Molchanova M. (9th grade "B")
Comparison of geocentric and heliocentric systems
Modern science has long established that all objects in the Universe are in motion relative to each other. However, earlier, when astronomers did not have the technology at their disposal to establish this for sure, there were different, sometimes contradictory opinions regarding the motion of celestial bodies. Until the Renaissance, the so-called. geocentric(Geo in Greek means "Earth") a picture of the world, according to which the central position in the Universe is occupied by the stationary Earth, around which the Sun, Moon, planets and stars revolve.
Since ancient times, the Earth has been considered the center of the universe. In this case, the presence of the central axis of the Universe and the asymmetry "up-down" were assumed. The earth was kept from falling by a certain support, which in early civilizations was thought of as some kind of giant mythical animal or animals (turtles, elephants, whales). The "father of philosophy" Thales of Miletsky saw a natural object - the world's ocean - as this support. Anaximander of Miletus suggested that the Universe is centrally symmetric and there is no preferred direction in it. Therefore, the Earth located in the center of the Cosmos has no basis to move in any direction, that is, it freely rests in the center of the Universe without support. Anaximander's disciple Anaximenes did not follow the teacher, believing that the Earth was kept from falling by compressed air. Anaxagoras was of the same opinion. Anaximander considered the Earth to be in the form of a low cylinder with a height three times less than the diameter of the base. Anaximenes, Anaxagoras, Leucippus considered the Earth flat, like a table top. A fundamentally new step was taken by Pythagoras, who suggested that the Earth has the shape of a ball. In this he was followed not only by the Pythagoreans, but also by Parmenides, Plato and Aristotle. This is how the canonical form of the geocentric system arose, which was subsequently actively developed by ancient Greek astronomers: the spherical Earth is located in the center of the spherical Universe; the apparent daily movement of the celestial bodies is a reflection of the rotation of the Cosmos around the world axis. As for the order of the luminaries, Anaximander considered the stars to be closest to the Earth, followed by the Moon and the Sun. Anaximenes was the first to suggest that the stars are the most distant objects from the Earth, fixed on the outer shell of the Cosmos. Aristotle believed that there is nothing above the sphere of fixed stars, not even space, while the Stoics argued that our world is immersed in an endless empty space; the atomists, following Democritus, believed that behind our world (limited by the sphere of fixed stars) there are other worlds.
The main "creator" of geocentrism is considered the ancient Roman astronomer Claudius Ptolemy(c. 87-165). In his main work "The Great Construction", also known under the Arabicized name "Almagest", he presented a collection of astronomical knowledge of ancient Greece and Babylon.
During the scientific revolution of the 17th-18th centuries. it turned out that geocentrism is incompatible with astronomical facts and contradicts physical theory; the heliocentric system of the world was gradually established. The main events that led to the rejection of the geocentric system were the creation of the heliocentric theory of planetary motions by Copernicus, the telescopic discoveries of Galileo, the discovery of Kepler's laws and, most importantly, the creation of classical mechanics and the discovery of the law of universal gravitation by Newton. This was an important step on the path of humanity's comprehension of the true picture of the universe.
Heliocentric system of the world - the idea that the Sun is the central celestial body around which the Earth and other planets revolve. Its idea originated in antiquity, but became widespread only from the end of the Renaissance. In this system, the Earth is assumed to revolve around the Sun in one sidereal year and around its axis in one sidereal day. The consequence of the second movement is the apparent rotation of the celestial sphere, the first is the movement of the Sun among the stars along the ecliptic (a large circle of the celestial sphere along which the apparent annual movement of the Sun occurs). In this case, the Sun is considered stationary relative to the stars.
The idea of the Earth's movement arose in antiquity among the representatives of the Pythagorean school. In the Middle Ages, the heliocentric system of the world was practically forgotten. At this time, the tendency of literal reading of the biblical texts prevailed, according to which, among other celestial bodies, it is the Earth that is the main creation of God and therefore is in the center of the universe, and all others revolve around it. This worldview was supported by a visible picture: directly from the surface of the planet, its movement is imperceptible, while the Sun, Moon, stars, like clouds, "move" across the sky.
At the beginning of the Renaissance, the mobility of the Earth was asserted by Nikolai Kuzansky, but his reasoning was purely philosophical, not related to the explanation of specific astronomical phenomena. Leonardo da Vinci was also quite unclear on this topic. In 1450, a Latin translation of Archimedes' Psammit appeared, which mentions the heliocentric system of Aristarchus of Samos. The work was well known to the leading European Renaissance astronomer Regiomontanus. In private correspondence, he noted that "the motion of the stars must undergo tiny changes due to the motion of the Earth." However, Regiomontanus remained a geocentric in his published writings. The movement of the Earth was also mentioned at the turn of the 15th and 16th centuries. In 1499, this hypothesis was discussed by the Italian professor Francesco Capuano, and this meant not only the rotational, but also the translational motion of the Earth (without specifying the center of motion). In 1501, the Italian humanist Giorgio Valla mentioned the Pythagorean doctrine of the Earth's motion around the Central Fire and argued that Mercury and Venus revolve around the Sun.
Heliocentrism was finally revived only in the 16th century, when the Polish astronomer Nicolaus Copernicus (1473-1543) developed a theory of planetary motion around the Sun on the basis of the Pythagorean principle of uniform circular motions. He published the results of his labors in the book "On the Rotations of the Celestial Spheres", published in 1543. Copernicus believed that the Earth makes a threefold movement: 1. Rotation around an axis with a period of one day, which results in the daily rotation of the celestial sphere; 2. Movement around the Sun with a period of a year, leading to the backward motion of the planets; 3. The so-called declination movement with a period of approximately one year, leading to the fact that the axis of the Earth moves approximately parallel to itself. Subsequently, Coprnicus's ideas were supported and developed by other great scientists Giordano Bruno, Johannes Kepler, Galileo Galilei, Rene Descartes. However, from the side of conservative-minded (primarily church) circles, heliocentrism was under serious pressure. Scientists who supported new trends in astronomy were repressed. In particular, Giordano Bruno died at the stake, and the aged Galileo was tried by the church court and only by feigning renunciation of his beliefs saved his life. Protestant and Orthodox churches were also opponents of heliocentrism.
The clergy of the Russian Orthodox Church criticized the heliocentric system of the world until the beginning of the 20th century. Until 1815, a censorship approved a school manual in which the heliocentric system was called "a false system of the philosophical" and "outrageous opinion." The Ural Bishop Arseny, in a letter dated March 21, 1908, advised teachers, when introducing students to the Copernican system, not to give it "unconditional justice", but to teach it "like a fable." The last work in which the heliocentric system was criticized was the book of the priest Job Nemtsev, published in 1914. He argued that "the circle of the earth is motionless, but the sun moves", and justified his statements with the help of quotations from the Bible.
However, even today illiterate people are subject to ancient delusions. According to a 2011 survey by the All-Russian Public Opinion Research Center (VTsIOM), 32% of Russians agree that the Sun revolves around the Earth.
Meanwhile, one must remember that the heliocentric system of the world is not fully true. After all, the Sun is not the center of the universe. It is just one of the many billions of stars in our galaxy, visible from the earth, as it were in profile (the so-called "Milky Way"), and also moves in its huge orbit. Our galaxy is one of the many galaxies in the Universe, the definition of the boundaries of which is not included in the task of this message.
In the preparation of this message were used: A. I. Eremeeva, F. A. Tsitsin History of Astronomy. M .: Publishing house of Moscow State University, 1989; as well as internet data.
The geocentric system of the world is such a concept of the structure of the universe, according to which our Earth is the central body in the entire Universe, and the Sun, Moon, as well as all other stars and planets revolve around it.
Since ancient times, the Earth has been considered the center of the universe, which has a central axis and asymmetry "top - bottom". According to these ideas, the Earth is held in space by means of a special support, which in early civilizations was represented by giant elephants, whales or turtles.
The geocentric system as a separate concept appeared thanks to the ancient Greek mathematician and Miletus. He represented the world ocean as a support for the Earth and assumed that the Universe has a centrally symmetric structure and does not have any designated direction. For this reason, the Earth, located in the center of the Cosmos, is in a state of rest without any support. The student of Anaximander of Miletus, Anaximenes of Miletus, somewhat moved away from conclusions, suggesting that the Earth is held in the space of the Cosmos due to
For many centuries, the geocentric system was the only correct idea of the structure of the world. The point of view of Anaximenes of Miletus was shared by Anaxogoros, Ptolemy and Parmenides. What point of view Democritus adhered to is unknown to history. Anaximander assured that it corresponds to a cylinder, whose height is three times less than the diameter of its base. Anaxogoros, Anaximenes, and Leucillus argued that the earth was flat. The first to suggest that the Earth has the shape of a ball was the ancient Greek mathematician, mystic and philosopher - Pythagoras. Further, the Pythagoreans, Parmenides and Aristotle joined his point of view. Thus, the geocentric system was framed in a different context, its canonical form appeared.
Later, the canonical form of geocentric representations was actively developed by astronomers of ancient Greece. They believed that the Earth has the shape of a ball and occupies a central position in the Universe, which also has the shape of a sphere, and that the Cosmos rotates around the world axis, causing the movement of celestial bodies. The geocentric system is constantly being improved with new discoveries.
So Anaximenes had the assumption that the higher the position of the star, the longer the period of its revolution around the Earth. The order of the luminaries was arranged as follows: the Moon came first from the Earth, followed by the Sun, followed by Mars, Jupiter and Saturn. There were disagreements regarding Venus and Mercury, based on the contradiction in their location. Aristotle and Plato placed Venus and Mercury behind the Sun, and Ptolemy argued that they are between the Moon and the Sun.
The geocentric coordinate system is used in the modern world to study the motion of the Moon and spacecraft around the Earth, as well as to determine the geocentric positions of those moving around the Sun. An alternative to the geocentric theory is according to which the Sun is the central celestial body, and the Earth and other planets revolve around it.
The geocentric system of the world was developed thousands of years ago by Greek philosophers and has been adopted for centuries. Geocentric actually means center. This model is also called the Ptolemaic system of the world after the Greek scientist and philosopher Claudius Ptolemy, despite the fact that the theory existed years before him. The geocentric system of the world places the Earth with, and, circling around it.
Which means that the Sun is in the center, gradually replaced. This new system places the Sun at the center of the Solar System, with the Earth and all other planets orbiting around it. This theory revolutionized everything because it completely changed centuries of established opinion. Although the idea of a heliocentric system of the world appeared as early as 200 BC, it did not gain popularity until the 16th century.
The only reason why the geocentric system of the world has remained popular for so many years is because it explained many of the observations made by the ancient Greeks. For example, the geocentric system of the world explained why objects fall in the direction of the Earth - and also why they appear to remain at the same distance from the Earth, based on its constant brightness. Because astronomers saw problems with the geocentric theory, they modified it in order to explain these discrepancies. Another reason why this model has remained popular for so long is because it developed along with the politics of the Roman Catholic Church.
As we improved, more of the problems facing the geocentric system of the world surfaced. In the 16th century, the astronomer Nicolaus Copernicus, based on the work of ancient scientists, published his heliocentric theory in the book "On the Rotation of the Celestial Spheres." In his book, he made some radical changes, such as the statement that stars do not orbit the Earth and the announcement that this is what makes it look as if the stars were in orbit around the Earth.
The irony is that after all the controversy over these various theories, none were necessarily correct. Einstein's theory of relativity overturns both models. The new evidence has also shown that the solar system's center of gravity is not exactly at the center of the sun. This means that any model is acceptable, regardless of the fundamental differences between the theories. Astronomers use both heliocentric and geocentric models to investigate which theory makes their calculations easier. It certainly seems that some things are relative after all.
Theme . Evolution of ideas about the system of the world: from the geocentric systems of the world of ancient Greek philosophers to the heliocentric system of Copernicus.
Lesson objectives . Using the example of creating a system of the world, show the students:
1) the way of scientific knowledge: facts - hypothesis - facts - new hypothesis -… - theory;
2) the relativity of truth;
3) the ability to interpret the same phenomena in different frames of reference;
Basic concepts . The geocentric system of the world, the heliocentric system of the world.
Demo material . Illustrations. Models.
Students' independent activity. Performing search tasks, creating presentations, organizing material in the form of a table.
Worldview aspect of the lesson. Develop students' logical thinking skills and a scientific approach to the study of the world. The analysis of the accumulation of knowledge in astronomy has been going on since the times of ancient civilizations. Models of the Universe.
Time, min
Techniques and methods
1. Preparation of a report, presentation
Illustrations, models
Performing search tasks
2. Introductory remarks by the teacher
Conversation with students
3. Students' presentation
Illustrations, models
Student speeches
4. Comparison of geocentric and heliocentric theories. Reflection
5. Assignment to the house
Preparation for the lesson.
Students' choice of the topic of the report. Preparation of oral communication, presentation to illustrate the report and newspaper in A5 format.
Literature
Eric Rogers "Physics for the curious", vol. 2, M .: "Mir", 1970., "Planet Earth. Development of ideas and perceptions ”study guide. M .: Interpax, 1994.
Message topics
Universe according to Thales' ideas. The system of the world of Pythagoras. Philolaus' world system. The system of the world Eudoxia. Aristotle's system of the world. The world system of Aristarchus. The Hipparchus World System. Ptolemy's world system. Copernicus' system of the world.
Lesson summary.
The accumulation of knowledge in astronomy has been going on since the times of ancient civilizations, from simple registration of certain facts to systematic observations. From these facts, legends arose that taught children or calmed the common people. In these legends, the Sun was considered a deity, the planet Venus was worshiped, it was told about the "abode of bliss", located above the crystal vault of stars. But the legends themselves weren't just superstitious myths. These were the harbingers of scientific theory, their connection with the facts was weak, rather fantastic, but they created the basis for the "explanation" of these facts. When the Greek civilization was born, its thinkers founded new methods in science: they began to look for general explanatory schemes that appeal to human curiosity. They were no longer content with simple myths to satisfy the curiosity of the crowd. They set themselves the task of "anticipating the phenomenon", that is, to create a scheme that could explain the facts. This was much more important than simply collecting facts or creating a description of each new fact in a separate theory. It was intellectual progress, the beginning of the creation of a scientific theory.
The first Greek scientists drew a simple picture of the structure of the Universe, but as the data accumulated, they complicated the diagrams in order to explain the details of certain phenomena: first, simple facts about the Earth, then more detailed diagrams explaining the movement of the firmament as a whole, as well as the Sun, Moon and planets separately.
At each stage, scientists have tried, based on a few simple assumptions or general principles, to create the most logical and complete "explanation" or description of the observed phenomenon. Such an explanation was supposed to facilitate the systematization of accumulated facts and obtain further predictions. But, first of all, it was supposed to strengthen the belief in the existence of a system that unites various phenomena, in the rational structure of nature. Although the search for a diagram was sometimes dictated by practical necessity, such as the need to create a calendar, the satisfaction that scientists get from clearly explaining a variety of phenomena went far beyond this framework. Forced by the need to ask a question why, Greek philosophers sought and created scientific theories. While our modern quest to test everything by experiment and the wealth of scientific equipment have led to tremendous changes in our thinking, we still share the Greek enthusiasm for a theory that "anticipates phenomena." Let's see how their theories were created.
Assignment to students. While listening to your classmates' presentations, fill in the following fields in the table:
2) facts that did not fit into the previous model of the structure of the universe and explained (or tried to explain) this system of the world;
3) a diagram and a short description of the model of the world.
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600 BC NS. | Diurnal movement of stars, annual and diurnal movement of the Sun and Moon | The Earth is a flat disk, the stars are attached to a rotating sphere, the plane of the ecliptic is inclined relative to the trajectory of the stars (Fig. 1 and Fig. 2)
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530 BC NS. | Moving planets, the sun and the moon against the background of stars at different speeds. | The Earth - the ball is surrounded by concentric transparent spheres, each of which contains celestial bodies: the closest to the Earth - the Moon, then Mercury, Venus, the Sun, Mars, Jupiter, Saturn. The outer sphere contained stars and made a full revolution in a day, the rest rotated more slowly. The general principle is that "spheres" are "perfect" forms, and uniform rotations are "perfect" movements. (fig. 3, 4)
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The Sun, Moon, Venus, Mercury, Venus, Mars, Jupiter, Saturn slowly move among the stars from west to east. The stars move from east to west. | The center of the Universe is not the Earth, but the central fire - the "watchtower of the gods"; The Earth revolves around this fire, making a full revolution in a small orbit per day, and its inhabited part is always facing in the opposite direction from this central fire. This movement of the Earth explained the daily movement of the stars in the sky: the outer crystal sphere could rest at the same time. (Fig. 5)
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Evdoksy 370 BC NS. | The planet does not move unevenly along a loop-like trajectory. The sun and moon move along their annual and monthly trajectories with variable speeds. | The system consists of 27 concentric spheres, like the husks of an onion. Each planet corresponded to several spheres, located one inside the other and revolving around different axes: three spheres for the Sun and the Moon, four for each planet and one outer sphere for all the stars. Each sphere is fixed on an axis that passes through a hole in the next sphere, and is located outside, with the axes of rotation having different directions. Combined movements with properly selected directions of rotation are consistent with observations. (Fig. 6, 7)
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Aristotle 340 BC NS. | The system of the world of Eudoxia did not agree with more accurate observations of the motion of the planets | Increase the number of orbs to 55. He systematized knowledge and gave evidence of the sphericity of the Earth. |
Aristarch 240 BC NS. | The complexity of Aristotle's system led to an attempt to simplify the circuit | 1) The Earth rotates, and this rotation explains the diurnal movement of the stars; 2) The Earth moves around the Sun, making a complete revolution in its orbit during the year; other planets move in the same way - this explains the apparent motions of the Sun and planets relative to the stars. |
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140 BC NS. | Uneven movement of the Sun and Moon, loop-like movement of planets | The planet moves uniformly along a circle (epicycle), the center of which moves uniformly along another circle (deferent), the center of which is already the Earth (Fig. 8, 9)
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Ptolemy 120 BC NS. | Determined the exact positions of the planets, the Sun and the Moon in relation to the fixed stars | The starry sky is a sphere rotating around a fixed axis and making a full revolution in 24 hours. The sun moves around the earth according to the epicyclic scheme of Hipparchus; The moon moves along a more complex epicycloid. To explain the motion of the planets, Ptolemy created a scheme of epicycles in which the Earth is not in the center of the main circle, but would be somewhat shifted relative to it, i.e., it is located eccentrically. But this was not enough, and Ptolemy built a scheme in which he not only positioned the Earth eccentrically, but also shifted the center of uniform rotation in the opposite direction. (Fig. 10)
It was a complex system of main and auxiliary circles with different radii, speeds, inclinations and eccentricities of various sizes and directions. This system, working like a complex transmission mechanism, made it possible from year to year to accurately predict the positions of the planets and determine these positions in the past. Like a good system of mechanisms, it was based on simple principles: circles with constant radii, rotating at a constant speed. |
Copernicus | The motions of all planets in one way or another were consistent with the movement of the Sun, for example, the periods of rotation of Venus and Mercury in terms of the deferents and the periods of rotation of Mars, Jupiter and Saturn in their epicycles were exactly equal to one year - the period of rotation of the Sun around the Earth. | All planets move in orbits around the stationary Sun, the Earth goes around the Sun in a year, while rotating around the axis and completing a full revolution in 24 hours. "Fixed stars" and the Sun rest in the sky. The complex movement of the planet along the epicycloid consists of the planet's own movement in a circle and the movement of the Earth around the Sun. To eliminate the discrepancies between the calculated and observed motions of the planets in the sky, Copernicus was forced to introduce epicycles. |
The motions of the planets observed in the earth's sky could be equally well described within the framework of each of the models of the Universe: both Ptolemy and Copernicus. Let us consider this in more detail using the example of the motion of the inner planets.
1 In the heliocentric model (Fig. 11), corresponding to the real picture, Venus orbits the Sun in 225 days, and the Earth in a year. Since Venus moves around the Sun faster than the Earth, the relative position of these three bodies changes all the time. There are several characteristic configurations: connection (lower and upper), when all three bodies are on the same line, and elongation (western and eastern), when the angle from the Earth to the Sun and Venus is maximum, and reaches 48 °. Identical configurations (for example, lower conjunction) are repeated for Venus every 584 days.
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Rice. 11. Heliocentric model: the period of Venus's revolution around the Sun - 225 days; Earth around the Sun - 1 year.
Rice. 12 Geocentric system of the world of Ptolemy: the period of rotation of Venus according to the deferent - 1 year; on the epicycle - 584 days; the period of the Sun's revolution around the Earth - 1 year
b) The motion of Venus in the Ptolemy's model (Fig. 12) will be presented as a result of movement along the epicycle, coinciding with the orbit of Venus around the Sun, and movement along the deferent, coinciding with the orbit of the Sun around the Earth. If we leave the orbit of the Sun unchanged, but proportionally reduce both the deferent and the epicycle of Venus, then we will thus pass to the Ptolemaic model. The terrestrial observer will not notice this substitution, since the direction to Venus and the Sun will be the same as in the heliocentric one.
Thus, both Ptolemy's model and Copernicus's model were completely interchangeable in geometric terms, so attempts to prove the advantages of one of them are obviously doomed to failure. The truth had to be sought in the discrepancies between the models and the real picture of the motion of the planets, the reason for which was in fact that the planets have not circular, but elliptical orbits. Johannes Kepler managed to understand this.
Initially, Kepler focused almost all of his efforts on studying the motion of Mars. He began his research as a convinced Copernican, but in order to reconcile the available high-precision astronomical data with this model, more and more epicycles had to be introduced into it. Copernicus' model eventually became almost as cumbersome as Ptolemy's, and the calculated motion of Mars across the sky still did not quite match the observed one.
After many years of hard work, Johannes Kepler found a solution to this problem - he rejected the idea of the movement of celestial bodies in circles and postulated that Mars and other planets (including the Earth) revolve around the Sun in elliptical orbits. It was a real scientific revolution: with one blow not only the idea of perfect circular orbits was rejected, but also the model of the Universe with a stationary Earth in the center! Kepler succeeded in surprisingly accurately describing the motions of the planets in the sky and formulating three laws of the motion of celestial bodies, which earned him the name of the "lawgiver of the sky" decades later. The modern heliocentric system is usually called the Copernican system, although it would be more correct to call it the Kepler system.
Kepler's conclusions were so fundamentally at odds with the traditional worldview that for some time they were simply ignored. But around the same years, another event takes place in the Italian city of Pisa, the famous physicist and mechanic Galileo Galilei (1564-1642) used the recently invented "telescope" to study the starry sky. Of course, he was not the first to look at the stars through a telescopic tube, but he was the first who was able to see the phases of Venus, the nature of the change of which could not be explained within the framework of the ancient geocentric model.
In the geocentric model of Claudius Ptolemy, Venus is always located between the Earth and the Sun, and therefore faces the Earth with its shaded side. In this model, only the narrow crescent of Venus should be observed from Earth. In Ptolemy's model, Venus in any of its positions could not be observed in the form of a crescent and more complete phases.
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The "Rotation of Venus" model
Questions to students
1. All statements except one characterize the geocentric system of the world. Please specify an exception.
A) The Earth is located in the center of the world or near it.
B) The planets move around the Earth.
C) The daily movement of the Sun occurs around the Earth.
D) The moon moves around the sun.
E) The daily movement of stars occurs around the Earth.
2. According to ancient astronomers, planets differ from stars in that
A) move in circular orbits;
B) are unlike the Earth in their composition;
C) sometimes move in the direction opposite to the motion of the stars;
D) move around the sun;
D) are closer to the Earth than the Sun.
3. Which of the observed phenomena can be explained within the framework of the geocentric theory? 1) Daily sunrise in the east and sunset in the west.
2) Rotation of the starry sky around the pole of the world.
3) Occasional solar eclipses.
A) 1 and 2.
B) 2 and 3.
B) 1 and 3.
D) everything.
D) none.
4. The heliocentric system of the world explains the loop-like motion of the planets:
A) the difference in the speeds of movement of the Earth and the planet in orbits;
B) the daily rotation of the Earth;
C) a combination of the movement of the Sun along the ecliptic and the movement of planets around the Sun;
D) a change in the speed of the planet's orbit;
E) mutual attraction of the planets.
5. Without which of the following statements is the heliocentric theory inconceivable?
A) The planets revolve around the Sun.
B) The sun is spherical.
C) The earth is spherical.
D) The planets revolve around the Earth.
E) The earth rotates on its axis.
6. Indicate which of the following facts refutes the hypothesis of the immobility of the Earth and the movement of the Sun around it:
A) the daily climax of the Sun.
B) the movement of stars observed during the night.
C) the movement of the Sun against the background of stars, occurring throughout the year.
D) daily sunrise and sunset.
E) none of these facts.
Answers on questions
Tasks 1-6 are taken from the book "Didactic material on astronomy". M., Enlightenment, 1979
Ancient astronomyIt is difficult to say exactly when astronomy was born: almost no information relating to prehistoric times has reached us. In that distant era, when people were completely powerless in front of nature, a belief arose in powerful forces that supposedly created the world and govern it, for many centuries the Moon, the Sun, and the planets were 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 the Earth itself is a heavenly 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 for the immobile center of the universe.
Geocentric system of the world
Hipparchus, an Alexandrian scientist who lived in the 2nd century BC, and other astronomers of his time devoted much attention to observing the motion of the planets.
These movements seemed extremely confusing to them. Indeed, the directions of motion of the planets across the sky seem to describe loops across the sky. This apparent complexity in planetary movement is caused by the movement of the Earth around the Sun - after all, we observe the planets from the Earth, which itself moves. 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 did indeed make such complex movements around the Earth.
In the 2nd century A.D. the Alexandrian astronomer Ptolemy put forward his "system of the world." He tried to explain the structure of the universe, taking into account the apparent complexity of the motion of the planets.
Considering the Earth spherical, and its dimensions are negligible in comparison with the distance to the planets and even more so to the stars. Ptolemy, however, following Aristotle, argued that the Earth is the stationary center of the Universe. Since Ptolemy considered the Earth the center of the universe, his world system was called geocentric.
Geocentric system model.
Around the earth according to Ptolemy, the Moon, Mercury, Venus, the Sun, Mars, Jupiter, Saturn, stars move (in order of distance from the Earth). But if the movement of the Moon, Sun, 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 point. This point, in turn, moves in a circle, in the center of which is the Earth. The circle described by the planet around the moving point was called by Ptolemy an epicycle, and the circle along which the point moves near the Earth was called the deferent.
It is difficult to imagine such intricate movements occurring in nature, and even around imaginary points. Such an artificial construction was required by Ptolemy in order to explain the apparent complexity of the motion of the planets, based on a false idea of the immobility of the Earth, located in the center of the Universe.
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.
The system of the world of Aristotle-Ptolemy seemed plausible to his contemporaries. It made it possible to calculate in advance the motion of the planets for the future time - this was necessary for orientation on the way during travel and for the calendar. This false system has been recognized for almost fifteen hundred years.
Also, this system was recognized by the Christian religion. Christianity based its understanding of the world on the biblical legend of the creation of the world by God in six days. According to this legend, the Earth is the “focus” of the Universe, and the heavenly bodies were created in order to illuminate the Earth and decorate the firmament. Any deviation from these views was mercilessly persecuted by Christianity. The system of the world of Aristotle - Ptolemy, which placed the Earth at the center of the universe, was the best possible answer to the 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 predicted ones. For centuries, it was thought that Ptolemy's system of the world was simply not perfect enough and, trying to improve it, they introduced new and new combinations of circular movements for each planet.
The heliocentric system of the world
His system of the world, the great Polish astronomer Nicolaus Copernicus(1473-1543) stated in the book "On the Rotations of the Celestial Spheres", published in the year of his death. In this book, he proved that the universe is not arranged at all in the way that religion has claimed for many centuries.
In all countries, for almost a millennium and a half, the minds of people were dominated by the false doctrine of Ptolemy, who argued that the Earth rests motionless in the center of the Universe. Followers of Ptolemy, for the sake of the church, invented all new "explanations" and "proofs" of the motion of the planets around the Earth in order to preserve the "truth" and "holiness" of his false teaching. But from this, Ptolemy's system became more and more far-fetched and artificial.
Long before Ptolemy, the Greek scientist Aristarchus argued that the earth moves around the sun. Later, in the Middle Ages, advanced scientists shared the point of view of Aristarchus about the structure of the world and rejected the false teachings of Ptolemy. Shortly before Copernicus, the great Italian scientists Nikolai of Cusansky and Leonardo da Vinci argued that the Earth moves, that it is not at all in the center of the Universe and does not occupy an exceptional position in it.
Why, in spite of this, did the Ptolemy system continue to dominate?
Because it relied on the all-powerful ecclesiastical authority, which suppressed free thought and hindered the development of science. In addition, scientists who rejected the teachings of Ptolemy and expressed correct views on the structure of the Universe could not yet convincingly substantiate them.
Only Nicolaus Copernicus managed to do this. After thirty years of hard work, long reflections and complex mathematical calculations, he showed that the Earth is only one of the planets, and all the planets revolve around the Sun.
Copernicus did not live to see the time when his book spread throughout the world, revealing to people the truth about the universe. He was dying when friends brought and placed the first copy of the book in his chilling hands.
Copernicus was born in 1473 in the Polish city of Torun. He lived in a difficult time, when Poland and its neighbor - the Russian state - continued their centuries-old struggle against the invaders - the Teutonic knights and Tatar-Mongols, who sought to enslave the Slavic peoples.
Copernicus lost his parents early. He was raised by his maternal uncle Lukasz Watzelrode, an outstanding social and political figure of that time. The thirst for knowledge possessed Copernicus from childhood, at first he studied in his homeland. Then he continued his education at Italian universities. Of course, astronomy was studied there according to Ptolemy, but Copernicus carefully studied all the surviving works of great mathematicians and ancient astronomy. Even then, he had thoughts about the correctness of Aristarchus's guesses, about the falsity of Ptolemy's system. But Copernicus was not alone in astronomy. He studied philosophy, law, medicine and returned to his homeland as a comprehensively educated person for his time.
Upon his return from Italy, Copernicus settled in Warmia - first in the city of Litzbark, then in Frombork. His activities were unusually diverse. He took an active part in the management of the region: he was in charge of its financial, economic and other affairs. At the same time, Copernicus tirelessly pondered the true structure of the solar system and gradually came to his great discovery.
What does Copernicus's book "On the Rotation of the Celestial Spheres" contain and why did it deal such a crushing blow to the Ptolemy system, which with all its flaws kept for fourteen centuries under the auspices of the all-powerful ecclesiastical authority in that era? In this book, Nicolaus Copernicus argued that the Earth and other planets are satellites of the sun. He showed that it is the movement of the Earth around the sun and its daily rotation around its axis that explains the apparent movement of the Sun, the strange entanglement in the movement of the planets and the apparent rotation of the firmament.
Simply brilliantly, Copernicus explained that we perceive the movement of distant celestial bodies in the same way as the movement of various objects on Earth when we ourselves are in motion.
We slide in a boat along a calmly flowing river, and it seems to us that the boat and we are motionless in it, and the banks “float” in the opposite direction. In the same way, it only seems to us that the Sun is moving around the Earth. But in fact, the Earth, with everything on it, moves around the Sun and makes a full revolution in its orbit during the year.
And in the same way, when the Earth in its movement around the Sun overtakes another planet, it seems to us that the planet is moving backward, describing a loop in the sky. In reality, the planets move around the Sun in regular, although not perfectly circular orbits, without making any loops. Copernicus, like the ancient Greek scientists, that the orbits along which the planets move can only be circular.
Three quarters of a century later, the German astronomer Johannes Kepler, the successor of the Copernican cause, proved that the orbits of all planets are elongated circles - ellipses.
Copernicus considered the stars to be motionless. Ptolemy's supporters insisted on the immobility of the Earth, argued that if the Earth moved in space, then when observing the sky at different times it should seem to us that the stars are shifting, changing their position in the sky. But such displacements of stars have not been noticed by any astronomer for many centuries. It is in this that the supporters of Ptolemy's teachings wanted to see proof of the immobility of the Earth.
However, Copernicus argued that the stars are at unimaginably great distances. Therefore, their insignificant displacements could not be noticed. Indeed, the distances from us even to the nearest stars turned out to be so great that even three centuries after Copernicus they were amenable to precise definition. It was only in 1837 that the Russian astronomer Vasily Yakovlevich Struve initiated the precise determination of the distances to stars.
It is clear what a tremendous impression the book should have made, in which Copernicus explained the world without regard for religion and even rejecting any authority of the church in matters of science. Church figures did not immediately understand what a blow to religion was dealt by the scientific work of Copernicus, in which he brought the Earth down to the position of one of the planets. For some time, the book was freely distributed among scientists. Not many years have passed, and the revolutionary significance of the great book has fully manifested itself. Other prominent scientists have come to the fore - the successors of the Copernican cause. They developed and spread the idea of the infinity of the Universe, in which the Earth is like a grain of sand, and there are countless worlds. From that time on, the church began a fierce persecution of the supporters of the Copernican teachings.
The new doctrine of the solar system - heliocentric, was affirmed in the fiercest struggle against religion. Copernicus' doctrine undermined the very foundations of the religious worldview and opened a broad path to a materialistic, truly scientific knowledge of natural phenomena.
In the second half of the 16th century, the teachings of Copernicus found their supporters among the leading scientists of different countries. Scientists who have not only promoted Copernicus' doctrine have come to the fore, but have deepened and expanded it.
Copernicus believed that the Universe is limited by the sphere of fixed stars, which are located at unimaginably huge, but still finite distances from us and from the Sun. Copernicus' teachings affirmed the vastness of the Universe and its infinity. Copernicus also for the first time in astronomy not only gave the correct diagram of the structure of the solar system, but also determined the relative distances of the planets from the sun and calculated the period of their revolution around it.
The emergence of a heliocentric worldview
Copernicus' teachings were not immediately recognized. We know that by the verdict of the Inquisition in 1600, an outstanding Italian philosopher, a follower of Copernicus, was burned to death in Rome. Giordano Bruno(1548-1600). Bruno, developing the teachings of Copernicus, argued that there is no and cannot be a center in the Universe, that the Sun is only the center of the Solar system. He also expressed an ingenious guess that the stars are suns like ours, and planets move around countless stars, many of which have intelligent life. Neither torture nor the fire of the Inquisition broke the will of Giordano Bruno, did not force him to renounce the new teaching.
In 1609 Galileo Galilei(1564-1642) first directed a telescope to the sky and made discoveries that clearly confirm Copernicus's discoveries. On the moon he saw mountains. This means that the surface of the moon is to some extent similar to that of the earth, and there is no fundamental difference between “earthly” and “heavenly”. Galileo discovered four moons of Jupiter. Their movement around Jupiter refuted the misconception that only the Earth can be the center of celestial bodies. Galileo discovered that Venus, like the moon, changes its phases. Consequently, Venus is a spherical body that shines with reflected sunlight. Studying the features of the change in the appearance of Venus, Galileo made the correct conclusion that it does not move around the Earth, but around the Sun. On the Sun, which personified “heavenly purity,” Galileo discovered spots and, observing them, found that the Sun revolves on its axis. This means that axial rotation is inherent in various celestial bodies, for example, the Sun. Finally, he discovered that the Milky Way is a multitude of faint stars, invisible 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 discovery 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 forbidden books, and what it contained was contrary to Scripture. Galileo was forbidden to propagate the teachings of Copernicus. However, in 1632 he nevertheless managed to publish the book "Dialogue on the two main systems of the world - Ptolemaic and Copernican", in which he was able to convincingly show the truth of the heliocentric system, which brought the wrath of the Catholic Church upon himself. In 1633, Galileo appeared before the court of the Inquisition. The aged 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 did the Catholic Church finally acquit Galileo.
The execution of Bruno, the official ban on the teachings of Copernicus, and the trial of Galileo could not stop the spread of Copernicus. 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 of universal gravitation. In Russia, Copernicus' teachings boldly supported M. V. Lomonosov(1711-1765), who discovered the atmosphere on Venus, defended the idea of a plurality of inhabited worlds.
