Observing how the Sun, the Moon, and the entire sky revolved around the Earth, they perceived this as an immutable fact. They had no reason to doubt that the Earth was flat. And finally, the assumption that it is located in the center of the world seemed so logical...
In Ancient Babylon, the idea was formed that the Earth had the appearance of a convex round island floating in the world's oceans. The sky seems to rest on the earth's surface - a solid stone vault to which the stars and planets are attached and along which the Sun makes its daily walk. It is noteworthy that among the ancient Sumerians the word “na” meant both “sky” and “stone”. Later, the main elements of this Babylonian model of the world are also found among the ancient Jews; in particular, the authors of the Bible adhered to it. For example, in the book of Job it is said that “God... spread out the heavens, solid as a cast mirror” (Job, 37, 18).” Probably in Ancient Greece for the first time they tried to scientifically explain these phenomena, to unravel the real reason their appearance. Thus, the outstanding thinker Heraclitus of Ephesus (about 544-470 BC) suggested the continuous development of the world. According to Democritus (about 460-370 BC), the Universe consists of an infinite number of worlds formed as a result of the collision of atoms, with some worlds being born, others flourishing, and others being destroyed. Democritus assumed that the Milky Way was a collection of a large number of stars.
Pythagoras came across the idea that the Earth is spherical and that it hangs in space without any support. Aristotle (384-322 BC) in his work “On the Heavens” already gives the size of the earth’s circumference, from which it follows that the radius of the Earth in modern terms is equal to approximately 10,000 kilometers of earth, water, air and fire, while the celestial bodies consist of another, indestructible form of matter - ether. The scientist argued that the four “elements” mentioned are located above each other in the form of concentric spheres. Each element, having moved from its “natural” place, strives to occupy it again. Therefore, they say, in nature, heavy elements move downward (towards the “center of the Universe”), and light ones move upward, where they go into a state of rest. Aristotle and his followers opposed the ideas that already existed at that time about the possible rotation of the Earth around its axis and its movement in space. They put forward evidence that seemed irrefutable at that time: if the Earth rotated around its axis, then a head wind would arise that would blow everything from its surface towards the west, and the Earth’s movement would inevitably be detected by the change throughout the year in the angular distance between arbitrarily taken from the sky by a pair of stars.
Now known: earth's atmosphere equally takes part in the daily rotation of the Earth, but the distances to the stars turned out to be so great that Aristotle had no chance of determining such a change.
The work of Aristarchus of Samos (about 320-230 BC) has survived to this day. He was able to measure the angular distance of the Moon from the Sun in the first quarter. He also made an attempt to determine the sizes and distances to the Moon and the Sun. According to Aristarchus, the distance from the Earth to the Moon is 19 Earth radii, and to the Sun is another 19 times greater. Apparently, having in mind the large size of the Sun compared to the Earth, Aristarchus suggested “that the fixed stars and the Sun do not change their place in space, that the Earth moves in a circle around the Sun,” as Archimedes later reported.
In the 2nd century BC, the greatest ancient astronomer Hipparchus determined the dimensions of the Moon with exceptional accuracy. According to Hipparchus, the radius of the Moon is 0.27 Earth radii, which differs little from what is currently accepted. This outstanding astronomer determined the distance to the Moon to be 59 Earth radii (the true average value is 60.3). However, the distance to the Sun from the time of Ptolemy until the 17th century was taken equal to 1120, i.e. approximately 20 times less than the true one.
The first attempts to build a model of the world that would explain the forward and backward movements of the planets were made by Eudoxus of Cnidus (about 408-353 BC) and Aristotle. But the masterpiece of ancient astronomy was the work of the outstanding Alexandrian scientist Claudius Ptolemy (2nd century AD) “Almagest”, in which a new theory of planetary movements was built.
At that time, all other natural sciences were still in their infancy. Astronomers, thanks to Ptolemy, already had a method that made it possible to calculate the position of the planets in the sky for any number of years in advance with sufficient accuracy for that time!
In Ptolemy’s geocentric model of the world, one planet moves with angular velocity along a small circle - an epicycle, the center of which, i.e., the other “middle planet,” rotates with angular velocity along the deferent around the Earth. Due to the addition of both movements, the planet in space describes a loop-shaped curve - hypocycloid, which in projection onto the celestial sphere at completely certain values angular velocities, as well as the ratio of the epicycle radius to the deferent radius for each of the planets, fully explained its movement in the sky. Ptolemy determined these values with great accuracy.
Due to the peculiarities of their movement, the planets Mercury and Venus were called inferior. Mars, Jupiter and Saturn are the upper planets. In the Ptolemaic world system, the centers of the epicycles of the lower planets are always located on the straight line connecting the Earth with the Sun, and each of the upper planets is located on the epicycle strictly in the same direction in which the Sun is relative to the Earth, in other words, the radius vectors of the epicycles of Mars, Jupiter and Saturn are always parallel to each other. It can also be seen that the upper planet, occupying a position in the sky opposite to the Sun (opposition of the planet), is in the closest position to the Earth - in perigee (from the Greek “peri” - close) At the moment of the planet’s conjunction with the Sun, when the directions are towards both luminaries coincide, the planet is at its apogee - at the point most distant from the Earth (from the Greek “apo” - far).
As noted by A.I. Klimishin, “the question arises: if the Ptolemaic system is erroneous, since it was based on a false idea of the stationary Earth as the center of the universe, then why do the calculations carried out on its basis give the correct results? After all, that is why it has been used by astronomers for almost 1400 years. The answer to the question posed is obvious: this is a kinematic system. Ptolemy did not explain (and could not explain) why the movement of the planet was exactly the way he described it. But every movement is relative. And, paradoxical as it may sound, Ptolemy described and modeled the movement of each of the planets absolutely correctly - the way an observer from Earth actually sees it. The epicycle of the upper planet is a reflection of the movement of the Earth around the Sun (in the case of the lower planet, this is its deferent).”
But “...with the help of Ptolemy’s data, it was difficult to harmonize information about the positions of one or another planet, separated by a period of time of several hundred years. Therefore, his system became more and more complicated, many additional epicycles were introduced into it, which made it extremely cumbersome. Ptolemy's theory of the motion of the Moon clearly contradicted observations. As a result, Ptolemy’s model, overloaded with epicycles, collapsed. There has been a revolution in views on the world and the place of the Earth in the Universe...”
World systems are ideas about the location in space and movement of the Earth, Sun, Moon, planets, stars and other celestial bodies.
Already in ancient times, the first ideas about the place of the Earth in the Universe were formed.
These world systems were extremely naive: a flat Earth, under which there is an underworld, and above it the vault of heaven rises. With the accumulation of observational data on the visible movements of celestial bodies and the development of science, in particular geometry and mechanics, these views changed. A huge step forward in the development of astronomical knowledge was the idea of the starry sky as a complete sphere and the assumption of the sphericity of the Earth. Ancient Greek scientists and philosophers made serious attempts to develop harmonious, mainly geocentric systems of the world with a spherical Earth at the center of the finite Universe, which was, as it were, enclosed by the sphere of fixed stars.
These systems were based on the assumption that the entire Universe was created for the Earth, the whole world and all the heavenly bodies should serve the Earth.
In its clearest form, the geocentric system of the world was developed by the great ancient scientist Aristotle (IV century BC). His ideas were developed and completed by the Alexandrian astronomer Q. Ptolemy (2nd century AD). Ptolemy outlined his system of the world in the book “Almagest”.
According to the Ptolemaic world system, the Earth is located at the center of the Universe, surrounded by more than 50 transparent crystal spheres. They have common center and control the movement of the Moon, Mercury, Venus, Sun, Mars, Jupiter, Saturn and the stars. To control the movement of the Sun and Moon, two spheres (one for each luminary) were allocated with circles located on them - deferents, along which the Sun and Moon moved.
But for planets with their complex movements this was not enough. Therefore, Ptolemy believed that it was not the planet itself that moved along the deferent, but the center of another circle of somewhat smaller dimensions - the so-called epicycle. The center of the next epicycle moves along this epicycle, etc. The planet rotates only along the very last epicycle. The outer sphere of the fixed stars makes a full revolution around its axis during the day and sets the remaining spheres in motion, thereby providing a visible picture of the movement of the heavenly bodies.
With the help of epicycles and deferents, it was possible to quite accurately describe the observed movements of the planets and pre-calculate the positions of celestial bodies for the future.
The geocentric system of the world of Aristotle-Ptolemy was in agreement with the religious doctrine of the central place of the Earth in the Universe, and therefore the church for many centuries prevented the development of correct scientific ideas about the structure of the world. Small changes were made to the Ptolemaic system, but its basic principle remained unchanged.
Geocentric cosmology.
Claudius Ptolemy (dawn of activity 127-148, Alexandria)
Ptolemy’s main work “The Great Mathematical Construction of Astronomy in 13 Books” (Arabic title “Almagest”) is an encyclopedia of the astronomical knowledge of the ancients.
First created mathematical theory, describing the movement of the Sun and Moon, as well as the five then known planets in the visible sky.
At the center of the Universe is the motionless Earth. Closer to Earth is the Moon, followed by Mercury, Venus, Sun, Mars, Jupiter and Saturn - the faster a planet moves, the closer it is to Earth.
Aristotle - ideas about motion.
The movements of celestial and terrestrial bodies are different.
The luminaries perform a uniform circular motion (composed of circular motions), which has neither beginning nor end and does not require external influence.
The movement of earthly bodies has a beginning and an end and is divided into natural (bodies consisting of the elements of earth - downward, and those consisting of elements of air and fire - upward) and violent.
Violent movement occurs only under the influence of an external force. The speed of movement of bodies is proportional to the applied force.
Aristotle - continuum concept.
- Most likely, our planet revolves around the Sun. The reason for this is the size of the Sun, which is significantly larger than the size of the Earth. Information about relative values The Earth, Moon and Sun were derived from Aristarchus's own calculations.
- Due to the absence of visible annual parallaxes of stars, he suggested that the orbit of our planet appears to be a point relative to the distances to the stars.
- As a result of the movement of the Earth, which alternately approaches and then moves away from any of the planets of our system, these planets make the so-called. backward movement. That is, after a certain period of time they begin to move to reverse side from the direction of movement of the Sun.
- Anticipation of the equinoxes. Over the course of 18 centuries, scientists have been looking for the reasons for such an effect as the anticipation of the equinoxes, according to which every year the spring equinox occurs a little earlier. In his writings, Nicolaus Copernicus was able to describe this effect as a consequence of the periodic displacement of the earth's axis.
- In the footsteps of Aristarchus of Samos, Copernicus argued and also proved that the sphere of stars is located at a very long distance relative to the distances between planets, as a result of which scientists do not observe annual parallaxes. And he confirmed the assumption about the rotation of our planet around its axis with the following: if our planet is still motionless, then the rotation of the sky should occur due to the rotation of the stellar sphere itself, and given the calculated distance to it, the speed of its rotation will be unimaginably high.
- The planes of the planetary orbits of the solar system intersect at the location of the sun, which made it the center of their rotation, and not the center of the earth's orbit, as Copernicus assumed.
- The orbital speed of our planet changes periodically, just like other planets.
- The orbits of the planets are elliptical, and the speed of movement of celestial bodies along them directly depended on the distance to the Sun, which made it not only the geometric, but also the dynamic center of the planetary system.
"Nature abhors a vacuum."
The luminaries do not move on their own, but are attached to material spheres.
Any movement is possible only in filled space (for example, the movement of a ball in the air).
The existence of emptiness is impossible, since in emptiness any movement would instantly begin and also end instantly.
The heliocentric system of the world is the idea that the Sun is the center of the universe and the point around which all planets, including the Earth, revolve. This system suggests that our planet performs two types of motion: translational around the Sun and rotational around its axis. The position of the Sun itself relative to other stars is considered unchanged.
The term "heliocentrism" comes from Greek word"helios" (translated as "Sun").
It is possible to find a certain central point of the Universe only if the Universe . It owes this according to the heliocentric system of the world.
Also in this system the concept of external and internal planets arose. The latter included Mercury and Venus, because their orbits around the Sun must always be within the Earth's orbit.
The most important feature of heliocentrism is the annual parallaxes of stars. This effect manifests itself in the form of a change in the apparent coordinates of the star. It is associated with a change in the position of observers (astronomers), which arose due to the rotation of the Earth around the Sun.
Heliocentrism in antiquity and the Middle Ages
The idea that the Earth moves around a certain center of the whole world arose in the minds of the ancient Greeks. So there were assumptions about the rotation of the Earth around its axis, as well as about the movement of Mars and Venus around the Sun, which together with them revolves around our planet. However, it is believed that the heliocentric system of the world was first outlined in the 3rd century BC. e. Aristarchus of Samos. He made two important conclusions:
However, Aristarchus' ideas did not become widespread in antiquity. The most famous version of the geocentric system in Ancient Greece was the so-called theory of homocentric spheres, which was developed by the astronomers Eudoxus, Callippus and Aristotle. According to this theory, all celestial bodies revolving around our planet were fixed on rigid spheres, interconnected and having a single center - the Earth.
In connection with such a worldview of the prevailing part of society, other adherents of the idea of Aristarchus of Samos did not express their views, as a result of which the Greeks abandoned this idea and completely accepted geocentrism. Any schools that taught rationalism at that time did not support the ideas of Aristarchus, since they considered the nature of the universe to be beyond understanding and excluded any possibility of describing the dynamics of the planets.
In the Middle Ages, heliocentrism was hardly mentioned in scientific works, except for some of his ideas, for example, the rotation of the Earth around its axis.
Scientific revolution of Nicolaus Copernicus
In 1543, the Polish astronomer, mechanic and clergyman Nicolaus Copernicus published his scientific work, which was called: “On the rotation of the celestial spheres.” In it, the astronomer described the heliocentric theory, confirming it with a number of physical calculations based on the then theoretical mechanics. According to his concept, the change of day and night, as well as the movement of the Sun across the sky, are explained by the rotation of the Earth around its axis. In the same way, with the help of the Earth around the Sun, the movement of our star across the sky throughout the year is explained.
Copernicus explained the following phenomena:
In addition, the heliocentric system could explain the change in the brightness and size of the planets of the Solar System, as well as provide a more accurate estimate of the sizes of the planets and the distances to them. Nicolaus Copernicus himself was able to approximately determine the sizes of the Moon and the Sun and indicate as accurately as possible the time during which Mercury completely passes its orbit around the Sun - 88 Earth days.
Despite the complete revolution in the field of astronomy, Copernicus' theory had several shortcomings. Firstly, the central point of the system he described remained the center of the Earth's orbit, and not the Sun. Secondly, all the planets of our planetary system moved unevenly in their orbits, but our planet maintained its orbital speed. And also, most likely, Copernicus did not discard the idea of rotating celestial spheres, but only transferred the center of their rotation.
Followers and opponents of Copernicus
Subsequently, the Polish astronomer gained a large number of followers, including Giordano Bruno, who argued that the firmament is not limited to the celestial spheres, and that other luminaries are celestial bodies in no way inferior to the Sun. Unfortunately, Bruno was labeled a heretic for his beliefs and sentenced to be burned.
The famous Italian scientist supported the Copernican theory, relying on his own observations. He also argued that the Earth never occupied a place between Mercury (or Venus) and the Sun, which indicated the rotation of these two planets around the star in orbits located inside the Earth's. The opposite statement proved the location of the Earth's orbit inside the orbits outer planets. Because of his beliefs, the 70-year-old Galileo was subjected to an inquisitorial trial in 1633, which resulted in him being under “house arrest” until his death at 78.
Opponents of heliocentrism insisted on several arguments refuting the Copernican theory. If the Earth rotated around its axis, the monstrous centrifugal force would tear it apart. Moreover, all light objects would fly off its surface, and they would move in the direction opposite to the rotation. It was assumed that all celestial objects have no mass, so they can move without applying large forces to them. In the case of the Earth, the question arose about the existence of a colossal force that could rotate our massive planet.
One of the opponents of geocentrism, the outstanding Danish astronomer Tycho Brahe, developed the so-called “geo-heliocentric” system of the world, according to which the sphere of stars, the Moon and the Sun move around the Earth, and other space objects around the Sun.
After some time, Brahe’s successor, the German physicist Johannes Kepler, having analyzed an impressive volume of observational results from his mentor, made several significant discoveries in favor of heliocentrism:
The so-called Kepler's laws were formulated, which described in detail and in mathematical language the laws of motion of the planets of the solar system.
Affirmation of heliocentrism
As a result of confirmation of the rotation of the Earth around its axis, any need for the existence of celestial spheres disappeared. For some time it was assumed that the reason planets move is because they are living things. However, Kepler soon determined that the motion of the planets arises as a result of the influence of the gravitational forces of the Sun on them.
In 1687, the English physicist Isaac Newton, relying on his own, confirmed the calculations of Johannes Kepler
With the further development of science, scientists received more and more arguments in favor of heliocentrism. Thus, in 1728, an astronomer from England, James Bradley, for the first time, using observation, confirmed the theory of the Earth’s orbit around the Sun, discovering the so-called aberration of light. The latter means a slight blurring of the star's image on one side as a result of the movement of the observer. Later, an annual fluctuation in the frequency of pulses emitted by pulsars, as well as for stars, was discovered, which proves a periodic change in the distance of the Earth to these space objects.
And in 1821 and 1837 Russian-German scientist Friedrich Wilhelm Struve was for the first time able to observe the approximate annual parallaxes of stars, which finally confirmed the idea of a heliocentric system of the world.
Astronomy in ancient times
It is difficult to say exactly when astronomy began: almost no information relating to prehistoric times has reached us. In that distant era, when people were completely powerless over nature, a belief arose in powerful supernatural forces that supposedly created the world and control it. For many centuries, the planets have been deified. We learn about this from the myths of all the peoples of the world.
The first ideas about the universe were very naive, they were closely intertwined with religious beliefs, which were based on the division of the world into two parts - earthly and heavenly. If now every schoolchild knows that she herself is a celestial body, then earlier “earthly” was opposed to “heavenly”. They thought that there was a “firmament of heaven” to which the stars were attached, and the Earth was taken as the fixed center of the universe.
Geocentric systems of the world
The idea of the central position of the Earth in the Universe was subsequently used by scientists of Ancient Greece as the basis for geocentric systems of the world. Thus, the greatest Greek philosopher and scientist - encyclopedist Aristotle (384 - 322 BC), who already knew (from observations lunar eclipses) that the Earth is spherical, believed that the planet is motionless. He noted that if the Earth were moving, then this movement could be detected by the position of the stars in the sky - they would change. In fact, such apparent (or parallactic) displacements of stars do occur, but due to the enormous distance of the stars, these displacements are negligible and were first discovered only in the 19th century.
Achievements of ancient astronomy in the 2nd century. n. e. summarized by the Alexandrian astronomer Claudius Ptolemy. He developed a geocentric system of the world, according to which the Moon, Sun, and the “sphere of fixed stars” move around the motionless Earth. For many centuries, the church supported a geocentric system of the world, in which, as in church teaching itself, the Earth was assigned the position of “the center of the Universe.”
Despite the fact that Ptolemy’s system of the world was based on completely erroneous ideas about the structure of the Universe, it still explained many features of the visible movement of the celestial bodies, and in particular the loop-like movement of the planets. Ptolemy achieved this by considering the movement of each planet as a combination of several uniform movements. For example, it was believed that the planet did not simply move around the Earth, but moved around a point that itself revolved around the Earth. The tables compiled by Ptolemy made it possible to determine in advance the position of the planets in the sky. But over time, astronomers discovered a discrepancy between the observed positions of the planets and the pre-calculated ones. For centuries it was thought that the Ptolemaic system of the world was simply not perfect enough and, in an attempt to improve it, they introduced new and new combinations of circular motions for each planet.
Heliocentric system of the world
The great Polish astronomer Nicolaus Copernicus (1473 - 1543) outlined his system of the world in the book “On the Rotations of the Celestial Spheres,” published in the year of his death. According to his teaching, the center of the world is not Earth, and the Sun. Only the Moon moves around the Earth. The Earth itself is the third planet farthest from the Sun and the most planet closest to Earth- Venus. The Earth revolves around the Sun and rotates on its axis. Beyond the Earth's orbit are the orbits of Mars, Jupiter and Saturn. At a very great distance from the Sun, Copernicus placed the “sphere of fixed stars.”
The world system proposed by Copernicus is called heliocentric. He simply and naturally explained the loop-like motion of the planets by the fact that we observe the planets revolving around the Sun not from the moving Earth, but from the Earth, which is also moving around the Sun. For the first time in astronomy, Copernicus not only gave correct scheme structure of the solar system, but also determined the relative distances (in units of the distance of the Earth from the Sun) of the planets from the Sun and calculated the period of their revolution around it.
The teachings of Copernicus dealt a crushing blow to the geocentric system of the world. It went far beyond the scope of astronomical science, becoming a powerful impetus for the development of all natural sciences.
The formation of a heliocentric worldview
The teachings of Copernicus were not immediately recognized. According to the verdict of the Inquisition in 1600, the outstanding Italian philosopher, follower of Copernicus Giordano Bruno (1548 - 1600) was burned in Rome. Bruno, developing the teachings of Copernicus, argued that there is and cannot be a center in the Universe, that Sun- this is just the center solar system. And the Earth is a planet solar system. He also expressed a brilliant guess that the stars are the same suns as ours, and planets move around countless stars, many of which support intelligent life. Neither torture nor the fire of the Inquisition broke the will of Giordano Bruno or forced him to renounce the new teaching.
In 1609, Galileo Galilei (1564 - 1642) first pointed a telescope at the sky and made discoveries that clearly confirmed the teachings of Copernicus. On the moon he saw mountains. This means that the surface of the Moon is to some extent similar to the earth’s and there is no fundamental difference between “earthly” and “heavenly”. Galileo discovered four moons of Jupiter. Their movement around Jupiter refuted the erroneous idea that only the Earth can be the center of movement of celestial bodies. Galileo discovered that Venus is a spherical body that shines by reflected sunlight. Studying the features of the change in the appearance of Venus, Galileo made the correct conclusion that it moves not around the Earth, but around the Sun. On the Sun, which personified “heavenly purity,” Galileo discovered spots and, observing them, established that the Sun rotates around its axis. So, different celestial bodies, for example, the Sun, is characterized by axial rotation. Finally, he discovered that the Milky Way is made up of many faint stars that are not visible to the naked eye. Consequently, the Universe is much grander than previously thought, and it was extremely naive to assume that it makes a complete revolution around the small Earth in a day.
Galileo's discoveries increased the number of supporters of the heliocentric system of the world and at the same time forced the church to intensify the persecution of the Copernicans. In 1616, Copernicus’s book “On the Rotations of the Celestial Spheres” was included in the list of prohibited books, and the teaching contained in it was declared contradictory Holy Scripture. Galileo was forbidden to propagate the teachings of Copernicus. However, in 1632 he still managed to publish the book “Dialogue about two major systems world – Ptolemaic and Copernican”, in which he was able to convincingly show the truth of the heliocentric system, which brought upon himself the wrath of the Catholic Church. In 1633, Galileo appeared before the Inquisition. The elderly scientist was forced to sign a “renunciation” of his views and was kept under the supervision of the Inquisition for the rest of his life. Only in 1992 Catholic Church finally acquitted Galileo.
The execution of Bruno, the official ban on the teachings of Copernicus, and the trial of Galileo could not stop the spread of Copernicanism. In Austria, Johannes Kepler (1571 - 1630) developed the teachings of Copernicus, discovering the laws of planetary motion. In England, Isaac Newton (1643 - 1727) published his famous law universal gravity. In Russia, the teachings of Copernicus were boldly supported by M.V. Lomonosov (1711 - 1765), who discovered the atmosphere on Venus, defended the idea of a plurality of inhabited worlds and ridiculed supporters of geocentrism in witty poetry.
Gipparchus, Alexandrian scholar who lived in the 2nd century BC. e., and other astronomers of his time paid a lot of attention to observations of the movements of the planets. These movements seemed extremely confusing to them. In fact, the directions of movement of the planets across the sky seem to describe loops across the sky. This apparent complexity in the movement of the planets is caused by the movement of the Earth around the Sun - after all, we observe the planets from the Earth, which itself is moving. And when the Earth “catches up” with another planet, it seems that the planet seems to stop and then moves back. But ancient astronomers thought that the planets actually made such complex movements around the Earth.
In the 2nd century AD. Alexandrian astronomer Ptolemy put forward his "system" peace"He tried to explain the structure of the Universe, taking into account the apparent complexity of the movement of the planets. Considering the Earth to be spherical, and its dimensions insignificant compared to the distance to the planets and especially the stars. Ptolemy, however, following Aristotle, argued that The Earth is the immovable center of the Universe. Since Ptolemy considered the Earth to be the center of the Universe, he system peace was called geocentric. According to Ptolemy, the Moon, Mercury, Venus, Sun, Mars, Jupiter, Saturn, and stars move around the earth (in order of distance from the Earth). But if the movement of the Moon, Sun, and stars is circular, then the movement of the planets is much more complicated. Each of the planets, according to Ptolemy, does not move around the Earth, but around a certain point. This point, in turn, moves in a circle, in the center of which is the Earth. Ptolemy called the circle described by the planet around a moving point an epicycle, and the circle along which a point moves near the Earth was called a deferent.
It is difficult to imagine such intricate movements taking place in nature, especially around imaginary points. Such an artificial construction was required by Ptolemy in order, based on the false idea of the immobility of the Earth, located in the center of the Universe, to explain the apparent complexity of the movement of the planets. Ptolemy was a brilliant mathematician for his time. But he shared the view of Aristotle, who believed that the Earth is motionless and only it can be the center of the Universe. System peace Aristotle-Ptolemy seemed plausible to his contemporaries. It made it possible to calculate in advance the movement of the planets for the future - this was necessary for orientation during travel and for the calendar. This false system has been recognized for almost fifteen hundred years. This system was also recognized by the Christian religion. Christianity based its worldview on biblical legend about creation peace By God in six days. According to this legend, the Earth is the “center” of the Universe, and the heavenly bodies were created in order to illuminate the Earth and decorate the firmament. Christianity mercilessly persecuted any deviation from these views. System peace Aristotle - Ptolemy, who placed the Earth at the center of the universe, perfectly corresponded to Christian doctrine. The tables compiled by Ptolemy made it possible to determine in advance the position of the planets in the sky. But over time, astronomers discovered a discrepancy between the observed positions of the planets and the pre-calculated ones. For centuries it was thought that system peace Ptolemy is simply not perfect enough and, in an attempt to improve it, they introduced new and new combinations of circular movements for each planet.