What is at the center of the Earth? Internal structure of the planet. Gloria - Earth's twin What is happening inside our planet

Development of geocentrism

Since ancient times, the Earth was considered the center of the universe. In this case, the presence of a central axis of the Universe and “top-bottom” asymmetry were assumed. The earth was kept from falling by some kind of support, which in early civilizations was thought to be some kind of giant mythical animal or animals (turtles, elephants, whales). The first ancient Greek philosopher Thales of Miletus saw a natural object - the world ocean - as this support. Anaximander of Miletus suggested that the Universe is centrally symmetric and does not have any distinguished direction. Therefore, the Earth, located in the center of the Cosmos, has no reason to move in any direction, that is, it rests freely in the center of the Universe without support. Anaximander's student Anaximenes did not follow his teacher, believing that the Earth was kept from falling by compressed air. Anaxagoras was of the same opinion. Anaximander's point of view was, however, shared by the Pythagoreans, Parmenides and Ptolemy. The position of Democritus is not clear: according to various evidence, he followed Anaximander or Anaximenes.

Anaximander considered the Earth to be in the shape of a low cylinder with a height three times less than the diameter of the base. Anaximenes, Anaxagoras, Leucippus believed that the Earth was 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, subsequently actively developed by ancient Greek astronomers: the spherical Earth is located in the center of the spherical Universe; The visible 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 located closest to the Earth, followed by the Moon and the Sun. Anaximenes was the first to suggest that stars are the objects farthest from Earth, fixed on the outer shell of the Cosmos. In this, all subsequent scientists followed him (with the exception of Empedocles, who supported Anaximander). An opinion arose (for the first time, probably, among Anaximenes or the Pythagoreans) that the longer the period of revolution of a luminary in the celestial sphere, the higher it is. Thus, the order of the luminaries was as follows: Moon, Sun, Mars, Jupiter, Saturn, stars. Mercury and Venus are not included here because the Greeks had disagreements about them: Aristotle and Plato placed them immediately behind the Sun, Ptolemy - between the Moon and the Sun. Aristotle believed that there was nothing above the sphere of the fixed stars, not even space, while the Stoics believed that our world is immersed in endless empty space; atomists, following Democritus, believed that beyond our world (limited by the sphere of fixed stars) there are other worlds. This opinion was supported by the Epicureans, and was vividly expressed by Lucretius in his poem “On the Nature of Things.”

Stored in the National Library of France.

Justification for geocentrism

Ancient Greek scientists, however, substantiated the central position and immobility of the Earth in different ways. Anaximander, as already indicated, pointed out the spherical symmetry of the Cosmos as the reason. Aristotle did not support him, putting forward a counter-argument, later attributed to Buridan: in this case, a person located in the center of a room in which there is food near the walls should die of hunger (see Buridan's donkey). Aristotle himself justified geocentrism as follows: The Earth is a heavy body, and the natural place for heavy bodies is the center of the Universe; as experience shows, all heavy bodies fall vertically, and since they move towards the center of the world, the Earth is in the center. In addition, Aristotle rejected the orbital motion of the Earth (which was assumed by the Pythagorean Philolaus) on the grounds that it should lead to a parallactic displacement of stars, which is not observed.

A number of authors provide other empirical arguments. Pliny the Elder, in his encyclopedia Natural History, justifies the central position of the Earth by the equality of day and night during the equinoxes and the fact that during the equinox, rising and setting are observed on the same line, and the sunrise on the day of the summer solstice is on the same line , which is the same as sunset on the day of the winter solstice. From an astronomical point of view, all these arguments are, of course, a misunderstanding. Little better are the arguments given by Cleomedes in the textbook “Lectures on Astronomy”, where he substantiates the centrality of the Earth by contradiction. In his opinion, if the Earth were east of the center of the Universe, then the shadows at dawn would be shorter than at sunset, the celestial bodies at sunrise would appear larger than at sunset, and the duration from dawn to noon would be shorter than from noon until sunset. Since all this is not observed, the Earth cannot be shifted to the west from the center of the world. Similarly, it is proved that the Earth cannot be shifted to the west. Further, if the Earth were located north or south of the center, the shadows at sunrise would extend in a north or south direction, respectively. Moreover, at dawn on the days of the equinoxes, the shadows are directed exactly in the direction of sunset on these days, and at sunrise on the day of the summer solstice, the shadows point to the point of sunset on the day of the winter solstice. This also indicates that the Earth is not offset north or south of center. If the Earth were above the center, then less than half of the sky could be observed, including less than six signs of the zodiac; as a consequence, the night would always be longer than the day. It is similarly proven that the Earth cannot be located below the center of the world. Thus, it can only be in the center. Ptolemy gives approximately the same arguments in favor of the centrality of the Earth in the Almagest, Book I. Of course, the arguments of Cleomedes and Ptolemy only prove that the Universe is much larger than the Earth, and therefore are also untenable.

Pages from SACROBOSCO "Tractatus de Sphaera" with the Ptolemaic system - 1550

Ptolemy also tries to justify the immobility of the Earth (Almagest, book I). Firstly, if the Earth were displaced from the center, then the effects just described would be observed, but since they are not, the Earth is always in the center. Another argument is the verticality of the trajectories of falling bodies. Ptolemy justifies the absence of axial rotation of the Earth as follows: if the Earth rotated, then “... all objects that do not rest on the Earth should seem to make the same movement in the opposite direction; neither clouds nor other flying or hovering objects will ever be seen to move eastward, since the earth's eastward motion will always throw them off, so that these objects will appear to move westward, in the opposite direction." The inconsistency of this argument became clear only after the discovery of the foundations of mechanics.

Explanation of astronomical phenomena from the position of geocentrism

The greatest difficulty for ancient Greek astronomy was the uneven movement of the celestial bodies (especially the retrograde movements of the planets), since in the Pythagorean-Platonic tradition (which Aristotle largely followed), they were considered deities who should only make uniform movements. To overcome this difficulty, models were created in which the complex apparent movements of the planets were explained as the result of the addition of several uniform circular movements. The concrete embodiment of this principle was the theory of homocentric spheres of Eudoxus-Callippus, supported by Aristotle, and the theory of epicycles of Apollonius of Perga and Hipparchus. However, the latter was forced to partially abandon the principle of uniform motion, introducing the equant model.

Refusal of geocentrism

During the scientific revolution of the 17th century, it became clear that geocentrism is incompatible with astronomical facts and contradicts physical theory; The heliocentric picture of the world gradually became established. The main events that led to the abandonment of the geocentric system were the creation of the heliocentric system of planetary movements 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.

Geocentrism and religion

Already one of the first ideas opposing geocentrism led to a reaction from representatives of religious philosophy: the Stoic Cleanthes called for bringing Aristarchus to trial for moving the “Hearth of the World”, meaning the Earth; it is unknown, however, whether Cleanthes’ efforts were crowned with success. In the Middle Ages, since the Christian church taught that the whole world was created by God for the sake of man (see Anthropocentrism), geocentrism was also successfully adapted to Christianity. This was also facilitated by a literal reading of the Bible. The scientific revolution of the 17th century was accompanied by attempts to administratively ban this system, which led, in particular, to the trial of the supporter and promoter of heliocentrism Galileo Galilei. Currently geocentrismhow the religious faith is found among some conservative Protestant groups in the United States.

Planet Earth keeps a huge number of secrets, a special place among which is occupied by the mystery of its internal structure. The deepest mines that man has been able to create are only a few kilometers long. Despite the fact that it is impossible to penetrate inside our planet, scientists have been able to create a rough picture of its internal structure.

What is happening inside our planet?

Everything that is in the center of the Earth must be in a molten and liquid state. However, in reality this does not happen, because for every 1 cm 3 of the mantle from the surface of the earth's crust there is a pressure of 13 tons. This is approximately the weight of a KAMAZ loaded with asphalt. Scientists suggest that for this reason the mantle and core may be in a solid state.

If our planet could be cut into two halves, then the layers that are located in the center of the Earth would be visible to us as several circular layers. The first of these is the earth's crust. Its thickness ranges from approximately 20 to 50 km. A type of earth's crust called continental is made of granite. In some places - for example, such as the Grand Canyon - water washed away the upper layer of the earth's crust, and the granite layer became available for study and observation. The earth's crust is also located at the bottom of the oceans, but its thickness is much less - only about 4.5 km. It consists not of granite, but of basalt.

The mantle is the layer next to the Earth's crust

If we move towards the center of our planet, then the mantle will follow the earth's crust. Researchers call this layer “the most powerful.” The thickness of the mantle reaches 3000 km. If a tunnel could be dug through the mantle, it would take 36 hours to travel from one end to the other in a car at a speed of 80 km/h. However, in reality such a journey is impossible. After all, the earth's mantle is a place where enormous temperatures and enormous pressure prevail. Presumably, it consists of lead, magnesium and iron, and the temperature of this layer reaches 2 thousand o C. No one has ever actually seen the mantle - after all, even this gigantic temperature, according to researchers, increases by 1 o C as you move deeper into the mantle. every 30 meters. The mantle also receives a large amount of heat from the core, which has an even higher temperature.

Throughout the history of geology, scientists have wondered what is at the center of the earth. However, until now, knowledge about this part of our planet cannot be called exhaustive. It is reliably known that the upper layers of the mantle consist of rock called peridotite. In turn, peridotite consists of many minerals - olivine, pyroxene, and also garnet, known to all jewelers, which is used to make jewelry.

Center of the planet

Finally, at the very center of the Earth is the core. It is located directly under the mantle. Its diameter is approximately 6400 km. At first glance, the Earth's core, isolated from heat and the sun, should have a very low temperature. However, this area is precisely the place of unimaginable heat. Here the temperature ranges from 2200 to 3300 o C. The Earth's core is liquid, molten metal mixed with sulfur and oxygen. This part of our planet has enormous density, because it is most compressed by the entire mass of the upper layers.

Why do the metals at the center of the Earth have such a high temperature? It is believed that heat has been stored in the core of our planet for 4.6 billion years, since it was formed. However, most of the heat, according to geologists, is the result of radioactive decay processes inside the Earth.

How is the structure of the Earth studied?

How did scientists manage to discover everything that is in the center of the Earth and get an idea of ​​its internal structure? Indeed, in reality, not a single device can reach the center of our planet. First of all, it became possible to draw conclusions about the internal structure of our planet thanks to the study of volcanic eruptions. Hot gas and molten metals burst out from the depths of the Earth during eruptions. Thus, scientists were able to understand what is in the center of the earth. The mystery of the structure of our planet was also solved by studying seismic activity.

Study of seismic activity

At a depth of about 3 thousand km. Seismic waves move differently than on the surface of the planet. Some can suddenly change the direction of their movement, others can suddenly disappear. Colliding with formations that differ in their hardness, seismic waves change their character. Using sensitive equipment, scientists were able to recreate the supposed internal structure of our planet. Such research became possible only thanks to scientific progress and technology development. Once upon a time, humanity was inclined to believe that the Earth was at the center of the Universe and was also flat. However, these naive assumptions have long been refuted. Today, humanity has every opportunity to further explore our mysterious planet, including its internal structure.

People have long known that the Earth is round, and they are finding more and more new ways to show that our world is not flat. And yet, even in 2016, there are quite a few people on the planet who firmly believe that the Earth is not round. These are scary people, they tend to believe in conspiracy theories, and it's hard to argue with them. But they do exist. So is the Flat Earth Society. It becomes funny just thinking about their possible arguments. But the history of our species was interesting and quirky, even firmly established truths were refuted. You don't have to resort to complicated formulas to dispel the flat Earth conspiracy theory.

Just look around and check ten times: the Earth is definitely, inevitably, completely and absolutely not 100% flat.

Today people already know that the Moon is not a piece of cheese or a playful deity, and the phenomena of our satellite are well explained by modern science. But the ancient Greeks had no idea what it was, and in their search for an answer, they made some insightful observations that allowed people to determine the shape of our planet.

Aristotle (who made quite a few observations about the spherical nature of the Earth) noted that during lunar eclipses (when the Earth's orbit places the planet exactly between the Sun and the Moon, creating a shadow), the shadow on the lunar surface is circular. This shadow is the Earth, and the shadow cast by it directly indicates the spherical shape of the planet.

Since the Earth rotates (look up the Foucault pendulum experiment if in doubt), the oval shadow that appears during each lunar eclipse indicates not only that the Earth is round, but also not flat.

Ships and horizon

If you've been in port recently, or just strolled along the beach, looking at the horizon, you may have noticed a very interesting phenomenon: approaching ships don't just "emerge" from the horizon (as they would if the world were flat), but rather emerge from the sea. The reason that ships literally “come out of the waves” is that our world is not flat, but round.

Imagine an ant walking along the surface of an orange. If you look at an orange from a close distance, with your nose to the fruit, you will see how the ant's body slowly rises above the horizon due to the curvature of the orange's surface. If you do this experiment with a long road, the effect will be different: the ant will slowly “materialize” into your field of view, depending on how sharp your vision is.

Change of constellations

This observation was first made by Aristotle, who declared the Earth to be round by observing the change of constellations when crossing the equator.

Returning from a trip to Egypt, Aristotle noted that “stars are observed in Egypt and Cyprus that were not seen in the northern regions.” This phenomenon can only be explained by the fact that people look at the stars from a round surface. Aristotle continued and stated that the sphere of the Earth “is of small size, for otherwise the effect of such a slight change of terrain would not have manifested itself so quickly.”

Shadows and sticks

If you stick a stick into the ground, it will provide shade. The shadow moves as time passes (based on this principle, ancient people invented sundials). If the world were flat, two sticks in different places would produce the same shadow.

But this doesn't happen. Because the Earth is round, not flat.

Eratosthenes (276–194 BC) used this principle to calculate the circumference of the Earth with good accuracy.

The higher you go, the farther you can see

Standing on a flat plateau, you look towards the horizon away from you. You strain your eyes, then take out your favorite binoculars and look through them as far as your eyes can see (using binocular lenses).

Then you climb the nearest tree - the higher the better, the main thing is not to drop your binoculars. And again look, straining your eyes, through binoculars to the horizon.

The higher you climb, the further you will see. Usually we tend to associate this with obstacles on Earth, when you cannot see the forest for the trees, and freedom for the concrete jungle. But if you stand on a perfectly clear plateau, with no obstacles between you and the horizon, you will see much more from above than from the ground.

It's all about the curvature of the Earth, of course, and this wouldn't happen if the Earth were flat.

Flying an airplane

If you've ever flown out of the country, especially somewhere far away, you might have noticed two interesting facts about airplanes and the Earth:

Planes can fly in a relatively straight line for a very long time without falling off the edge of the world. They can also fly around the Earth without stopping.

If you look out the window on a transatlantic flight, most of the time you will see the curvature of the earth on the horizon. The best kind of curvature was on the Concorde, but that plane is long gone. From a new plane, the horizon should be completely curved.

Look at other planets!

The Earth is different from others, and that is undeniable. After all, we have life, and we have not yet found planets with life. However, all planets have similar characteristics, and it would be logical to assume that if all planets behave in a certain way or exhibit specific properties - especially if the planets are separated by distance or formed under different circumstances - then our planet is similar.

In other words, if there are so many planets that formed in different places and under different conditions, but have similar properties, most likely our planet will be one. From our observations, it became clear that the planets are round (and since we knew how they formed, we know why they are shaped that way). There's no reason to think our planet won't be the same.

In 1610, Galileo Galilei observed the rotation of the moons of Jupiter. He described them as small planets orbiting a large planet - a description (and observation) that the church did not like because it challenged the geocentric model in which everything revolved around the Earth. This observation also showed that the planets (Jupiter, Neptune, and later Venus) are spherical and revolve around the Sun.

A flat planet (ours or any other) would be so incredible to observe that it would overturn almost everything we know about the formation and behavior of planets. This will not only change everything we know about the formation of planets, but also about the formation of stars (since our Sun must behave differently to accommodate the flat Earth theory), the speed and movement of cosmic bodies. In short, we don't just suspect that our Earth is round - we know it.

The existence of time zones

This could only be explained by the fact that the Earth is round and rotates around its own axis. At a certain point, when the sun is shining on one part of the Earth, it is dark on the other end, and vice versa. This is where time zones come into play.

Another point. If the sun were a "spotlight" (its light shining directly on a specific area) and the world was flat, we would see the sun even if it wasn't shining above us. In much the same way, you can see the light of a spotlight on a theater stage while remaining in the shadows. The only way to create two completely separate time zones, one of which will always be in the dark and the other in the light, is to have a spherical world.

Center of gravity

There's an interesting fact about our mass: it attracts things. The force of attraction (gravity) between two objects depends on their mass and the distance between them. Simply put, gravity will pull toward the center of mass of objects. To find the center of mass, you need to study the object.

Imagine a sphere. Because of the shape of the sphere, no matter where you stand, there will be the same amount of sphere underneath you. (Imagine an ant walking on a glass ball. From the ant's point of view, the only sign of movement will be the movement of the ant's legs. The shape of the surface will not change at all). The center of mass of a sphere is at the center of the sphere, meaning gravity pulls everything on the surface towards the center of the sphere (straight down), regardless of the object's location.

Let's consider a plane. The center of mass of the plane is at the center, so the force of gravity will pull everything on the surface towards the center of the plane. This means that if you are on the edge of the plane, gravity will pull you towards the center, and not down, as we are used to.

And even in Australia, apples fall from top to bottom, not from side to side.

Photos from space

Over the past 60 years of space exploration, we have launched many satellites, probes, and people into space. Some of them returned, some continue to remain in orbit and transmit beautiful images to Earth. And in all the photographs the Earth (attention) is round.

If your child asks how we know the Earth is round, take the trouble to explain.

The ancient farmer, tied to his piece of land, could not have had a large circle of observation and experience. He judged the world only on the basis of what he directly felt and saw with his own eyes. He believed that the world was divided into two completely different parts - the Earth and the sky.

The earth seemed small and flat to him, above which, like the roof of a house, rose the crystal “firmament of heaven.” Above the “firmament” there are supposedly “upper waters”, which sometimes flow through holes in the sky, by the will of God, onto the Earth in the form of rain. The Sun, Moon and other celestial bodies move across the sky around the Earth.

With such ideas, it was easy to come to the conclusion that everything in the world was created for man, that man is the “crown of creation,” that only for people the Sun, Moon and stars shed their light on the Earth. Moreover, every ancient people not only considered the Earth to be the center of the entire universe, but was inclined to believe that the very place where they lived was the center of the world. For example, the Chinese still call their country the Middle Kingdom; The Incas of Peru said that the center of the world is in the temple of Kutsko, whose name means “navel.” Such a naive, limited, typically geocentric view of the world was fully consistent with direct visual impressions.

In one form or another, we find this view among all the peoples of the ancient world - the Egyptians, Greeks, etc. Even Babylonian astronomy, despite its rather high development, still did not come to a new, more correct view of the sky and Earth, on structure of the universe. In the oldest Babylonian writings we read that the Earth has the appearance of a convex island surrounded by an ocean, and the sky is simply a solid dome resting on the earth's surface. The celestial bodies are attached to this dome, and it separates the waters “below” (the ocean flowing around an island on earth) from the waters “above” (rainwater). The sun rises in the morning, leaving the heavenly gate, and in the evening, when setting, it passes through the western gate and moves somewhere underground at night.

This primitive view of the structure of the entire world was not subject to any change in Babylon, despite the continued development of the science of the sky. But this will not surprise us if we remember that Babylonian (like Egyptian, etc.) astronomy was the science of the priests. It was only an auxiliary tool for compiling a calendar and developing a cult ritual and remained entirely captive of religious ideas inextricably linked with the anthropogeocentric worldview.

The Babylonian view of the universe influenced the biblical description of the world. In European-Christian sacred books, the view is everywhere held that the Earth plays an exceptional role in the whole world, which was created and exists only for man. About the heavens in the Bible, for example, it is said that they are “solid as a cast mirror” (Book of Job, XXXVII, 18) and that they are established on columns - “the earth shook, the foundations of the heavens trembled and moved” (Second Book of Kings, XXII, 8 ), “the pillars of heaven tremble” (book of Job, XXVI, 41). As for the question of what the Earth rests on, the same “sacred” book of Job in different places gives contradictory ideas: the Earth is established on some foundation - “where were you when I laid the foundation of the Earth”, “on what are they established its foundations and who laid the cornerstone" (XXXIX, 4, 6), then a different view emerges - "he spread the north over the void, hung the Earth on nothing" (XXVI, 7).

The idea of ​​the exceptional position of the Earth in the world underlay not only every religion, but also astrology, which believed that by the movement of the planets and their position among the zodiacal constellations, one can predict the future of nations, the fate of individuals, etc.

The enormous, comprehensive influence of the Sun on all processes occurring on Earth, on the life of plants and animals, was noticed very early by people. It was also found long ago that the time of year can be determined by the position of the stars in the sky, and therefore it seemed that, for example, the harvest depended on the stars, and not just on the Sun. All this ultimately led to the idea that all earthly events depend on the occurrence of certain celestial phenomena and that, therefore, all events in human life can be predicted from the celestial bodies. Therefore, in ancient Egypt, Babylon, Assyria and other ancient countries, astrology was very popular. Astrologer-priests made observations of the heavenly bodies not only for the calendar, but also for astrological fortune-telling.

The Christian Church in the first centuries was unfriendly to astrology or stargazing, as a “pagan teaching” that recognized predestination and, therefore, contradicted the idea of ​​​​free will and responsibility for sins. However, during the Renaissance, astrology became widespread in Western Europe and even became a compulsory subject of teaching in a number of universities, which was in complete harmony with the anthropogeocentric worldview.

If the Earth, as the abode of the “crown of creation” - man, occupies a special position in the universe, and the heavenly bodies are created only for the Earth and its inhabitants, then, according to astrologers, it can be assumed that the planets (astrologers also included the Sun and Moon among the planets) influence everything that happens on Earth and the fate of individual people. Therefore, under kings, generals, etc., there was a special position of an astrologer who compiled horoscopes, i.e., predictions of future events based on the location of the planets among the constellations at the time of a person’s birth and at other important moments in his life. Astrology and astronomy were closely related at that time, with astrology being the source of livelihood for astronomers. Moreover, both were based on the same anthropogeocentric idea of ​​the world.

This naive idea fully satisfied the needs of ancient agriculture, hunting, fishing and navigation, while people's experience was limited.

Already in ancient times, man was faced with the question: where does the Sun go after setting in the west? As we have seen, the Babylonians, who saw the sky as a solid hemisphere, believed that the Sun rose in the morning through the eastern “heavenly gate” and set in the evening through the western one. Thales, Anaximander and other Greek thinkers who lived between 600-500. until hr. era in the Ionian cities on the shores of Asia Minor, were no longer limited to the old question: what is above us and around us? They took a new path, posing another question: what is beneath us?

From the observation that some stars do not set, but describe a complete circle above the horizon, while others plunge below it and rise again, they broke away from visible impressions and came to the conclusion that the sky is spherical. But if this is so, if in addition to one dome-shaped “ceiling” above the Earth there is also a hemisphere below it, that is, if the sky has the shape of a complete sphere, then there is nothing to talk about “heavenly gates”. From this point of view, it is necessary that the spherical, spherical sky rotate around an axis, due to which the rising and setting of the luminaries occurs. It followed that the Earth does not lie on anything, but is isolated on all sides in space, and when the Sun; sets in the west, it describes the second half of its circular path on the invisible part of the celestial sphere.

However, the view continued to exist that the Earth was flat, that it was a disk or a thin cylinder, on the upper surface of which people lived. Anaximander (610-547 BC) made a very important amendment to this idea: he mentally increased the size of the celestial sphere and reduced the size of the Earth, so that the naive, primitive idea of ​​the Earth being limited by the sky disappeared. It thus turned out that the flat Earth, surrounded by an air shell, hangs freely in space, that equally distant from every point of the celestial sphere of almost infinite dimensions, it cannot fall either up or down and therefore remains in “equilibrium” in the center of the whole world . Of course, for a long time this idea of ​​Anaximander seemed dizzying, since it broke with the usual ideas.

After the whole world began to appear as a sphere, a further step was taken: ideas appeared that the Earth was not a flat disk or a cylinder, but a sphere. After all, if the Earth is flat, then the horizon should be the same in all places, and as a result of this, the view of the starry sky should be the same everywhere, while earthly objects from any point should be visible entirely from top to bottom. Meanwhile, Greek navigators noticed that the stars rising above the southern part of the horizon off the coast of Africa were not visible at all off the coast of the Black Sea, that is, in more northern countries; this indicated that the Earth has a curved surface and that the position of the horizon is different in different places. At the same time, the Greeks living on the islands and sailing the seas could not help but pay attention to the fact that when approaching the shore, the tops of high objects (mountains, ships, buildings, etc.) are first visible, then the middle ones and finally the lower ones; this led to the idea that the Earth should have some kind of convexity, shielding the lower parts of objects from us.

The founder of the doctrine that the Earth is a ball hanging freely in cosmic space is considered to be Pythagoras, a philosopher and mathematician of the 6th century BC. era. In terms of its significance and boldness, this idea can be placed on a par with the doctrine of the movement of the Earth or with the discovery of the law of universal attraction. In any case, it is one of the greatest achievements of scientific thought of antiquity in general.

Then the question arose about the size of the spherical Earth. This question was first solved, and in an amazingly simple way, by the Greek scientist Eratosthenes (276-196 BC). Eratosthenes established that on the day of the summer solstice in Alexandria, at noon, the Sun was 7.2° from the zenith (from the highest point of the sky), i.e., one fiftieth of a circle. On the same day, further south, in Siena (now here is the city of Assouan), lying on the same meridian with Alexandria, the Sun illuminated the bottom of the wells, i.e. there the Sun was exactly at its zenith, directly overhead. These two cities are 5,000 stadia apart. Therefore, Eratosthenes believed that if this distance is one fiftieth of the circumference of the globe, then its entire circumference is 250,000 stadia.

Having put forward the idea of ​​the spherical shape of the firmament, the Ionian philosophical school, represented by Anaximander, took the first step along the path of renunciation of direct impressions. By the way, one of the representatives of this school, Anaximenes (VI century BC), considered the celestial sphere to be solid and transparent, and therefore invisible. According to this philosopher, which dominated the minds of people for a very long time, the heavenly “firmament” rotates around an axis, and the stars are driven into it like golden nails. However, one of the most remarkable representatives of the Ionian school, Anaxagoras (500-428 BC), completely rejected the idea of ​​\u200b\u200battaching the celestial bodies to a solid, crystalline vault of heaven. He considered the stars to consist of the same matter as the Earth, namely rocky masses, some of which are incandescent and luminous, while others are cold and dark. In connection with this idea of ​​\u200b\u200bthe unity of earthly and celestial matter, Anaxagoras said that the Sun consists of molten substance similar to terrestrial matter. To support this, Anaxagoras cited meteorites falling from the sky as an example. He described one “heavenly stone” that fell in his time in Thrace and was equal in size to a millstone. He believed that this piece of iron, which fell to the Earth in daylight, originated from the Sun. This allegedly proves that our daylight consists of hot iron.

Anaxagoras, further, argued that the Sun is many times larger in size than the entire Peloponnese, and the Moon is approximately equal to the Peloponnese. The moon is so large that mountains and valleys fit on it, and - like the Earth - it is the habitat of living beings; This dark body receives its light from the Sun; it is eclipsed when it falls into the shadow cast by the Earth. It is characteristic that the question: if celestial bodies, like terrestrial bodies, are heavy, then why don’t they fall to Earth? - Anaxagoras replied that the reason for this was their circular motion around the Earth. This means, from the point of view of this thinker, celestial bodies do not fall to Earth because their circular motion outweighs the force of the fall, which pulls the bodies down. In this regard, he compared the movement of the Moon around the Earth with the movement of a stone in a sling, the rapid rotation of which destroys the desire of the stone to fall to the Earth (this is probably the oldest concept of centrifugal force that has come down to us).

For a long time, Anaxagoras hid these views of his or expressed them only to his closest students. When these views became known thanks to the dissemination of his work “On Nature” (only a few excerpts have come down to us), he became a victim of obscurantism - he was imprisoned as an atheist and sentenced to death on charges of daring to establish laws deity, and the Sun is considered not a divine luminary, but a red-hot stone, a hot meteorite. Only thanks to the urgent efforts of his powerful student and friend Pericles, the death penalty for Anaxagoras was replaced by exile from his native country: he was released with the obligation to leave Athens forever.

Determination of the circumference of the Earth according to Eratosthenes. At the moment of observation made by Eratosthenes, the rays of the Sun at point S - Syene are directed towards the center of the Earth, as a result of which a vertically placed rod does not cast a shadow. At the same time, at point A - Alexandria, located on the same meridian, the sun's rays form an angle a equal to 7.2° with the direction to the center of the Earth AO, i.e., corresponding to 1/50 of a circle. Due to the parallelism of the sun's rays, angle a is equal to angle b, and the latter corresponds to AS, which is equal to the distance between both cities and is 1/50 of the circumference of the Earth.

As can be seen from the above, even in those distant times, Anaxagoras expressed basically correct views about the Earth, the Sun, stars, meteorites, centrifugal force, etc. The following is especially important.

Anaxagoras believed that all modifications of bodies are nothing more than the connection or separation of the smallest particles of matter invisible to the eye. He wrote: “Nothing is created again or destroyed; everything comes down to the combination or separation of things that have existed from time immemorial; It would be more accurate to recognize origination as combination, and cessation as separation.”

This idea of ​​matter undoubtedly influenced the great ancient Greek materialist Democritus (460-370 or 360 BC), who developed the atomic theory of the world, which played a colossal role in the development of natural science and philosophy.

According to this theory of Democritus, the universe is beginningless and was never created by anyone; everything that was, is and will be is determined by necessity, depends on certain reasons, and not on the whim of some supernatural, divine beings. The Universe consists of indivisible, qualitatively identical smallest particles - atoms, which are in continuous motion from eternity. Atoms, differing in shape, change their relative positions, and for this to be possible, space must be completely empty. Any modification is caused by a change in the relative position of atoms, so that the variety of things depends on the number, shape and combination of atoms. The number of atoms is infinitely large and their shapes are infinitely different, but qualitatively these particles are completely identical. When moving in infinite space, they collide, and this causes vortices from which celestial bodies and various worlds are formed. Democritus taught that in infinite space an infinite number of combinations of atoms can form an infinite number of worlds.

In general, Democritus painted the following picture of the universe: the universe is infinite, its matter is eternal, and the number of worlds is countless, some of the worlds are similar to each other, others are completely different. These bodies are not permanent; they arise and disappear, we see them in various stages of development. Democritus took the whitish shimmering stripe in the sky, since ancient times called the Milky Way, for the accumulation of a colossal number of very closely spaced stars. He called the stars very distant suns; He said about the Moon that it is similar to the Earth, has mountains, valleys, etc.

“Father of the Church” Hippolytus (about 220 AD), in his work “Refutation of All Heresies,” sets out Democritus’s idea of ​​the universe as follows: “The worlds (according to Democritus) are countless and varied in size. In some of them there is neither sun nor moon, in others the sun and moon are larger in size than ours, and in some there are a greater number of them. The distances between the worlds are not equal, between some they are large, between others they are smaller, and some worlds are still growing, others are already in bloom, others are collapsing, and at the same time, worlds arise in some places and are destroyed in others. They die from each other, colliding with each other. Some worlds have no animals and plants and are completely devoid of moisture... Our world is in its prime, no longer able to accept anything from the outside.”

Thus, Democritus did not see a significant difference between our world and other worlds. The earth for him is only one of an infinite number of worlds, that is, only one of the cosmic bodies. Democritus tried to explain that the Earth arose from the condensation of atoms in the center of the world vortex, formed as a result of constant collisions of atoms. He believed that in the beginning the Earth was small and light and therefore was in motion; over time, it became larger and heavier - which is why it went into a stationary state and only began to rotate around its axis.

Although, according to Democritus, the Earth is at the center of the universe, his entire teaching about the nature of stars, the formation of worlds, etc. is completely irreconcilable with the essence of the geocentric worldview.

The views of Democritus were clearly atheistic, and therefore they were considered “dangerous” for the masses. To prevent their spread, aristocrats and reactionaries did not hesitate in their means. For example, Plato and his students bought up the works of Democritus and destroyed them (only minor excerpts from them have reached us). As a result, the bold materialistic ideas of Democritus had only a minor influence in the era in which they arose.

These ideas were used and developed by the outstanding thinker Epicurus (341-270 BC) - one of the pillars of ancient materialism. This philosopher defended the doctrine of the innumerability of worlds and clearly showed that from this doctrine the idea of ​​the spatial infinity of the universe necessarily follows.

Epicurus deduced the infinity of the universe from the fact that “universe” means “all-containing,” so that outside of it there is nothing and cannot be. He argued: “The Universe is infinite, space has neither bottom nor top, nor any end; the universe is infinite because everything limited has something outside itself; the external, after all, presupposes another next to itself, with which it could be compared, but precisely such another is not next to the universe and therefore cannot be compared with anything. Thus, there is nothing external, and therefore the universe has no boundaries - therefore it is infinite and unlimited."

The great Roman poet Lucretius Carus (99-55 BC), an ardent follower of Epicurus, approached this issue in the same way, who in his philosophical poem “On the Nature of Things” outlined the basic ideas of ancient materialism. In this atheistic work, Lucretius says: “If we must admit that there is nothing beyond the universe, it has no edges and no end or limit. And it doesn’t matter what part of the universe you are in: wherever you are, everywhere, from the place you occupy, it remains infinite in all directions.” By the way, Lucretius correctly emphasized the fact that from the idea of ​​​​the infinity of world space, the denial of the idea of ​​​​the central position of the Earth or any other point in the universe logically follows. He wrote: “... do not believe the statement that everything rushes towards some center of the universe,” because “... the universe has no center anywhere, since it has no end.”

If ancient natural philosophy put forward the doctrine of the innumerability of worlds and the spatial infinity of the universe, then ancient astronomy, on the contrary, tried to further establish geocentrism and, therefore, supported the doctrine of the spatial finitude of the universe. In connection with this contradiction, natural philosophers-materialists and practical astronomers usually simply completely ignored each other, without even trying to reconcile their different points of view. The losers, however, were the materialists, although their ideas were never completely forgotten in the ancient world. But these ideas, which refuted the religious worldview, could not achieve such a spread as the idealistic philosophy developed by Socrates, Plato and Aristotle. These philosophers had a huge influence on the subsequent development of thought, but they did not contribute to the progress of our knowledge of the universe, since they set certain limits for science. For example, Socrates (469 - 399 BC) strictly commanded his students not to deal with questions about the movement of the heavenly bodies, their distances from the Earth, their origin, etc., considering these questions unsolvable. According to him Xenophon’s favorite student, he assured that “all this will forever remain a mystery to a mortal, and, of course, the gods themselves are saddened to see man’s efforts to unravel what they wanted to forever hide from him with an impenetrable veil.”

From the point of view of the progress of the natural scientific worldview, the ancient Greek idealistic philosophy, which reached its highest development in the teachings of Aristotle, was undoubtedly a step back in comparison with the teachings of Democritus. This philosophy, by its very essence, served as a justification for a religious worldview. It was clothed with a thick shell of animism, extreme anthropomorphism, naive teleology and other attributes of priesthood (which is why it was used by Christian theologians).

The hypothesis of Professor Kirill Pavlovich Butusov states that our beautiful inhabited Earth may have a cosmic twin. Indeed, we may not be the only living beings in the solar system. If our twin planet exists, then this could explain the frequent visits of UFOs to our Earth. Extraterrestrial civilizations may well exist on a hypothetical planet like Gloria. This is what will be discussed in this article.

Anti-Earth - as it was described in ancient times

The ancient Egyptian sages thought that each of us has a personal astral twin. Hypotheses about doubles in Egypt were especially popular. Moreover, the very concept of “double” came from there. Perhaps it was the ancient Egyptians who were the first to suggest that our Earth has a copy.

Some Egyptian frescoes contained strange images that confirmed the hypothesis described above: in the center of the circle was the celestial body - the Sun, on one side of it was the Earth, and on the other - our twin planet. These planets were connected by a straight line through the star. Near each of them was depicted the likeness of a person. These drawings tell us that ancient Egyptian artists knew not only about the twin of our Earth, but also that extraterrestrial life was present on this planet. Perhaps representatives of an extraterrestrial civilization from a twin planet were deities who are often described in all ancient religious manuscripts. The inhabitants of the Earth's twin could periodically visit our planet, passing on knowledge to their primitive relatives.

There is another version of what the Egyptians tried to portray in the manner described above. They could simply indicate the process of transition of the soul of the deceased to a parallel world.

In addition to the Egyptians, the Pythagoreans were interested in the Earth's twin. For example, G. Syracuse even came up with a name for such a space object - he called it Antichthon. Even in such ancient times, without technology, people knew that our Earth was not alone in the Universe. They believed that it was surrounded by many planets, among which there were inhabited twins of the Earth.

F. Krotonsky at one time presented an interesting hypothesis about the structure of the Universe. In its center he placed the Source of Fire, which he considered the main cosmic luminary and called Hestnia. In the outer limit of space, according to the scientist named above, our Sun was located, which only reflected the light and heat of the Source like a large mirror. Between these luminaries he placed about a dozen planets, among which was the Earth and its twin.

Anti-Earth Gloria was sometimes noticed by astronomers

Of course, many people are now skeptical about the ideas of ancient “experts” in the field of astronomy, since people previously believed that the planet was flat and stood on three pillars. Not all such theories and hypotheses have been confirmed in modern times, but most of them deserve attention, since they turned out to be plausible. The twin of our planet was named Gloria relatively recently. At different times it was called differently. Data about anti-Earth first appeared in the seventeenth century.

It was then that an employee of an observatory located in Paris observed an unknown space object resembling a planet near Venus. The name of this great astronomer is Giovanni Cassini.

The unknown object in outer space seemed crescent-shaped to the astronomer, just like the planet Venus itself at that time. Therefore, Cassini assumed that he had noticed a satellite body of the above planet. The most interesting thing is that the subsequent study of the planet Venus did not allow us to detect this mysterious satellite, so modern scientists have suggested that at one time Cassini observed Gloria, the Earth’s twin.

A few decades later, Gloria was noticed by an astronomer from England, James Short. He saw the anti-Earth in approximately the same place as Cassini. After James, the “non-existent” satellite of Venus was recorded by a specialist astronomer from Germany named Johann Mayer.

After this, the mysterious cosmic body disappeared again, and has not yet been noticed. All of the above astronomers were famous and conscientious, so they could not be wrong. All of them at various times spoke about Gloria, but the rest of the scientific world did not listen to them.

Why have modern astronomers, equipped with super-powerful equipment, been unable to prove the existence of Gloria? It is assumed that the reason for this is the location of the Earth's twin - Gloria may be located behind the Sun in an area invisible from our planet. By the way, the star hides from us a huge part of space, the diameter of which exceeds six hundred similar sizes to our Earth. As for research orbital technology, it is often built on a specific object, which it continuously monitors, so it does not record other objects.

If Gloria exists, what does she look like?

Some experts suggest that the anti-earth consists largely of dust and fragments of various cosmic bodies, collected in a heap using gravity. If this is true, then it should have a low density. Most likely, this planet is very heterogeneous. It may be much hotter there than on Earth. Its surface may be covered with holes, like those on the Moon. Its atmosphere can be very rarefied. If there is some kind of extraterrestrial life on Gloria, then it simply must have water. Some astronomers believe that Gloria is covered with oceans. If this is not so, then there cannot be life on it.

If the amount of liquid on Gloria is minimal, then there may well be primitive life forms on it. If there is more water on Gloria, then more complex living forms can develop there.

According to mythology, Gloria copies our Earth in everything. This means that a developed extraterrestrial civilization must be present on it. Thus, the frequent appearance of UFOs on our planet can be explained. Extraterrestrial beings fly to us, considering us their neighbors, and we, in turn, only guess about their existence.