Earth as a planet in the solar system briefly. Ancient and modern exploration of the Earth. “Earth is a planet of the solar system”

A planet is a body orbiting a star, glowing with light reflected from it and having a size larger than that of asteroids, this definition was consistent with our previous ideas. But a number of discoveries in the 1990s. made him insolvent. Beyond Neptune's orbit, in the Kuiper Belt, astronomers have found hundreds of very large icy bodies. Near some stars, planets were discovered whose orbits were different from others in the solar system. Brown dwarfs and planetary bodies have also been discovered, drifting lonely through dark interstellar space.

In August 2006, the International Astronomical Union (IAU) concluded that a planet is an object that orbits a star and is so large that it has assumed a spheroidal shape and “has no neighbors of comparable mass near its orbit.” This definition removed Pluto from the list of planets, changing our attitude to the structure of both the Solar and other planetary systems formed by accretion in rotating disks. Small particles stick together to form large formations, the mutual attraction of which causes them to unite again and again. As a result, several massive bodies (planets) and many small bodies (asteroids and comets) are formed, representing the remnants of the substance from which the planets were formed. Thus, the term "planet" designates a specific class of celestial bodies.

What is the solar system? What does the solar system consist of? The sun and all the bodies revolving around it form the SOLAR SYSTEM. The solar system includes nine large planets: MERCURY, VENUS, EARTH, MARS - these are terrestrial planets; JUPITER, SATURN, URANUS, NEPTUNE are giant planets; AND PLUTO. The solar system also includes SATELLITES of these planets and MINOR PLANETS, they are also called asteroids, and COMETS.

In ancient times, people noticed a pale luminous stripe in the night sky stretching across the entire sky. She reminded them of spilled milk. According to legend, this is the merit of Hera, who descended to Earth. The luminous stripe was called the Milky Way. Then, much later, thanks to the observations of Galileo, it became known that Milky Way- this is a lot of distant and therefore dim stars. They merge into one dim glow. Then a hypothesis arose that the Sun and all visible stars, including the stars of the Milky Way, belong to one huge system. Such a system was called the Galaxy (written with a capital letter). The name was given precisely in honor of the Milky Way: the word “Galaxy” comes from the ancient Greek concept meaning “milk road”. Galaxy The name of our Galaxy is also trivial - the Milky Way

But it is not always easy to judge the building you are inside. It’s the same with our Galaxy: there were very long debates about its size, mass, and structure of stars. Only relatively recently, in the twentieth century, all kinds of research allowed a person to judge all this. We were greatly helped by the fact that our Galaxy is not alone. Our Universe is usually defined as the totality of everything that physically exists. This is the totality of space and time, all forms of matter, physical laws and constants that govern them. However, the term Universe can also be interpreted differently, as space, world or nature.

Why does the Earth rotate? Everyone knows that our planet rotates around its axis, it in turn rotates around the sun, and the sun, together with the planets, rotates around the center of our galaxy. Now think about why? Where is the force that makes this whole carousel rotate? It has now been established that the speed of rotation of the earth around its axis is gradually decreasing. It would seem that this is the answer to the question. Previously, the earth was “spinned” and now it rotates by inertia. But calculations show that with such an approach it would have stopped long ago. The same question arises about the sun, why does it rotate, and even carry all the planets with it? Latest research space allowed us to draw conclusions about the presence of massive black holes in the centers of galaxies. There is a huge black hole at the center of our galaxy. Judging by the fact that all the stars in the galaxy revolve around its center, it can be assumed that the culprit of the rotation is a massive black hole. But the question again remains unanswered: why does a black hole rotate? The most interesting thing is, where do they all get the energy for this rotation? After all, no one has canceled the law of conservation of energy, and the expenditure of this energy must be simply colossal.

What is the Moon? Earth and Moon in comparison. The Earth's satellite, the Moon, makes one revolution around the Earth in the same time it takes it to make one revolution around its axis. That's why we always see only one side of the Moon. Reverse side Our satellite was seen for the first time only in 1959, when an automatic space station flew around the Moon and took photographs. The lunar globe is approximately four times smaller than the Earth's. But the earth is much denser and heavier than the moon.

South Pole the point at which the Earth's imaginary axis of rotation intersects its surface in the Southern Hemisphere.EarthSouthern Hemisphere The South Pole is located within the Polar Plateau of Antarctica at an altitude of 2800 meters. The ice thickness at the South Pole is 2840 meters. The average annual air temperature is 48.9 °C (maximum 14.7 °C, minimum 74.3 °C).Antarctic Polar Plateau meters Amundsen-Scott Station (South Pole)

The North Pole is the point at which the Earth's imaginary axis of rotation intersects its surface in the Northern Hemisphere. The North Pole is located in the central part of the Arctic Ocean, where the depth does not exceed 4000 m. All year round In the area of the North Pole, powerful multi-year pack ice drifts. The average temperature in winter is about 40 °C, in summer it is mainly about 0 °C. In September 2007, record low ice levels were recorded at the North Pole. According to specialists from the National Data Center for Snow and Ice Research, in 2008, the Arctic ice of the pole may completely melt. Nevertheless, the world has already welcomed 2009, but the ice remains in place.

The equator is a line of section of the earth's surface by a plane passing through the center of the Earth, perpendicular to the axis of its rotation. The length of the equator is km. Along the equator, day is always equal to night. The equator divides the globe into the Northern and Southern Hemispheres. The equator serves as the beginning of counting geographical latitude(equator latitude - 0 degrees). lat.Aequator - equalizer

Planets are celestial bodies orbiting a star. They, unlike stars, do not emit light and heat, but shine with the reflected light of the star to which they belong. The shape of the planets is close to spherical. Currently, only the planets are known with certainty solar system, but it is very likely that other stars also have planets.

Gilbert expressed a hypothesis about terrestrial magnetism: The Earth is a large spherical magnet, the poles of which are located near the geographic poles. He substantiated his hypothesis with the following experiment: if you bring a magnetic needle closer to the surface of a large ball made of a natural magnet, then it is always set in a certain direction, like a compass needle on Earth. Naydysh V.M. 2004 KSE

Our Earth is one of the 8 major planets revolving around the Sun. It is in the Sun that the bulk of the matter in the Solar System is concentrated. The mass of the Sun is 750 times the mass of all the planets and 330,000 times the mass of the Earth. Under the influence of its gravity, the planets and all other bodies of the solar system move around the Sun.

The distances between the Sun and the planets are many times greater than their sizes, and draw a diagram in which the single scale for the Sun, planets and the distances between them is almost impossible. The diameter of the Sun is 109 times greater than that of the Earth, and the distance between them is approximately the same number of times greater than the diameter of the Sun. In addition, the distance from the Sun to the last planet of the solar system (Neptune) is 30 times greater than the distance to Earth. If we depict our planet as a circle with a diameter of 1 mm, then the Sun will be at a distance of about 11 m from the Earth, and its diameter will be approximately 11 cm. The orbit of Neptune will be shown by a circle with a radius of 330 m. Therefore, they usually do not modern scheme Solar system, but only a drawing from Copernicus’s book “On the Circulation of the Heavenly Circles” with other, very approximate proportions.

According to their physical characteristics, large planets are divided into two groups. One of them - the terrestrial planets - consists of the Earth and similar Mercury, Venus and Mars. The second includes the giant planets: Jupiter, Saturn, Uranus and Neptune. Until 2006, Pluto was considered the furthest major planet from the Sun. Now it, along with other objects of similar size - long-known large asteroids and objects discovered on the outskirts of the Solar System - is classified as a dwarf planet.

The division of planets into groups can be traced according to three characteristics (mass, pressure, rotation), but most clearly - according to density. Planets belonging to the same group differ only slightly in density, while the average density of terrestrial planets is approximately 5 times greater than the average density of giant planets.

Earth ranks fifth in size and mass among the major planets, but is the largest of the terrestrial planets, which includes Mercury, Venus, Earth and Mars. The most important difference between the Earth and the other planets of the solar system is the existence of life on it, which reached its highest, intelligent form with the advent of man. Conditions for the development of life on the bodies of the solar system closest to Earth are unfavorable; inhabited bodies outside the latter have also not yet been discovered. However, life is a natural stage in the development of matter, therefore the Earth cannot be considered the only inhabited cosmic body of the Universe, and terrestrial life forms cannot be considered its only possible forms.

According to modern cosmogonic concepts, the Earth was formed approximately 4.5 billion years ago by gravitational condensation from gas and dust matter scattered in the circumsolar space, containing all known in nature chemical elements. The formation of the Earth was accompanied by differentiation of matter, which was facilitated by the gradual heating of the Earth's interior, mainly due to the heat released during the decay of radioactive elements (uranium, thorium, potassium, etc.). The result of this differentiation was the division of the Earth into concentrically located layers - geospheres, differing in chemical composition, state of aggregation And physical properties. The Earth's core formed in the center, surrounded by a mantle. From the lightest and most fusible components of the substance released from the mantle during melting processes, the earth's crust located above the mantle arose. The collection of these inner geospheres, bounded by the solid surface of the earth, is sometimes called the “solid” Earth (although this is not entirely accurate, since the outer part of the core is found to have the properties of a viscous fluid). The “solid” Earth contains almost the entire mass of the planet.

physical characteristics The Earth and its orbital motion have allowed life to persist over the past 3.5 billion years. According to various estimates, the Earth will maintain conditions for the existence of living organisms for another 0.5 - 2.3 billion years.

The earth interacts (is attracted gravitational forces) with other objects in space, including the Sun and Moon. The Earth revolves around the Sun and makes a complete revolution around it in approximately 365.26 solar days - a sidereal year. The Earth's rotation axis is inclined by 23.44° relative to the perpendicular to its orbital plane, this causes seasonal changes on the planet's surface with a period of one tropical year - 365.24 solar days. A day is now approximately 24 hours long. The Moon began its orbit around the Earth approximately 4.53 billion years ago. The Moon's gravitational effect on Earth causes ocean tides. The Moon also stabilizes the tilt of the Earth's axis and gradually slows down the Earth's rotation. Some theories suggest that asteroid impacts caused significant changes in environment and the surface of the Earth, causing, in particular, mass extinctions various types Living creatures. http://ru.wikipedia.org/wiki/%C7%E5%EC%EB%FF

The earth, as mentioned earlier, has a shape close to spherical. The radius of the ball is 6371 km. The Earth revolves around the Sun and rotates on its axis. There is one natural satellite orbiting the Earth - the Moon. The moon is located at a distance of 384.4 thousand km from the surface of our planet. The periods of its revolution around the Earth and around its own axis coincide, so the Moon only faces the Earth, and the other side is not visible from the Earth. The Moon does not have an atmosphere, so the side facing the Sun has a high temperature, and the opposite, darkened side has a very low temperature. The surface of the Moon is heterogeneous. The plains and mountain ranges on the Moon are intersected by cracks.

The Earth, like other planets in the Solar System, has early phases of evolution: the accretion phase (birth), melting of the outer sphere globe and the phase of the primary crust (lunar phase). A.P. Sadokhin KSE chapter 5 page 131 The difference between our planet and others is that almost all the planets were not caught lunar phase, and if it did exist, it either did not end or passed without results, because only on Earth did bodies of water (oceans) appear in which a combination of substances could occur for the future development of the planet.

Abstract on the topic

“Earth is a planet of the solar system”

1. Structure and composition of the Solar system. Two groups of planets

2. Terrestrial planets. Earth–Moon system

3. Earth

4. Ancient and modern exploration of the Earth

5. Exploring the Earth from space

6. The emergence of life on Earth

7. The only satellite of the Earth is the Moon

Conclusion

1. Structure and composition of the Solar system. Two groups of planets.

The distances between the Sun and the planets are many times greater than their sizes, and it is almost impossible to draw a diagram that would maintain a single scale for the Sun, planets and the distances between them. The diameter of the Sun is 109 times greater than that of the Earth, and the distance between them is approximately the same number of times greater than the diameter of the Sun. In addition, the distance from the Sun to the last planet of the solar system (Neptune) is 30 times greater than the distance to Earth. If we depict our planet as a circle with a diameter of 1 mm, then the Sun will be at a distance of about 11 m from the Earth, and its diameter will be approximately 11 cm. The orbit of Neptune will be shown as a circle with a radius of 330 m. Therefore, they usually do not give a modern diagram of the Solar system, but only a drawing from Copernicus’s book “On the Revolution of the Heavenly Circles” with other, very approximate proportions.

According to their physical characteristics, large planets are divided into two groups. One of them - the terrestrial planets - consists of the Earth and similar Mercury, Venus and Mars. The second includes the giant planets: Jupiter, Saturn, Uranus and Neptune. Until 2006, Pluto was considered the furthest major planet from the Sun. Now it, together with other objects of similar size - long-known large asteroids (see § 4) and objects discovered on the outskirts of the Solar system - is classified as a dwarf planet.

Most of the mass of the terrestrial planets comes from solid matter. The Earth and other terrestrial planets consist of oxides and other compounds of heavy chemical elements: iron, magnesium, aluminum and other metals, as well as silicon and other non-metals. The four most abundant elements in the solid shell of our planet (lithosphere) - iron, oxygen, silicon and magnesium - account for over 90% of its mass.

The low density of the giant planets (for Saturn it is less than the density of water) is explained by the fact that they consist mainly of hydrogen and helium, which are mainly in gaseous and liquid states. The atmospheres of these planets also contain hydrogen compounds - methane and ammonia. Differences between the planets of the two groups arose already at the stage of their formation (see § 5).

Of the giant planets, Jupiter is the best studied, on which even with a small school telescope numerous dark and light stripes are visible, stretching parallel to the planet’s equator. This is what cloud formations look like in its atmosphere, the temperature of which is only -140 °C, and the pressure is approximately the same as at the surface of the Earth. The reddish-brown color of the stripes is apparently explained by the fact that, in addition to the ammonia crystals that form the basis of the clouds, they contain various impurities. In the photographs taken spacecraft, traces of intense and sometimes persistent atmospheric processes are visible. Thus, for over 350 years, an atmospheric vortex has been observed on Jupiter, called the Great Red Spot. In the earth's atmosphere, cyclones and anticyclones exist on average for about a week. Atmospheric currents and clouds have been recorded by spacecraft on other giant planets, although they are less developed than on Jupiter.

Structure. It is assumed that as it approaches the center of the giant planets, hydrogen, due to increasing pressure, should pass from a gaseous to a gas-liquid state, in which its gaseous and liquid phases coexist. At the center of Jupiter, the pressure is millions of times higher than the atmospheric pressure that exists on Earth, and hydrogen acquires properties characteristic of metals. In the interior of Jupiter, metallic hydrogen, together with silicates and metals, forms a core that is approximately 1.5 times larger in size and 10–15 times larger in mass than the Earth.

Weight. Any of the giant planets exceeds in mass all the terrestrial planets combined. The largest planet in the solar system - Jupiter is larger than itself major planet terrestrial group - the Earth is 11 times in diameter and more than 300 times in mass.

Rotation. The differences between the planets of the two groups are manifested both in the fact that the giant planets rotate faster around their axis and in the number of satellites: for 4 terrestrial planets there are only 3 satellites, for 4 giant planets there are more than 120. All these satellites consist of the same substances like terrestrial planets - silicates, oxides and sulfides of metals, etc., as well as water (or water-ammonia) ice. In addition to numerous craters of meteorite origin, tectonic faults and cracks in their crust or ice cover were discovered on the surface of many satellites. The most surprising thing was the discovery on the closest moon to Jupiter, Io, of about a dozen active volcanoes. This is the first reliable observation of terrestrial-type volcanic activity outside our planet.

In addition to satellites, giant planets also have rings, which are clusters of small-sized bodies. They are so small that they are not visible individually. Thanks to their orbit around the planet, the rings appear solid, although through the rings of Saturn, for example, both the surface of the planet and the stars are visible. The rings are located in close proximity to the planet, where large satellites cannot exist.

2. Terrestrial planets. Earth–Moon system

Due to the presence of a satellite, the Moon, the Earth is often called a double planet. This emphasizes both their common origin and the rare ratio of the masses of the planet and its satellite: the Moon is only 81 times smaller than the Earth.

Sufficiently detailed information will be given about the nature of the Earth in subsequent chapters of the textbook. Therefore, here we will talk about the rest of the terrestrial planets, comparing them with ours, and about the Moon, which, although it is only a satellite of the Earth, is by its nature a planetary type body.

Despite the common origin, the nature of the Moon differs significantly from that of the Earth, which is determined by its mass and size. Due to the fact that the force of gravity on the surface of the Moon is 6 times less than on the surface of the Earth, it is much easier for gas molecules to leave the Moon. Therefore, our natural satellite is devoid of a noticeable atmosphere and hydrosphere.

The absence of an atmosphere and slow rotation around its axis (a day on the Moon is equal to an Earth month) lead to the fact that during the day the surface of the Moon heats up to 120 °C, and at night it cools down to -170 °C. Due to the lack of an atmosphere, the lunar surface is subject to constant “bombardment” of meteorites and smaller micrometeorites, which fall onto it at cosmic speeds (tens of kilometers per second). As a result, the entire Moon is covered with a layer of finely crushed material - regolith. As described by American astronauts who visited the Moon, and as photographs of lunar rovers’ footprints show, in its physical and mechanical properties (particle sizes, strength, etc.) regolith is similar to wet sand.

When large bodies fall onto the surface of the Moon, craters up to 200 km in diameter are formed. Craters with a meter and even centimeter diameter are clearly visible in panoramas of the lunar surface obtained from spacecraft.

Rock samples delivered by our Luna automatic stations and by American astronauts who visited the Moon on the Apollo spacecraft were studied in detail in laboratory conditions. This made it possible to obtain more complete information than when analyzing the rocks of Mars and Venus, which was carried out directly on the surface of these planets. Lunar rocks are similar in composition to terrestrial rocks such as basalts, norites and anorthosites. The set of minerals in lunar rocks is poorer than in terrestrial rocks, but richer than in meteorites. On our satellite there is not and never was either a hydrosphere or an atmosphere of the same composition as on Earth. Therefore, there are no minerals that can form in an aquatic environment and in the presence of free oxygen. Compared to terrestrial rocks, lunar rocks are depleted in volatile elements, but have a higher content of iron and aluminum oxides, and in some cases titanium, potassium, rare earth elements and phosphorus. No signs of life, even in the form of microorganisms or organic compounds, have been found on the Moon.

The light areas of the Moon - the "continents" and the darker ones - the "seas" differ not only in appearance, but also by topography, geological history and the chemical composition of the substance covering them. On the younger surface of the “seas”, covered with solidified lava, there are fewer craters than on the more ancient surface of the “continents”. In various parts of the Moon, relief forms such as cracks are noticeable, along which the crust shifts vertically and horizontally. In this case, only fault-type mountains are formed, and there are no folded mountains, so typical of our planet, on the Moon.

The absence of erosion and weathering processes on the Moon allows us to consider it a kind of geological reserve, where all the relief forms that arose during this time are preserved for millions and billions of years. Thus, studying the Moon makes it possible to understand geological processes events that took place on Earth in the distant past, of which there are no traces left on our planet.

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Introduction

1. General information about planet Earth

2. Earth as a planet in the solar system

3. The structure of planet Earth and its geosphere

Conclusion

Used Books

Introducedno

The earth is the cradle of humanity, but one cannot live in a cradle forever.

K.E. Tsiolkovsky

The topic of planet Earth, discussed in this work, is very relevant in our time, since each of us is an inhabitant of this planet, and influences its transformation or, conversely, change for the worse. Humanity and the environment are inextricably interconnected, and it depends on each of the parties how and in what direction one or the other will change.

Our planet is that part of the Universe on which civilizations arise, develop and die, and today the formation of a single modern society. Our future largely depends on how well humanity understands the structure of our planet. However, unfortunately, we have no more knowledge about the Earth than about distant stars A.P. Sadokhin KSE Chapter 5 “Earth as a subject of natural science” p.128 MOSCOW EKSMO 2007

The purpose of the work is to consider planet Earth as part of the solar system, to understand the structure of our planet and its geosphere.

Currently, the Earth is the object of study of many sciences - from geology and tectonics to philosophy and culture. In the aggregate of these sciences, there are branch sciences that study individual parts of the vertical and horizontal structure of the Earth (geology, climatology, soil science, etc.), as well as system sciences that synthesize the entire body of knowledge about the Earth to solve theoretical or applied problems (geography, Physiography, socio-economic geography, etc.). A.P.Sadokhin KSE Chapter 5 “Earth as a subject of natural science” p.128 MOSCOW EKSMO 2007

Tasks to be completed - what is the Earth, where and how is it located in the solar system, structure and geosphere.

Planet Earth represents an endless phenomenon for surprise, observation and scientific, practical, applied and theoretical interest, both from ordinary people and from scientists and scientists.

1. General information about planet Earth

Earth(from the common Slavic “zem” - floor, bottom), the third planet in order from the Sun in the solar system, astronomical sign or, +.

For a long time While the mythological picture of the world dominated, the Earth was considered a flat disk, standing on three elephants, whales or a turtle and covered on top with a semicircular vault of heaven. Only in the VI century. BC. One of the founders of ancient science, Pythagoras, expressed the idea that the Earth was spherical. Aristotle proved that the Earth is spherical in the 4th century. BC. Thus, the idea gradually became established that the Earth is a ball hanging motionless in the center of the Cosmos without any support, and around it the Moon, the Sun and the five then known planets revolve in ideal circular orbits. Fixed stars completed the established system in antiquity. Sadokhin A. KSE chapter 7.1 pp. 156-157

In 300 B.C. The geographer Eratosthenes quite accurately determined the size of the globe. He noticed that on the day of the summer solstice in the city of Siena, the Sun is at its zenith and illuminates the bottom of the deepest well. He then measured the angle of incidence of the sun's rays on the same day in Alexandria. Knowing the distance between cities, Eratosthenes calculated the circumference of the globe.

It would seem that the question of the shape of the Earth could be considered closed. But at the same time, the ancient doctrine of ideal bodies was refuted. Therefore, the question arose of how close the shape of the Earth is to a perfect sphere. TO end of XVII V. There are two points of view on this issue. To solve this question, it was necessary to measure pieces of meridian arcs at different latitudes and see how the distances per degree correlate. A.P. Sadokhin KSE chapter 7.1 page 158

Since then, the shape of the Earth has been refined several more times. It was only possible to determine it with great accuracy in the 20th century. using instruments installed on artificial Earth satellites. Today it is known for sure that the Earth is not a completely regular sphere. It is slightly compressed at the poles and somewhat elongated towards the North Pole. This figure is called the geoid . A.P. Sadokhin KSE chapter 7.1 page 158

EarthI- the third planet from the Sun. The fifth largest among all the planets in the solar system. It is also the largest in diameter, mass and density among the terrestrial planets. Sometimes referred to as World, Blue Planet, sometimes Terra (from the Latin Terra). The only body of the Solar System, in particular, and the Universe in general, known to man at the moment, inhabited by living organisms. http://ru.wikipedia.org/wiki/%C7%E5%EC%EB%FF

The earth has complex shape, determined by the combined action of gravity, centrifugal forces caused by the axial rotation of the Earth, as well as a combination of internal and external relief-forming forces. Approximately, the shape (figure) of the Earth is taken to be a level surface of gravitational potential (i.e., a surface at all points perpendicular to the direction of the plumb line), coinciding with the surface of water in the oceans (in the absence of waves, tides, currents and disturbances caused by changes in atmospheric pressure). This surface is called the geoid. The volume limited by this surface is considered the volume of the Earth. The average radius of the Earth is the radius of a sphere of the same volume as the volume of the geoid. To solve many scientific and practical problems of geodesy, cartography and others, the earth's ellipsoid is taken as the shape of the Earth. Knowledge of the parameters of the earth's ellipsoid, its position in the body of the earth. And also the gravitational field of the Earth is of great importance in astrodynamics, which studies the laws of motion of artificial cosmic bodies. These parameters are studied by ground-based astronomical-geodetic and gravimetric measurements and satellite geodesy methods.

Due to the rotation of the Earth, points at the equator have a speed of 465 m/sec, and points located at latitude have a speed of 465cos (m/sec), if we consider the Earth to be a sphere. The dependence of the linear speed of rotation, and, consequently, the centrifugal force on latitude leads to differences in the values of the acceleration of gravity at different latitudes.

At first glance, the Earth, as one of the planets in the solar system, is unremarkable. It is not the largest, but not the smallest of the planets. It is not closer than others to the sun, but it also does not live on the periphery of the planetary system. And yet the Earth has one unique feature- there is life on it. However, this is not noticeable when looking at the Earth from space. Clouds floating in the atmosphere are clearly visible. Yakusheva Alena chapter 1 page 2

Continents can be seen through the gaps in them. Most of the Earth is covered by oceans.

The appearance of life, living matter - the biosphere - on our planet was a consequence of its evolution. In turn, the biosphere had a significant impact on the entire further course of natural processes. So, if there was no life on Earth, chemical composition its atmosphere would be completely different.

Undoubtedly, a comprehensive study of the Earth is of enormous importance for humanity, but knowledge about it also serves as a kind of starting point for the study of the other planets of the terrestrial group.

Our planet differs from others not only in that it is “living”, but also in that it has many secrets. Secrets do exist. Science still cannot explain many phenomena, including objective reality which scientists themselves have no doubt about. For example, a place like Death Valley in California: it's all about the so-called moving stones. They can be seen at the bottom of the dried-up lake Racetrack Playa. Afonkin S.Yu. Mysteries of Planet Earth p. 28, 2010 Water appears in the lake only during the heavy rainy season, flowing down, it forms a strip and when it dries, a clay mosaic is formed, which is where the inexplicable appearance and movement of stones begins. No one has ever seen moving stones, but no one doubts their existence. Meanwhile, the mass of some boulders reaches 300-500 kg, and considerable force is required to move them. At first, scientists wanted to explain this as supernatural, but eventually came to the conclusion that they move only during strong hurricane winds, and the clay serves as a lubricant for them. There are still many inexplicable and unsolved things on our planet, so the Earth is one of them unique planets the entire solar system.

2. EarthI'm like a planet in the solar system

Planets are celestial bodies orbiting a star. They, unlike stars, do not emit light and heat, but shine with the reflected light of the star to which they belong. The shape of the planets is close to spherical. Currently, only the planets of the solar system are reliably known, but it is very likely that other stars also have planets.

According to modern cosmogonic concepts, the Earth was formed approximately 4.5 billion years ago by gravitational condensation from gas and dust matter scattered in the circumsolar space, containing all the chemical elements known in nature. The formation of the Earth was accompanied by differentiation of matter, which was facilitated by the gradual heating of the Earth's interior, mainly due to the heat released during the decay of radioactive elements (uranium, thorium, potassium, etc.). The result of this differentiation was the division of the Earth into concentrically located layers - geospheres, differing in chemical composition, state of aggregation and physical properties. The Earth's core formed in the center, surrounded by a mantle. From the lightest and most fusible components of the substance released from the mantle during melting processes, the earth's crust located above the mantle arose. The collection of these inner geospheres, bounded by the solid surface of the earth, is sometimes called the “solid” Earth (although this is not entirely accurate, since the outer part of the core is found to have the properties of a viscous fluid). The “solid” Earth contains almost the entire mass of the planet.

The physical characteristics of the Earth and its orbital motion have allowed life to persist over the past 3.5 billion years. According to various estimates, the Earth will maintain conditions for the existence of living organisms for another 0.5 - 2.3 billion years.

The Earth interacts (is pulled by gravitational forces) with other objects in space, including the Sun and Moon. The Earth revolves around the Sun and makes a complete revolution around it in approximately 365.26 solar days - a sidereal year. The Earth's rotation axis is inclined by 23.44° relative to the perpendicular to its orbital plane, this causes seasonal changes on the planet's surface with a period of one tropical year - 365.24 solar days. A day is now approximately 24 hours long. The Moon began its orbit around the Earth approximately 4.53 billion years ago. The Moon's gravitational effect on Earth causes ocean tides. The Moon also stabilizes the tilt of the Earth's axis and gradually slows down the Earth's rotation. Some theories suggest that asteroid impacts led to significant changes in the environment and the surface of the Earth, causing, in particular, mass extinctions of various species of living beings. http://ru.wikipedia.org/wiki/%C7%E5%EC%EB%FF

The Earth, like other planets in the Solar System, has early phases of evolution: the accretion phase (birth), the melting of the outer sphere of the globe and the primordial crust phase (lunar phase). A.P. Sadokhin KSE chapter 5 p. 131 The difference between our planet and others is that almost all the planets did not experience the lunar phase, and if there was one, it either did not end or passed to no avail, because Only on Earth did bodies of water (oceans) appear in which a combination of substances could occur for the future development of the planet.

3. The structure of planet Earthand its geosphere

The Earth, like other terrestrial planets, has a layered internal structure. It consists of hard silicate shells (crust, extremely viscous mantle), and a metallic core. The outer part of the core is liquid (much less viscous than the mantle), and the inner part is solid.

The Earth's interior is divided into layers according to chemical and physical (rheological) properties, but unlike other terrestrial planets, internal structure The Earth has a distinct outer and inner core??. The outer layer of the Earth is a hard shell consisting mainly of silicates. It is separated from the mantle by a boundary with a sharp increase in the velocities of longitudinal seismic waves - the Mohorovicic surface. Hard bark and viscous top part the mantle makes up the lithosphere. Beneath the lithosphere is the asthenosphere, a layer of relatively low viscosity, hardness and strength in the upper mantlehttp://ru.wikipedia.org/wiki/%C7%E5%EC%EB%FF - cite_note-95.

Significant changes in the crystalline structure of the mantle occur at a depth of 410-660 km below the surface, covering the transition zone that separates the upper and lower mantle.

Internal heat:

The planet's internal heat is provided by a combination of residual heat left over from the accretion of matter that occurred during the early stages of Earth's formation (about 20%) and the radioactive decay of unstable isotopes: potassium-40, uranium-238, uranium-235 and thorium-232. All three isotopes have half-lives of more than a billion years. At the planet's center, temperatures may rise to 6,000 °C (10,830 °F) (more than the surface of the Sun), and pressures may reach 360 GPa (3.6 million atm). Part of the thermal energy of the core is transferred to the earth's crust through plumes. Plumes lead to the appearance of hot spots and traps. Since most of the heat produced by the Earth is provided by radioactive decay, at the beginning of the Earth’s history, when the reserves of short-lived isotopes had not yet been depleted, the energy release of our planet was much greater than now. Voitkevich V. G. Structure and composition of the Earth // Origin and chemical evolution of the Earth / ed. L. I. Prikhodko. - M.: Nauka, 1973. - P. 57-62. -- 168 p. The average loss of thermal energy of the Earth is 87 mW m?2 or 4.42 H 10 13 W (global heat loss). (August 1993) “Heat flow from the Earth's interior: Analysis of the global data set.” Reviews of Geophysics 31 (3): 267-280. earth solar planet magnetism

Geospheres - geographically concentric shells ( continuous or discontinuous) that make up planet Earth. Thus, we can distinguish a number of geospheres that make up the Earth:

- core,

- mantle,

- lithosphere,

- hydrosphere,

- atmosphere,

- magnetosphere. A.P. Sadokhin KSE chapter 5 page 151 MOSCOW EKSMO 2007

Geospheres are conventionally divided into basic (main) as well as relatively autonomously developing secondary geospheres: anthroposphere (Rodoman B.B. 1979), sociosphere (Efremov Yu.K. 1961), noosphere (Vernadsky V.I.).

Lithosphere :

Lithosphere (from other Greek . lYaipt -- stone and UTSB ? Sat -- ball, sphere) -- solid shell of the Earth. Comprises earth's crust and top mantle. In the structure of the lithosphere, mobile regions (folded belts) and relatively stable platforms are distinguished. Lithosphere blocks -- lithospheric plates -- move along relatively plastic asthenosphere. The section of geology is devoted to the study and description of these movements. plate tectonics. Below the lithosphere is located the asthenosphere, which makes up the outer part of the mantle. The asthenosphere behaves like a superheated and extremely viscous liquid, where the speed of seismic waves decreases, indicating a change in the plasticity of the rocks. Lithosphere - article from the Great Soviet Encyclopedia. 1981 To indicate external shells of the lithosphere were used, at the moment, obsolete term sial , derived from the name of the basic elements rocks Si (lat. Silicium -- silicon) and Al (lat. Aluminum -- aluminum).

The lower boundary of the lithosphere is unclear and is determined by a sharp decrease in rock viscosity, changes in the speed of propagation of seismic waves and an increase in electrical conductivity. The thickness of the lithosphere on continents and under the ocean varies, and is respectively: 25-200 km. and 5-100 km.

The main part of the lithosphere consists of igneous igneous rocks (95%), among which granites and granitoids predominate on the continents, and basalts in the oceans.

The deep strata of the lithosphere, which are studied by geophysical methods, have a rather complex, insufficiently studied structure, just like the mantle and core of the Earth.

Modern soils are a three-phase system (different-grained solid particles, water and gases dissolved in the air), which consists of a mixture of mineral particles and organic substances. Soils play a huge role in the circulation of water, substances and carbon dioxide. http:// ecos.org.ua/?p=120

Earth's crust:

The Earth's crust is the upper part of the solid Earth. It is separated from the mantle by a boundary with a sharp increase in seismic wave velocities - the Mohorovicic boundary. There are two types of crust - continental and oceanic. The thickness of the crust ranges from 6 km under the ocean to 30-70 km on the continents. In the structure of the continental crust, three geological layers are distinguished: sedimentary cover, granite and basalt. The oceanic crust is composed predominantly of basic rocks, plus sedimentary cover. The earth's crust is divided into lithospheric plates of different sizes, moving relative to each other. The kinematics of these movements is described by plate tectonics. The Earth's crust beneath the oceans and continents differs significantly.

The earth's crust under the continents usually has a thickness of 35-45 km; in mountainous areas the thickness of the crust can reach up to 70 km. With depth in the composition of the earth's crust, the content of magnesium and iron oxides increases, the content of silica decreases, and this trend occurs to a greater extent during the transition to the upper mantle (substrate). Earth's crust - article from the Great Soviet Encyclopedia. 1981. The upper part of the continental crust is a discontinuous layer consisting of sedimentary and volcanic rocks. Layers can be crumpled into folds or displaced along the gap. There is no sedimentary shell on the shields. Below, there is a granite layer consisting of gneisses and granites (speed longitudinal waves in this layer - up to 6.4 km/sec). Even lower is the basalt layer (6.4-7.6 km/sec), composed of metamorphic rocks, basalts and gabbro. Between these 2 layers there is a conventional boundary called the Conrad surface. The speed of longitudinal seismic waves when passing through this surface increases abruptly from 6 to 6.5 km/. Conrad's surface - article from the Great Soviet Encyclopedia 1981.

The crust under the oceans is 5-10 km thick. It is divided into several layers. First there is the top layer, consisting of bottom sediments, less thick. Below lies the second layer, composed mainly of serpentinite, basalt and, probably, interbeds. The speed of longitudinal seismic waves in this layer reaches 4-6 km/s, and its thickness is 1-2.5. The lower, “oceanic” layer is composed of gabbro. This layer has an average thickness of about 5 km and a speed of seismic waves of 6.4-7 km/s. Earth's crust - article from the Great Soviet Encyclopedia 1981.

General structure of planet Earth. (1979) “Structural geology of the Earth's interior.” Proceedings National Academy of Science 76 (9): 4192-4200.

Depth, km		Density, g/cm 3
	Lithosphere (in places varies from 5-200 km)
	Kora (varies from 5-70 km in places)
	The uppermost part of the mantle

	Asthenosphere
	Outer core
	Inner core

Asthenosphere-- (from other Greek ?uienYut “powerless” and utsb?sb “ball”) the upper plastic layer of the planet’s upper mantle (example: the Earth’s asthenosphere), also called the Guttenberg layer. The asthenosphere is distinguished by a decrease in the velocities of seismic waves. Above the asthenosphere lies the lithosphere - the solid shell of the planet. On Earth, the roof of the asthenosphere lies at depths of 80-100 km (under continents) and 50-70 km (sometimes less) (under oceans). The lower boundary of the earth's asthenosphere is at a depth of 250-300 km, blurred. It is distinguished according to geophysical data as a layer of reduced velocity of transverse seismic waves and increased electrical conductivity. http://ru.wikipedia.org/wiki/Asthenosphere

The water shell of the Earth is represented on our planet by the World Ocean, fresh waters of rivers and lakes, glacial and underground waters. The total water reserves on Earth are 1.5 billion km 3 . Of this amount of water, 97% is salty sea water, 2% is frozen glacial water and 1% is fresh water. A.P. Sadokhin chapter 5 page 140 MOSCOW EKSMO 2007

Hydrosphere - this is the continuous shell of the Earth, since the seas and oceans turn into The groundwater on land, and between land and sea there is a constant water cycle, the annual volume of which is 100 thousand km 3. About 10% of evaporated water is carried to land, falls on it, and then is either carried away by rivers into the ocean, or goes underground, or is preserved in glaciers. The water cycle in nature is not a completely closed cycle. Today it has been proven that our planet is constantly losing some of the water and air that go into outer space. Therefore, over time, the problem of conserving water on our planet arises. A.P. Sadokhin chapter 5 p. 141 MOSCOW EKSMO 2007

Mantle is the silicate shell of the Earth, located between the earth's crust and the Earth's core.

The mantle makes up 67% of the Earth's mass and about 83% of its volume (excluding the atmosphere). It extends from the boundary with the earth's crust (at a depth of 5-70 kilometers) to the boundary with the core at a depth of about 2900 km. It is separated from the earth's crust by the Mohorovicic surface, where the speed of seismic waves during the transition from the crust to the mantle quickly increases from 6.7-7.6 to 7.9-8.2 km/s. The mantle occupies a huge range of depths, and with increasing pressure in the substance, phase transitions occur, during which minerals acquire an increasingly dense structure. The Earth's mantle is divided into an upper mantle and a lower mantle. Upper layer, in turn, is divided into the substrate, the Gutenberg layer and the Golitsyn layer (middle mantle). The Earth's mantle - article from the Great Soviet Encyclopedia 1981.

According to modern scientific ideas, the composition of the earth's mantle is considered to be similar to the composition of stony meteorites, in particular chondrites. Data on the chemical composition of the mantle were obtained based on analyzes of the deepest igneous rocks that entered the upper horizons as a result of powerful tectonic uplifts with the removal of mantle material. Material from the upper part of the mantle was collected from the bottom of different parts of the ocean. The density and chemical composition of the mantle differ sharply from the corresponding characteristics of the core. The mantle is formed by various silicates (silicon-based compounds), primarily the mineral olivine. The composition of the mantle mainly includes chemical elements that were in a solid state or in solid chemical compounds during the formation of the Earth: silicon, iron, oxygen, magnesium, etc. These elements form silicates with silicon dioxide. In the upper mantle (substrate), most likely, there is more forsterite MgSiO 4; deeper, the content of fayalite Fe 2 SiO 4 increases somewhat. In the lower mantle, under the influence of very high pressure, these minerals decomposed into oxides (SiO 2, MgO, FeO). Earth - article from the Great Soviet Encyclopedia 1981

The aggregate state of the mantle is determined by the influence of temperatures and ultra-high pressure. Due to pressure, the substance of almost the entire mantle is in a solid crystalline state, despite the high temperature. The only exception is the asthenosphere, where the effect of pressure is weaker than temperatures close to the melting point of the substance. Because of this effect, it appears that the substance here is either in amorphous state, or semi-molten.

Core - the central, deepest part of the Earth, the geosphere, located under the mantle and, presumably, consisting of an iron-nickel alloy with an admixture of other siderophile elements (a group of transitional chemical elements belonging mainly to group VIII periodic table Mendeleev). Depth of occurrence - 2900 km. Average radius of the sphere = 3485 km. The core is divided into a solid inner core with a radius of 1300 km. and a liquid outer core with a radius of 2200 km, between which a transition zone is sometimes distinguished. The temperature in the center of the Earth's core reaches 600 0 C. The Earth's Center is 1000 Degrees Hotter than Previously Thought. European Synchrotron Radiation Facility (April 26, 2013), density - 12.5 t/m 3, pressure up to 360 GPa (3, 55 million atmospheres). Core mass = 1.9354*10 24 kg.

The liquid state of the outer core is associated with ideas about the nature of the earth's magnetism. The Earth's magnetic field is variable, the position changes from year to year magnetic poles. Paleomagnetic studies have shown that, for example, over the past 80 million years there has been not only a change in field strength, but also multiple systematic magnetization reversal, as a result of which the North and South magnetic poles of the Earth changed places. It is assumed that the magnetic field is created by a process called the self-excited dynamo effect. The role of the rotor (moving element) of the dynamo can be played by the mass of the liquid core, moving as the Earth rotates around its axis, and the excitation system is formed by currents that create closed loops inside the sphere of the core. A.P.Sadokhin KSE chapter 5 p.152 MOSCOW EKSMO 2007

Chemical composition of the nucleus

Source
Allegre et al., 1995 p.522	79,39 + 2	4, 87 + 0,3	2,30 + 0,2	4,10 + 0,5
Mc Donough, 2003 p.556

An important component of our planet and others is the atmosphere, since we are in this environment always and everywhere, but if it were not for the important chemical elements (oxygen, nitrogen, hydrogen, etc.) and their proportional combination, then all living beings could not exist.

Atmosphere- (ancient Greek “atmo” - steam and “sphere” - ball) - the gas shell (geosphere) surrounding planet Earth. Its inner surface covers the hydrosphere and partly the earth's crust, while its outer surface borders the near-Earth part of outer space.

The set of branches of physics and chemistry that study the atmosphere is usually called atmospheric physics. The atmosphere determines the weather on the Earth's surface, meteorology studies weather, and climatology deals with long-term climate variations. http://ru.wikipedia.org/wiki/%C0%F2%EC%EE%F1%F4%E5%F0%E0_%C7%E5%EC%EB%E8

The lower layers of the atmosphere consist of a mixture of gases: nitrogen, oxygen, carbon dioxide, argon, neon, helium, krypton, hydrogen, xenon http://www.grandars.ru/shkola/geografiya/sostav-atmosfery.html, as well as in the form Small impurities in the air contain the following gases: ozone, methane, substances such as carbon monoxide (CO), nitrogen and sulfur oxides, ammonia. In the high layers of the atmosphere, the composition of the air changes under the influence of hard radiation from the Sun, which leads to the disintegration of oxygen molecules into atoms. Atomic oxygen is the main component of the high layers of the atmosphere. Finally, in the layers of the atmosphere furthest from the Earth's surface, the main components are the lightest gases - hydrogen and helium. Since the bulk of the substance is concentrated in the lower 30 km, changes in the composition of the air at altitudes above 100 km do not have a noticeable effect on the overall composition of the atmosphere. Collier's Encyclopedia - atmosphere.

Also, such a sphere as the magnetosphere plays an important role.

Magnetosphere - is a complex physical object formed as a result of the interaction of its own magnetic field Earth, interplanetary magnetic field and supersonic solar wind flow. In addition, inside the magnetosphere there are streams of charged particles, which in turn generate magnetic fields.

The Earth's own magnetic field (field from internal sources) can be described using a spherical harmonic expansion, the expansion coefficients being determined from ground-based measurements. The geomagnetic field gradually decreases over time, and the coordinates of the magnetic poles slowly change. Currently, the IGRF (International Geomagnetic Reference Field) model is generally accepted, which allows one to calculate the geomagnetic field for a given epoch in the interval 1945-2010. To the roughest approximation, the geomagnetic field can be considered as a dipole field with a magnetic moment of the order of 8 10 19 G m 3. The center of the dipole is displaced relative to the center of the Earth by ~ 400 km, and the axis is tilted so that it intersects the Earth's surface at coordinates 75° N, 101° W. and 66° S, 141° E. The contribution from multipole terms decreases rapidly with increasing distance from the Earth. Penetration of cosmic rays into the Earth's magnetosphere. Yushkov B.Yu. Introduction.

From the above we can conclude that each of these spheres is unique and important for US: people, animals, amphibians, etc. The composition and chemical properties of these spheres on our planet differ in many respects from the composition of other planets of the solar system, thereby allowing life and develop living beings and organisms.

Conclusion

In this work we examined the following topic: Earth as a planet of the solar system: its structure and geosphere.

We learned that Earth is the fifth largest planet in size and mass, but it is the largest of the terrestrial planets, which includes Mercury, Venus, Earth, and Mars. The most important difference between the Earth and the other planets of the solar system is the existence of life on it, which reached its highest, intelligent form with the advent of man. Most of the Earth's surface is occupied by the World Ocean (361.1 million km 2, or 70.8%), land is 149.1 million km 2 (29.2%) and forms six large massifs - continents: Eurasia, Africa , North America, South America, Antarctica and Australia.

The mass of the Earth is 5976*1021 kg, which is 1/448 of the mass of the major planets and 1/330,000 of the mass of the Sun. Under the influence of the Sun's gravity, the Earth, like other bodies in the Solar System, revolves around it in an elliptical (not much different from a circular) orbit. The Sun is located at one of the foci of the Earth's elliptical orbit, as a result of which the distance between the Earth and the Sun varies throughout the year from 147.117 million km (at perihelion) to 152.083 million km (at aphelion). The period of revolution of the Earth around the Sun, called a year, has a slightly different value depending on in relation to which bodies or points of the celestial sphere the Earth’s movement and the associated apparent movement of the Sun across the sky are considered.

Our planet Earth has a layered internal structure. It consists of hard silicate shells (crust, extremely viscous mantle), and a metallic core. It consists of a number of geospheres: core, mantle, lithosphere, hydrosphere, magnetosphere, atmosphere. Each of them has its own properties, which together form an area for the life of living beings.

Much has changed on our planet over the past millennia, some for the better, some (to our shame) not for the better. better side, but one way or another this is our planet and we must know it, protect it, love it.

WITHlist of literature

1 - Sadokhin A.P. KSE Moscow EXMO 2007

2 - Afonkin S.Yu. Mysteries of planet Earth. 2010

3 - Naydysh V.M KSE 2004

4 - Voitkevich V.G. Structure and composition of the Earth. 1973

5 - Great Soviet Encyclopedia 1981

6 - Collier's Encyclopedia.

7 - Yushkov B.Yu. Penetration of cosmic rays into the Earth's magnetosphere.

Internet resources:

1 - http://ru.wikipedia.org

2 - http://www.grndars.ru

3 - http://ecos.org.ua/?p=120

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