We all live on the beautiful planet Earth, about which humanity has already learned a lot, but even more is still hidden from us and is waiting in the wings until man’s desire for knowledge reveals all the secrets of our world.

General information about planet Earth

Let's remember what we know about planet Earth. Earth is the only inhabited planet in our solar system, even moreover, the only one on which there is life. Earth is the third planet, counting from the Sun, before Earth there are two more planets Mercury and Venus. The Earth rotates around the Sun and the inclination of the rotation axis relative to the Sun is 23.439281°, thanks to this inclination we can observe the change of seasons throughout the year. The distance from the earth to the sun is 149,600,000 km; for a stream of light to cover the distance from the sun to the earth it needs 500 seconds or 8 minutes. Our planet also has a satellite, the Moon, which revolves around the Earth, just as the Earth revolves around the sun. The distance from the Earth to the Moon is 384,400 km. The speed of the Earth's movement in its orbit is 29.76 km/sec. The Earth makes a complete rotation on its axis in 23 hours 56 minutes and 4.09 seconds. For convenience, it is generally accepted that there are 24 hours in a day, but to compensate for the remaining time, another day is added to the calendar every 4 years and this year is called a leap year. A day is added in the month of February, which usually has 28 days; a leap year has 29 days. There are 365 days in a year and 366 days in a leap year, this is a complete cycle of changing seasons (winter, spring, summer, autumn).

Earthly dimensions and parameters

Now let's move from space to planet Earth itself. In order for life to arise on the planet, there must be many factors and conditions that create a favorable habitat for countless living organisms inhabiting the Earth. In fact, the more we learn about our common home, the more clearly we understand how complex and perfect an organism the planet Earth is. There is nothing superfluous, everything has its place, and everyone has their own important role to play.

The structure of planet Earth

There are a total of 8 planets in our solar system, 4 of which belong to the terrestrial planets and 4 to the gas group. Planet Earth is the largest terrestrial planet and has the greatest mass, density, magnetic field and gravity. The structure of the Earth is not homogeneous, and it can be conditionally divided into layers (levels): the earth's crust; mantle; core.
Earth's crust – the uppermost layer of the Earth’s solid shell, it in turn is divided into three layers: 1) sedimentary layer; 2)granite layer; 3) basalt layer.
The thickness of the earth's crust can range from 5 - 75 km deep into the Earth. This range depends on the location of measurements, for example, on the ocean floor the thickness is minimal, and on continents and mountain ranges it is maximum. As we have already said, the earth's crust is divided into three parts, the basalt layer was formed first, therefore it is the lowest, followed by the granite layer, which is absent on the ocean floor, and the uppermost sedimentary layer. The sedimentary layer is constantly being formed and modified, and humans play an important role in this.
Mantle - the layer next after the earth’s crust, which is the most voluminous, about 83% of the total volume of the Earth and approximately 67% of its mass, the thickness of the mantle reaches 2900 km. The upper layer of the mantle, which is 900 km, is called magma. Magma is molten minerals, and the output of liquid magma is called lava.
Core - This is the center of planet Earth, consists mainly of iron and nickel. The radius of the earth's core is approximately 3500 km. The core is also divided into an outer core with a thickness of 2200 km, which has a liquid structure and an inner core with a radius of about 1300 km. The temperature in the center of the core is close to 10,000 °C; on the surface of the core, the temperature is significantly lower than 6,000 °C.

Shape of the Earth. Diameter of the Earth. Earth's mass. Age of the Earth.

If you ask the question, “What is the shape of the Earth?”, we will hear possible answers: round, sphere, ellipsoid, but this is not entirely true; a special term Geoid was introduced to denote the shape of the Earth. A geoid is essentially an ellipsoid of revolution. Determining the shape of the planet made it possible to accurately determine the diameters of planet Earth. Yes, it is precisely the diameters of the Earth that, due to its irregular shape, are distinguished by several:
1) the average diameter of the Earth is 12,742 km;
2) the equatorial diameter of the Earth is 12756.2 km;
3) the polar diameter of the Earth is 12713.6 km.

The circumference along the equator is 40,075.017 km, and along the meridian it is slightly less than 40,007.86 km.
The mass of the Earth is a rather relative quantity that is constantly changing. The mass of the earth is 5.97219 × 10 24 kg. The mass increases due to the settling of cosmic dust on the surface of the planet, the fall of meteorites, etc., due to which the mass of the Earth increases annually by approximately 40,000 tons. But due to the dispersion of gases into outer space, the mass of the Earth decreases by about 100,000 tons per year. Also, the loss of Earth's mass is affected by an increase in temperature on the planet, which contributes to more intense thermal movement and the leakage of gases into space. The smaller the Earth's mass becomes, the weaker its gravity and the more difficult it becomes to maintain an atmosphere around the planet.
Thanks to the radioisotope dating method, scientists were able to establish the age of the Earth; it is 4.54 billion years. The age of the Earth was more or less accurately determined back in 1956, and was subsequently slightly adjusted with the development of technology and measurement methods.

Other information about planet Earth

The Earth's surface area is 510,072,000 km², of which water spaces occupy 361,132,000 km², which is 70.8% of the Earth's surface. The land area is 148,940,000 km², which is 29.2% of the Earth's surface area. Due to the fact that water covers much more of the surface of the planet, it was more logical to name our planet Water.
The volume of the Earth is 10.8321 x 10 11 km³.
The highest point on the earth's surface above sea level is Mount Everest, whose height is 8848 m, and the deepest place in the world's oceans is considered to be the Mariana Trench, its depth is 11022 m. Well, if we give average values, then the average height of the Earth's surface above sea level is 875 m , and the average depth of the ocean is 3800 m.
The acceleration of gravity, also known as the acceleration of gravity, will be slightly different in different parts of the planet. At the equator g=9.780 m/s² and gradually increases, reaching g=9.832 m/s² at the poles. The average value of the acceleration due to gravity is taken to be g = 9.80665 m/s²
Composition of the atmosphere of planet Earth: 1) 78.08% nitrogen (N2); 2) 20.95% oxygen (O2); 3) 0.93% argon (Ar); 0.039% - carbon dioxide (CO2); 4) 1% water vapor. Other elements from Mendeleev's periodic table are also present in small quantities.
Planet Earth is so large and interesting that, despite how much we already know about the Earth, it never ceases to amaze us with the secrets and unknowns that we continue to encounter.

> Planet Earth

Everything about the planet Earth for children: how it appeared and was formed, interesting facts, what the structure is made of in photos and drawings, the rotation of the Earth, the Moon and life.

Start a story about Earth for the little ones It’s possible because we live on the third planet from the Sun. Parents or teachers At school should be explain to the children that they were very lucky. After all, the Earth is so far the only known planet in the solar system that contains an atmosphere with oxygen, liquid oceans on the surface and life.

If we consider by size, then we occupy fifth place (less than , and , but greater than and ).

The diameter of planet Earth is 13,000 km. It is circular in shape because gravity pulls in matter. Although this is not a perfect circle, because rotation causes the planet to compress at the poles and expand at the equator.

Water occupies approximately 71% (most of it is oceans). 1/5 of the atmosphere consists of oxygen, which is produced by plants. While scientists have been studying the planet for centuries, spacecraft have made it possible to look at it from space. Below, schoolchildren and children of all ages will be able to consider interesting facts about the Earth and receive a full description of the third planet from the Sun with photos and pictures. But it should be recalled that the Earth has a class, or rather a planetary type - a rocky body (there are also ice and gas giants that differ in characteristics).

Characteristics of the Earth's orbit - explanation for children

To give full explanation for children, parents must reveal the concept of an axis. This is an imaginary line running through the center from the North to the South Pole. It takes 23.934 hours to complete one revolution, and 365.26 days (Earth year) to orbit around the Sun.

Children should know that the earth's axis is tilted relative to the plane of the ecliptic (the imaginary surface of the earth's orbit around the sun). Because of this, the northern and southern hemispheres sometimes rotate and face away from the Sun. This leads to a change in seasons (the amount of light and heat received changes).

The Earth's orbit is not a perfect circle, but an oval ellipse (this is common to all planets). It approaches the Sun in early January and moves away in July (although this has less effect on heating and cooling than the tilt of the Earth's axis). Should explain to the children the value of having a planet in the habitable zone. This is the distance that allows the temperature to maintain water in a liquid state.

Earth's orbit and rotation - explanation for children

• Average distance from the Sun: 149,598,262 km.
• Perihelion (closest distance to the Sun): 147,098,291 km.
• Aphelion (farthest distance from the Sun): 152,098,233 km.
• Duration of a solar day (one axial revolution): 23.934 hours.
• Length of year (one round the Sun): 365.26 days.
• Equatorial inclination to orbit: 23.4393 degrees.

Formation and evolution of the Earth - explanation for children

Explanation for children will remain incomplete if description of the Earth will bypass the background. Researchers believe that the Earth formed along with the Sun and other planets 4.6 billion years ago. Then it reunited with a huge cloud of gas and dust - the solar nebula. Gravity gradually destroyed it, giving it more speed and a disk shape. Most of the material was drawn to the center and began to form.

Other particles collided and combined to form larger bodies. The solar wind was so powerful that it managed to dislodge lighter elements (hydrogen and helium) from the most distant worlds. This is why the Earth and other planets became rocky.

In early history, planet Earth may seem like a lifeless piece of rock to children. Radioactive materials and pressure rising from the depths provided enough heat to melt the interior. This caused some chemicals to splash out to form water, while others became atmospheric gases. According to recent data, the crust and oceans could have appeared 200 million years after the formation of the planet.

Children should know that earthly history is divided into 4 eons: Hadean, Archean, Proterozoic and Phanerozoic. The first three took almost 4 billion years and are collectively called the Precambrian. Evidence of life was discovered in the Archean about 3.8 billion years ago. But life was not rich until the Phanerozoic.

The Phanerozoic period is divided into 3 eras: Paleozoic, Mesozoic and Cenozoic. The first demonstrated the emergence of many varieties of animals and plants in the seas and on land. The Mesozoic provided dinosaurs, but the Cenozoic is literally our era (mammals).

Most fossils from the Paleozoic are invertebrate animals (corals, trilobites and mollusks). Fish fossils have been dated back to 450 million years ago, and amphibians to 380 million years old. Vast forests, swamps and early reptiles inhabited the Earth 300 million years ago.

The Mesozoic was the period in which dinosaurs lived. Although mammal fossils were also 200 million years old. During this period, flowering plants seized power (and continue to do so today).

The Cenozoic era began about 65 million years ago, when the dinosaurs became extinct (scientists attribute this to cosmic influences). Mammals managed to survive, and they became the main creatures on the planet.

Composition and structure of the Earth - explanation for children

Atmosphere

Composition: 78% nitrogen and 21% oxygen with small admixtures of water, carbon dioxide, argon and other gases. Nowhere else in the solar system will you find an atmosphere filled with free oxygen. But this is exactly what turned out to be important for our lives.

The earth is surrounded by air, becoming thin as it moves away from the surface. At an altitude of 160 km, it is so thin that satellites have to overcome only minor resistance. But traces of the atmosphere are still found at an altitude of 600 km.

The lowest layer of the atmosphere is the troposphere. She does not stop moving and is responsible for weather conditions. Sunlight heats the atmosphere, creating a warm air current. It expands and cools as pressure decreases. Children must understand that cold air becomes denser, so it sinks down to warm the lower layers.

The stratosphere is located at an altitude of 48 km. This is a stationary ozone layer created by ultraviolet light causing a trio of oxygen atoms to form the ozone molecule. For the little ones It will be interesting to know that it is ozone that protects us from most of the dangerous ultraviolet radiation.

Carbon dioxide, water vapor and other gases trap heat and warm the Earth. If it were not for this “greenhouse effect,” the surface would be too cold and would not allow life to develop. Although the wrong greenhouse could turn us into a hellishly hot version of Venus.

Satellites in Earth orbit have shown that the upper atmosphere expands during the day and contracts at night due to heating and cooling processes.

A magnetic field

The Earth's magnetic field is created by currents emanating from the outer layer of the earth's core. Magnetic poles are always moving. The magnetic north pole accelerates movement up to 40 km per year. In a few decades, it will leave North America and reach Siberia.

NASA believes the magnetic field changes in other directions as well. Globally it has weakened by 10%, measured since the 19th century. Although these transformations are insignificant if you delve into the distant past. Sometimes the field completely flipped, reversing the north and south poles.

When particles charged by the Sun find themselves in a magnetic field, they break up into air molecules above the poles and create the northern and southern lights.

Chemical composition

The most common element in the earth's crust is oxygen (47%). Next come silicon (27%), aluminum (8%), iron (5%), calcium (4%), and 2% each of potassium, sodium and magnesium.

The Earth's core consists mainly of nickel, iron and lighter elements (sulfur and oxygen). The mantle is made of silicate rocks rich in iron and magnesium (a combination of silicon and oxygen called silica, and materials containing it are called silicate).

Internal structure

Schoolchildren and children of all ages should remember that the Earth's core is 7,100 km wide (a little more than half the Earth's diameter and roughly the size of Mars). The outermost layers (2250 km) are liquid, but the inner one is a solid body and reaches 4/5 the size of the Moon (2600 km in diameter).

Above the core is a mantle 2900 km thick. Children could hear At school that it is not completely rigid, but can flow very slowly. The Earth's crust floats across it, causing the continents to shift almost imperceptibly. True, people realize this in the form of earthquakes, erupting volcanoes and the formation of mountain ranges.

There are two types of earth's crust. The landmass of the continents consists mostly of granite and other light silicate minerals. The ocean floors are dark and dense volcanic rock - basalt. The continental crust is up to 40 km thick, although it may vary depending on the specific area. The oceanic one grows to only 8 km. Water fills low areas of basalt and forms the world's oceans. The Earth has a lot of water, so it completely fills the ocean basins. The rest reaches the edges of the continents - the continental plume.

The closer to the core, the warmer it is. At the very bottom of the continental crust, temperatures reach 1000 °C and increase by 1 °C with every kilometer down. Geologists suggest that the outer core is heated to 3700-4300 °C, and the inner core - 7000 °C. This is even hotter than the surface of the Sun. Only enormous pressure allows its structure to be preserved.

Recent exoplanet studies (such as NASA's Kepler mission) suggest that Earth-like planets are found throughout our galaxy. Almost a quarter of observed solar stars may have potential habitable Earths.

Earth's Moon - explanation for children

Children should not forget that the Earth has a faithful satellite - the Moon. It reaches a width of 3474 km (about a quarter of the Earth's diameter). Our planet has only one satellite, although Venus and Mercury do not have them at all, and some have two or more.

The moon was formed after a giant object crashed into the Earth. The torn off fragments became the constituent material of the Moon. Scientists believe the object was roughly the size of Mars.

It is currently known that Earth is the only planet in the Universe inhabited by life. There are several million known species from the deepest ocean floor to the highest levels of the atmosphere. But researchers say not everything has been discovered yet (estimated at 5-100 million, of which only about 2 million have been found).

Scientists suspect that there are other habitable planets. Among them, Saturn's moon Titan or Jupiter's Europa are being considered. While researchers are still understanding the processes of evolution, it seems that Mars has every chance of having organisms. Some people think that it was from Martian meteorites that fell to Earth that our life originated.

It is important to remind children that our planet is considered the most studied, because the exploration of the Earth has been carried out from primitive tribes to today. Many interesting sciences offer characteristics of the planet from all sides. Geography of the Earth reveals countries, geology studies the composition and movement of plates, and biology examines living organisms. To make it more interesting for your child to explore the Earth, use printed or Google maps, as well as our online telescopes. Do not forget that planet Earth is a unique system and so far the only world with life. Therefore, it must not only be studied comprehensively, but also protected.

Earth is the third planet from the Sun and the largest of the terrestrial planets. However, it is only the fifth largest planet in terms of size and mass in the Solar System, but surprisingly, it is the densest of all the planets in the system (5.513 kg/m3). It is also noteworthy that Earth is the only planet in the solar system that people themselves have not named after a mythological creature - its name comes from the old English word "ertha", which means soil.

It is believed that the Earth was formed somewhere around 4.5 billion years ago, and is currently the only known planet where the existence of life is possible in principle, and the conditions are such that life is literally teeming on the planet.

Throughout human history, people have sought to understand their home planet. However, the learning curve turned out to be very, very difficult, with many mistakes made along the way. For example, even before the existence of the ancient Romans, the world was understood as flat, not spherical. A second clear example is the belief that the Sun revolves around the Earth. It was only in the sixteenth century, thanks to the work of Copernicus, that people learned that the Earth was actually just a planet orbiting the Sun.

Perhaps the most important discovery about our planet over the past two centuries is that the Earth is both a common and unique place in the solar system. On the one hand, many of its characteristics are rather ordinary. Take, for example, the size of the planet, its internal and geological processes: its internal structure is almost identical to the three other terrestrial planets in the solar system. On Earth, almost the same geological processes occur that form the surface, which are characteristic of similar planets and many planetary satellites. However, with all this, the Earth simply has a huge number of absolutely unique characteristics that strikingly distinguish it from almost all currently known terrestrial planets.

One of the necessary conditions for the existence of life on Earth is without a doubt its atmosphere. It consists of approximately 78% nitrogen (N2), 21% oxygen (O2) and 1% argon. It also contains very small amounts of carbon dioxide (CO2) and other gases. It is noteworthy that nitrogen and oxygen are necessary for the creation of deoxyribonucleic acid (DNA) and the production of biological energy, without which life cannot exist. In addition, oxygen present in the ozone layer of the atmosphere protects the planet's surface and absorbs harmful solar radiation.

What's interesting is that a significant amount of the oxygen present in the atmosphere is created on Earth. It is formed as a byproduct of photosynthesis, when plants convert carbon dioxide from the atmosphere into oxygen. Essentially, this means that without plants, the amount of carbon dioxide in the atmosphere would be much higher and oxygen levels much lower. On the one hand, if carbon dioxide levels rise, it is likely that the Earth will suffer from a greenhouse effect like this. On the other hand, if the percentage of carbon dioxide became even slightly lower, then the reduction in the greenhouse effect would lead to a sharp cooling. Thus, current carbon dioxide levels contribute to an ideal comfortable temperature range of -88°C to 58°C.

When observing the Earth from space, the first thing that catches your eye is oceans of liquid water. In terms of surface area, oceans cover approximately 70% of the Earth, which is one of the most unique properties of our planet.

Like the Earth's atmosphere, the presence of liquid water is a necessary criterion for supporting life. Scientists believe that life on Earth first appeared 3.8 billion years ago in the ocean, and the ability to move on land appeared in living creatures much later.

Planetologists explain the presence of oceans on Earth for two reasons. The first of these is the Earth itself. There is an assumption that during the formation of the Earth, the planet's atmosphere was able to capture large volumes of water vapor. Over time, the planet's geological mechanisms, primarily its volcanic activity, released this water vapor into the atmosphere, after which in the atmosphere, this vapor condensed and fell to the surface of the planet in the form of liquid water. Another version suggests that the source of water was comets that fell to the surface of the Earth in the past, ice which predominated in their composition and formed the reservoirs that exist on Earth.

Ground surface

Despite the fact that most of the Earth's surface is located under its oceans, the "dry" surface has many distinctive features. When comparing the Earth to other solid bodies in the solar system, its surface is strikingly different because it does not have craters. According to planetary scientists, this does not mean that the Earth has escaped numerous impacts from small cosmic bodies, but rather indicates that evidence of such impacts has been erased. There may be many geological processes responsible for this, but scientists identify the two most important - weathering and erosion. It is believed that in many ways it was the dual impact of these factors that influenced the erasure of traces of craters from the face of the Earth.

So weathering breaks surface structures into smaller pieces, not to mention chemical and physical methods of atmospheric exposure. An example of chemical weathering is acid rain. An example of physical weathering is the abrasion of river beds caused by rocks contained in flowing water. The second mechanism, erosion, is essentially the effect on the relief of the movement of particles of water, ice, wind or earth. Thus, under the influence of weathering and erosion, the impact craters on our planet were “erased”, due to which some relief features were formed.

Scientists also identify two geological mechanisms that, in their opinion, helped shape the Earth's surface. The first such mechanism is volcanic activity - the process of release of magma (molten rock) from the interior of the Earth through breaks in its crust. Perhaps it was due to volcanic activity that the earth's crust was changed and islands were formed (the Hawaiian Islands are a good example). The second mechanism determines mountain building or the formation of mountains as a result of compression of tectonic plates.

Structure of planet earth

Like other terrestrial planets, the Earth consists of three components: the core, mantle and crust. Science now believes that the core of our planet consists of two separate layers: an inner core of solid nickel and iron and an outer core of molten nickel and iron. At the same time, the mantle is a very dense and almost completely solid silicate rock - its thickness is approximately 2850 km. The bark also consists of silicate rocks and varies in thickness. While continental crust ranges from 30 to 40 kilometers in thickness, oceanic crust is much thinner, only 6 to 11 kilometers.

Another distinctive feature of Earth relative to other terrestrial planets is that its crust is divided into cold, rigid plates that rest on a hotter mantle below. In addition, these plates are in constant motion. Along their boundaries, as a rule, two processes occur simultaneously, known as subduction and spreading. During subduction, two plates come into contact producing earthquakes and one plate rides on the other. The second process is separation, where two plates move away from each other.

Earth's orbit and rotation

It takes the Earth approximately 365 days to complete its orbit around the Sun. The length of our year is related largely to the average orbital distance of the Earth, which is 1.50 x 10 to the power of 8 km. At this orbital distance, it takes on average about eight minutes and twenty seconds for sunlight to reach the Earth's surface.

At an orbital eccentricity of .0167, the Earth's orbit is one of the most circular in the entire solar system. This means that the difference between Earth's perihelion and aphelion is relatively small. As a result of this small difference, the intensity of sunlight on Earth remains essentially the same year-round. However, the position of the Earth in its orbit determines one season or another.

The Earth's axial tilt is approximately 23.45°. In this case, the Earth takes twenty-four hours to complete one rotation around its axis. This is the fastest rotation among the terrestrial planets, but slightly slower than all the gas planets.

In the past, the Earth was considered the center of the Universe. For 2000 years, ancient astronomers believed that the Earth was static and that other celestial bodies traveled in circular orbits around it. They came to this conclusion by observing the obvious movement of the Sun and planets when observed from Earth. In 1543, Copernicus published his heliocentric model of the solar system, which places the Sun at the center of our solar system.

Earth is the only planet in the system that was not named after mythological gods or goddesses (the other seven planets in the solar system were named after Roman gods or goddesses). This refers to the five planets visible to the naked eye: Mercury, Venus, Mars, Jupiter and Saturn. The same approach with the names of the ancient Roman gods was used after the discovery of Uranus and Neptune. The word “Earth” itself comes from the old English word “ertha” meaning soil.

Earth is the densest planet in the solar system. The density of the Earth differs in each layer of the planet (the core, for example, is denser than the crust). The average density of the planet is about 5.52 grams per cubic centimeter.

The gravitational interaction between the Earth causes tides on Earth. It is believed that the Moon is blocked by the Earth's tidal forces, so its rotation period coincides with the Earth's and it always faces our planet with the same side.

The Earth is the object of study for a significant amount of geosciences. The study of the Earth as a celestial body belongs to the field, the structure and composition of the Earth is studied by geology, the state of the atmosphere - meteorology, the totality of manifestations of life on the planet - biology. Geography describes the relief features of the planet's surface - oceans, seas, lakes and waters, continents and islands, mountains and valleys, as well as settlements and societies. education: cities and villages, states, economic regions, etc.

Planetary characteristics

The Earth revolves around the star Sun in an elliptical orbit (very close to circular) with an average speed of 29,765 m/s at an average distance of 149,600,000 km per period, which is approximately equal to 365.24 days. The Earth has a satellite, which revolves around the Sun at an average distance of 384,400 km. The inclination of the earth's axis to the ecliptic plane is 66 0 33 "22". The period of revolution of the planet around its axis is 23 hours 56 minutes 4.1 s. Rotation around its axis causes the change of day and night, and the tilt of the axis and revolution around the Sun causes the change of times of the year.

The shape of the Earth is geoid. The average radius of the Earth is 6371.032 km, equatorial - 6378.16 km, polar - 6356.777 km. The surface area of ​​the globe is 510 million km², volume - 1.083 10 12 km², average density - 5518 kg / m³. The mass of the Earth is 5976.10 21 kg. The earth has a magnetic field and a closely related electric field. The Earth's gravitational field determines its close to spherical shape and the existence of an atmosphere.

According to modern cosmogonic concepts, the Earth was formed approximately 4.7 billion years ago from gaseous matter scattered in the protosolar system. As a result of the differentiation of the Earth's substance, under the influence of its gravitational field, in conditions of heating of the earth's interior, shells of different chemical composition, state of aggregation and physical properties - the geosphere - arose and developed: the core (in the center), the mantle, the earth's crust, the hydrosphere, the atmosphere, the magnetosphere . The composition of the Earth is dominated by iron (34.6%), oxygen (29.5%), silicon (15.2%), magnesium (12.7%). The Earth's crust, mantle, and inner core are solid (the outer core is considered liquid). From the surface of the Earth towards the center, pressure, density and temperature increase. The pressure at the center of the planet is 3.6 10 11 Pa, the density is approximately 12.5 10³ kg/m³, and the temperature ranges from 5000 to 6000 °C. The main types of the earth's crust are continental and oceanic; in the transition zone from the continent to the ocean, crust of an intermediate structure is developed.

Shape of the Earth

The figure of the Earth is an idealization that is used to try to describe the shape of the planet. Depending on the purpose of the description, various models of the shape of the Earth are used.

First approach

The roughest form of description of the figure of the Earth at the first approximation is a sphere. For most problems of general geoscience, this approximation seems sufficient to be used in the description or study of certain geographical processes. In this case, the oblateness of the planet at the poles is rejected as an insignificant remark. The Earth has one axis of rotation and an equatorial plane - a plane of symmetry and a plane of symmetry of meridians, which characteristically distinguishes it from the infinity of sets of symmetry of an ideal sphere. The horizontal structure of the geographic envelope is characterized by a certain zonality and a certain symmetry relative to the equator.

Second approximation

At a closer approach, the figure of the Earth is equated to an ellipsoid of revolution. This model, characterized by a pronounced axis, an equatorial plane of symmetry and meridional planes, is used in geodesy for calculating coordinates, constructing cartographic networks, calculations, etc. The difference between the semi-axes of such an ellipsoid is 21 km, the major axis is 6378.160 km, the minor axis is 6356.777 km, the eccentricity is 1/298.25. The position of the surface can easily be theoretically calculated, but it cannot be determined experimentally in nature.

Third approximation

Since the equatorial section of the Earth is also an ellipse with a difference in the lengths of the semi-axes of 200 m and an eccentricity of 1/30000, the third model is a triaxial ellipsoid. This model is almost never used in geographical studies; it only indicates the complex internal structure of the planet.

Fourth approximation

The geoid is an equipotential surface that coincides with the average level of the World Ocean; it is the geometric locus of points in space that have the same gravitational potential. Such a surface has an irregular complex shape, i.e. is not a plane. The level surface at each point is perpendicular to the plumb line. The practical significance and importance of this model is that only with the help of a plumb line, level, level and other geodetic instruments can one trace the position of level surfaces, i.e. in our case, the geoid.

Ocean and land

A general feature of the structure of the earth's surface is its distribution into continents and oceans. Most of the Earth is occupied by the World Ocean (361.1 million km² 70.8%), land is 149.1 million km² (29.2%), and forms six continents (Eurasia, Africa, North America, South America , and Australia) and islands. It rises above the level of the world's oceans by an average of 875 m (the highest height is 8848 m - Mount Chomolungma), mountains occupy more than 1/3 of the land surface. Deserts cover approximately 20% of the land surface, forests - about 30%, glaciers - over 10%. The height amplitude on the planet reaches 20 km. The average depth of the world's oceans is approximately 3800 m (the greatest depth is 11020 m - the Mariana Trench (trench) in the Pacific Ocean). The volume of water on the planet is 1370 million km³, the average salinity is 35 ‰ (g/l).

Geological structure

Geological structure of the Earth

The inner core is thought to be 2,600 km in diameter and composed of pure iron or nickel, the outer core is 2,250 km thick of molten iron or nickel, and the mantle, about 2,900 km thick, is composed primarily of hard rock, separated from the crust by the Mohorovic surface. The crust and upper mantle form 12 main moving blocks, some of which support continents. Plateaus are constantly moving slowly, this movement is called tectonic drift.

Internal structure and composition of the “solid” Earth. 3. consists of three main geospheres: the earth's crust, mantle and core, which, in turn, is divided into a number of layers. The substance of these geospheres differs in physical properties, condition and mineralogical composition. Depending on the magnitude of the velocities of seismic waves and the nature of their changes with depth, the “solid” Earth is divided into eight seismic layers: A, B, C, D ", D ", E, F and G. In addition, a particularly strong layer is distinguished in the Earth the lithosphere and the next, softened layer - the asthenosphere. Ball A, or the earth's crust, has a variable thickness (in the continental region - 33 km, in the oceanic region - 6 km, on average - 18 km).

The crust thickens under the mountains and almost disappears in the rift valleys of mid-ocean ridges. At the lower boundary of the earth's crust, the Mohorovicic surface, the velocities of seismic waves increase abruptly, which is mainly associated with a change in the material composition with depth, the transition from granites and basalts to ultrabasic rocks of the upper mantle. Layers B, C, D", D" are included in the mantle. Layers E, F and G form the Earth's core with a radius of 3486 km. At the border with the core (Gutenberg surface), the speed of longitudinal waves sharply decreases by 30%, and transverse waves disappear, which means that the outer core (layer E, extends to a depth of 4980 km) liquid Below the transition layer F (4980-5120 km) there is a solid inner core (layer G), in which transverse waves again propagate.

The following chemical elements predominate in the solid crust: oxygen (47.0%), silicon (29.0%), aluminum (8.05%), iron (4.65%), calcium (2.96%), sodium (2.5%), magnesium (1.87%), potassium (2.5%), titanium (0.45%), which add up to 98.98%. The rarest elements: Po (approximately 2.10 -14%), Ra (2.10 -10%), Re (7.10 -8%), Au (4.3 10 -7%), Bi (9 10 -7%) etc.

As a result of magmatic, metamorphic, tectonic and sedimentation processes, the earth's crust is sharply differentiated; complex processes of concentration and dispersion of chemical elements take place in it, leading to the formation of various types of rocks.

The upper mantle is believed to be similar in composition to ultramafic rocks, dominated by O (42.5%), Mg (25.9%), Si (19.0%) and Fe (9.85%). In mineral terms, olivine reigns here, with fewer pyroxenes. The lower mantle is considered an analogue of stony meteorites (chondrites). The core of the earth is similar in composition to iron meteorites and contains approximately 80% Fe, 9% Ni, 0.6% Co. Based on the meteorite model, the average composition of the Earth was calculated, which is dominated by Fe (35%), A (30%), Si (15%) and Mg (13%).

Temperature is one of the most important characteristics of the earth's interior, allowing us to explain the state of matter in various layers and build a general picture of global processes. According to measurements in wells, the temperature in the first kilometers increases with depth with a gradient of 20 °C/km. At a depth of 100 km, where the primary sources of volcanoes are located, the average temperature is slightly lower than the melting point of rocks and is equal to 1100 ° C. At the same time, under the oceans at a depth of 100-200 km the temperature is 100-200 ° C higher than in the continents. The density of matter in layer C at 420 km corresponds to a pressure of 1.4 10 10 Pa and is identified with the phase transition to olivine, which occurs at a temperature of approximately 1600 ° C. At the boundary with the core at a pressure of 1.4 10 11 Pa and temperature At about 4000 °C, silicates are in a solid state, and iron is in a liquid state. In the transition layer F, where iron solidifies, the temperature can be 5000 ° C, in the center of the earth - 5000-6000 ° C, i.e., adequate to the temperature of the Sun.

Earth's atmosphere

The Earth's atmosphere, the total mass of which is 5.15 10 15 tons, consists of air - a mixture of mainly nitrogen (78.08%) and oxygen (20.95%), 0.93% argon, 0.03% carbon dioxide, the rest is water vapor, as well as inert and other gases. The maximum land surface temperature is 57-58 ° C (in the tropical deserts of Africa and North America), the minimum is about -90 ° C (in the central regions of Antarctica).

The Earth's atmosphere protects all living things from the harmful effects of cosmic radiation.

Chemical composition of the Earth's atmosphere: 78.1% - nitrogen, 20 - oxygen, 0.9 - argon, the rest - carbon dioxide, water vapor, hydrogen, helium, neon.

The Earth's atmosphere includes :

• troposphere (up to 15 km)
• stratosphere (15-100 km)
• ionosphere (100 - 500 km).

Between the troposphere and stratosphere there is a transition layer - the tropopause. In the depths of the stratosphere, under the influence of sunlight, an ozone shield is created that protects living organisms from cosmic radiation. Above are the meso-, thermo- and exospheres.

Weather and climate

The lower layer of the atmosphere is called the troposphere. Phenomena that determine the weather occur in it. Due to the uneven heating of the Earth's surface by solar radiation, large masses of air constantly circulate in the troposphere. The main air currents in the Earth's atmosphere are the trade winds in the band up to 30° along the equator and the westerly winds of the temperate zone in the band from 30° to 60°. Another factor in heat transfer is the ocean current system.

Water has a constant cycle on the surface of the earth. Evaporating from the surface of water and land, under favorable conditions, water vapor rises up in the atmosphere, which leads to the formation of clouds. Water returns to the surface of the earth in the form of precipitation and flows down to the seas and oceans throughout the year.

The amount of solar energy that the Earth's surface receives decreases with increasing latitude. The further from the equator, the smaller the angle of incidence of the sun's rays on the surface, and the greater the distance that the ray must travel in the atmosphere. As a consequence, the average annual temperature at sea level decreases by about 0.4 °C per degree of latitude. The surface of the Earth is divided into latitudinal zones with approximately the same climate: tropical, subtropical, temperate and polar. The classification of climates depends on temperature and precipitation. The most widely recognized is the Köppen climate classification, which distinguishes five broad groups - humid tropics, desert, humid mid-latitudes, continental climate, cold polar climate. Each of these groups is divided into specific groups.

Human influence on the Earth's atmosphere

The Earth's atmosphere is significantly influenced by human activity. About 300 million cars annually emit 400 million tons of carbon oxides, more than 100 million tons of carbohydrates, and hundreds of thousands of tons of lead into the atmosphere. Powerful producers of atmospheric emissions: thermal power plants, metallurgical, chemical, petrochemical, pulp and other industries, motor vehicles.

Systematic inhalation of polluted air significantly worsens people's health. Gaseous and dust impurities can give the air an unpleasant odor, irritate the mucous membranes of the eyes and upper respiratory tract and thereby reduce their protective functions, and cause chronic bronchitis and lung diseases. Numerous studies have shown that against the background of pathological abnormalities in the body (diseases of the lungs, heart, liver, kidneys and other organs), the harmful effects of atmospheric pollution are more pronounced. Acid rain has become an important environmental problem. Every year, when burning fuel, up to 15 million tons of sulfur dioxide enters the atmosphere, which, when combined with water, forms a weak solution of sulfuric acid, which falls to the ground along with rain. Acid rain negatively affects people, crops, buildings, etc.

Ambient air pollution can also indirectly affect the health and sanitary living conditions of people.

The accumulation of carbon dioxide in the atmosphere can cause climate warming as a result of the greenhouse effect. Its essence is that the layer of carbon dioxide, which freely transmits solar radiation to the Earth, will delay the return of thermal radiation to the upper atmosphere. In this regard, the temperature in the lower layers of the atmosphere will increase, which, in turn, will lead to the melting of glaciers, snow, rising levels of oceans and seas, and flooding of a significant part of the land.

Story

The Earth formed approximately 4540 million years ago from a disk-shaped protoplanetary cloud along with the other planets of the solar system. The formation of the Earth as a result of accretion lasted 10-20 million years. At first the Earth was completely molten, but gradually cooled, and a thin solid shell formed on its surface - the earth's crust.

Shortly after the formation of the Earth, approximately 4530 million years ago, the Moon formed. The modern theory of the formation of a single natural satellite of the Earth claims that this happened as a result of a collision with a massive celestial body, which was called Theia.
The Earth's primary atmosphere was formed as a result of degassing of rocks and volcanic activity. Water condensed from the atmosphere to form the World Ocean. Despite the fact that the Sun by that time was 70% weaker than it is now, geological data shows that the ocean did not freeze, which may be due to the greenhouse effect. About 3.5 billion years ago, the Earth's magnetic field formed, protecting its atmosphere from the solar wind.

The formation of the Earth and the initial stage of its development (lasting approximately 1.2 billion years) belong to pre-geological history. The absolute age of the oldest rocks is over 3.5 billion years and, starting from this moment, the geological history of the Earth begins, which is divided into two unequal stages: the Precambrian, which occupies approximately 5/6 of the entire geological chronology (about 3 billion years), and Phanerozoic, covering the last 570 million years. About 3-3.5 billion years ago, as a result of the natural evolution of matter, life arose on Earth, the development of the biosphere began - the totality of all living organisms (the so-called living matter of the Earth), which significantly influenced the development of the atmosphere, hydrosphere and geosphere (at least in parts of the sedimentary shell). As a result of the oxygen catastrophe, the activity of living organisms changed the composition of the Earth's atmosphere, enriching it with oxygen, which created the opportunity for the development of aerobic living beings.

A new factor that has a powerful influence on the biosphere and even the geosphere is the activity of mankind, which appeared on Earth after the appearance of man as a result of evolution less than 3 million years ago (unity regarding dating has not been achieved and some researchers believe - 7 million years ago). Accordingly, in the process of development of the biosphere, formations and further development of the noosphere are distinguished - the shell of the Earth, which is greatly influenced by human activity.

The high growth rate of the Earth's population (the world's population was 275 million in 1000, 1.6 billion in 1900 and approximately 6.7 billion in 2009) and the increasing influence of human society on the natural environment have raised problems of rational use of all natural resources and protection nature.

Earth- the third planet of the solar system. Find out the description of the planet, mass, orbit, size, interesting facts, distance to the Sun, composition, life on Earth.

Of course we love our planet. And not only because this is our home, but also because this is a unique place in the solar system and the Universe, because so far we only know life on Earth. Lives in the inner part of the system and occupies a place between Venus and Mars.

Planet Earth also called the Blue Planet, Gaia, World and Terra, which reflects its role for each people in historical terms. We know that our planet is rich in many different forms of life, but how exactly did it manage to become so? First, consider some interesting facts about Earth.

Interesting facts about planet Earth

Rotation gradually slows down

• For earthlings, the entire process of slowing down the rotation of the axis occurs almost imperceptibly - 17 milliseconds per 100 years. But the nature of the speed is not uniform. Because of this, the length of the day increases. In 140 million years, a day will cover 25 hours.

Believed that the Earth was the center of the Universe

• Ancient scientists could observe celestial objects from the position of our planet, so it seemed that all objects in the sky were moving relative to us, and we remained at one point. As a result, Copernicus stated that the Sun (the heliocentric system of the world) is at the center of everything, although now we know that this does not correspond to reality, if we take the scale of the Universe.

Endowed with a powerful magnetic field

• The Earth's magnetic field is created by the nickel-iron planetary core, which rotates rapidly. The field is important because it protects us from the influence of the solar wind.

Has one satellite

• If you look at the percentage, the Moon is the largest satellite in the system. But in reality it is in 5th position in size.

The only planet not named after a deity

• Ancient scientists named all 7 planets in honor of the gods, and modern scientists followed the tradition when discovering Uranus and Neptune.

First in density

• Everything is based on the composition and specific part of the planet. So the core is represented by metal and bypasses the crust in density. The average density of the earth is 5.52 grams per cm 3.

Size, mass, orbit of planet Earth

With a radius of 6371 km and a mass of 5.97 x 10 24 kg, the Earth ranks 5th in size and massiveness. It is the largest terrestrial planet, but it is smaller in size than the gas and ice giants. However, in terms of density (5.514 g/cm3) it ranks first in the Solar System.

Polar compression	0,0033528
Equatorial	6378.1 km
Polar radius	6356.8 km
Average radius	6371.0 km
Great circle circumference	40,075.017 km (equator) (meridian)
Surface area	510,072,000 km²
Volume	10.8321 10 11 km³
Weight	5.9726 10 24 kg
Average density	5.5153 g/cm³
Acceleration free falls at the equator	9.780327 m/s²
First escape velocity	7.91 km/s
Second escape velocity	11.186 km/s
Equatorial speed rotation	1674.4 km/h
Rotation period	(23 h 56 m 4,100 s)
Axis tilt	23°26’21",4119
Albedo	0.306 (Bond) 0.367 (geom.)

There is a slight eccentricity in the orbit (0.0167). The distance from the star at perihelion is 0.983 AU, and at aphelion – 1.015 AU.

One passage around the Sun takes 365.24 days. We know that due to the existence of leap years, we add a day every 4 passes. We are used to thinking that a day lasts 24 hours, but in reality this time takes 23 hours 56 minutes and 4 seconds.

If you observe the rotation of the axis from the poles, you can see that it occurs counterclockwise. The axis is inclined at 23.439281° from the perpendicular to the orbital plane. This affects the amount of light and heat.

If the North Pole is turned towards the Sun, then summer occurs in the northern hemisphere, and winter in the southern hemisphere. At a certain time, the Sun does not rise at all over the Arctic Circle, and then night and winter last there for 6 months.

Composition and surface of planet Earth

The shape of planet Earth is like a spheroid, flattened at the poles and with a convexity at the equatorial line (diameter - 43 km). This happens due to rotation.

The structure of the Earth is represented by layers, each of which has its own chemical composition. It differs from other planets in that our core has a clear distribution between the solid inner (radius - 1220 km) and the liquid outer (3400 km).

Next comes the mantle and crust. The first deepens to 2890 km (the densest layer). It is represented by silicate rocks with iron and magnesium. The crust is divided into lithosphere (tectonic plates) and asthenosphere (low viscosity). You can carefully examine the structure of the Earth in the diagram.

The lithosphere breaks down into solid tectonic plates. These are rigid blocks that move relative to each other. There are points of connection and break. It is their contact that leads to earthquakes, volcanic activity, the creation of mountains and ocean trenches.

There are 7 main plates: Pacific, North American, Eurasian, African, Antarctic, Indo-Australian and South American.

Our planet is notable for the fact that approximately 70.8% of its surface is covered with water. The bottom map of the Earth shows tectonic plates.

The earth's landscape is different everywhere. The submerged surface resembles mountains and has underwater volcanoes, oceanic trenches, canyons, plains and even oceanic plateaus.

During the development of the planet, the surface was constantly changing. Here it is worth considering the movement of tectonic plates, as well as erosion. It also affects the transformation of glaciers, the creation of coral reefs, meteorite impacts, etc.

Continental crust is represented by three varieties: magnesium rocks, sedimentary and metamorphic. The first is divided into granite, andesite and basalt. Sedimentary makes up 75% and is created by burying accumulated sediment. The latter is formed during the icing of sedimentary rock.

From the lowest point, the surface height reaches -418 m (at the Dead Sea) and rises to 8848 m (the top of Everest). The average height of the land above sea level is 840 m. The mass is also divided between the hemispheres and continents.

The outer layer contains soil. This is a certain line between the lithosphere, atmosphere, hydrosphere and biosphere. Approximately 40% of the surface is used for agricultural purposes.

Atmosphere and temperature of planet Earth

There are 5 layers of the earth's atmosphere: troposphere, stratosphere, mesosphere, thermosphere and exosphere. The higher you rise, the less air, pressure and density you will feel.

The troposphere is located closest to the surface (0-12 km). Contains 80% of the mass of the atmosphere, with 50% located within the first 5.6 km. It consists of nitrogen (78%) and oxygen (21%) with admixtures of water vapor, carbon dioxide and other gaseous molecules.

In the interval of 12-50 km we see the stratosphere. It is separated from the first tropopause - a line with relatively warm air. This is where the ozone layer is located. The temperature rises as the layer absorbs ultraviolet light. The atmospheric layers of the Earth are shown in the figure.

This is a stable layer and is practically free from turbulence, clouds and other weather formations.

At an altitude of 50-80 km there is the mesosphere. This is the coldest place (-85°C). It is located near the mesopause, extending from 80 km to the thermopause (500-1000 km). The ionosphere lives within the range of 80-550 km. Here the temperature increases with altitude. In the photo of the Earth you can admire the northern lights.

The layer is devoid of clouds and water vapor. But it is here that auroras form and the International Space Station is located (320-380 km).

The outermost sphere is the exosphere. This is a transition layer to outer space, devoid of an atmosphere. Represented by hydrogen, helium and heavier molecules with low density. However, the atoms are so scattered that the layer does not behave like a gas, and particles are constantly being removed into space. Most of the satellites live here.

This mark is influenced by many factors. The Earth makes an axial revolution every 24 hours, which means one side always experiences night and lower temperatures. In addition, the axis is tilted, so the northern and southern hemispheres alternately move away and move closer.

All this creates seasonality. Not every part of the earth experiences sharp drops and rises in temperatures. For example, the amount of light entering the equatorial line remains virtually unchanged.

If we take the average, we get 14°C. But the maximum was 70.7°C (Lut Desert), and the minimum of -89.2°C was reached at the Soviet Vostok station on the Antarctic plateau in July 1983.

Moon and asteroids of the Earth

The planet has only one satellite, which affects not only the physical changes of the planet (for example, the ebb and flow of tides), but is also reflected in history and culture. To be precise, the Moon is the only celestial body on which a person has walked. This happened on July 20, 1969 and the right to take the first step went to Neil Armstrong. Overall, 13 astronauts landed on the satellite.

The Moon appeared 4.5 billion years ago due to the collision of the Earth and a Martian-sized object (Theia). We can be proud of our satellite, because it is one of the largest moons in the system, and also ranks second in density (after Io). It is in gravitational locking (one side always faces the Earth).

The diameter covers 3474.8 km (1/4 of the Earth), and the mass is 7.3477 x 10 22 kg. The average density is 3.3464 g/cm3. In terms of gravity it reaches only 17% of the Earth's. The moon influences the earth's tides, as well as the activity of all living organisms.

Don't forget that there are lunar and solar eclipses. The first happens when the Moon falls into the Earth's shadow, and the second happens when a satellite passes between us and the Sun. The satellite's atmosphere is weak, causing temperatures to fluctuate greatly (from -153°C to 107°C).

Helium, neon and argon can be found in the atmosphere. The first two are created by the solar wind, and argon is due to the radioactive decay of potassium. There is also evidence of frozen water in craters. The surface is divided into different types. There is Maria - flat plains that ancient astronomers mistook for seas. Terras are lands, like highlands. Even mountainous areas and craters can be seen.

The Earth has five asteroids. Satellite 2010 TK7 resides at L4, and asteroid 2006 RH120 approaches the Earth-Moon system every 20 years. If we talk about artificial satellites, there are 1265 of them, as well as 300,000 pieces of debris.

Formation and evolution of planet Earth

In the 18th century, humanity came to the conclusion that our terrestrial planet, like the entire solar system, emerged from a nebulous cloud. That is, 4.6 billion years ago, our system resembled a circumstellar disk, represented by gas, ice and dust. Then most of it approached the center and, under pressure, transformed into the Sun. The remaining particles created the planets we know.

The primordial Earth appeared 4.54 billion years ago. From the very beginning, it was molten due to volcanoes and frequent collisions with other objects. But 4-2.5 billion years ago, solid crust and tectonic plates appeared. Degassing and volcanoes created the first atmosphere, and ice arriving on comets formed the oceans.

The surface layer did not remain frozen, so the continents converged and moved apart. About 750 million years ago, the very first supercontinent began to break apart. Pannotia was created 600-540 million years ago, and the last one (Pangea) collapsed 180 million years ago.

The modern picture was created 40 million years ago and took hold 2.58 million years ago. The last ice age, which began 10,000 years ago, is currently underway.

It is believed that the first hints of life on Earth appeared 4 billion years ago (Archean eon). Due to chemical reactions, self-replicating molecules appeared. Photosynthesis created molecular oxygen, which, together with ultraviolet rays, formed the first ozone layer.

Then various multicellular organisms began to appear. Microbial life arose 3.7-3.48 billion years ago. 750-580 million years ago, most of the planet was covered with glaciers. Active reproduction of organisms began during the Cambrian explosion.

Since that time (535 million years ago), history includes 5 major extinction events. The last one (the death of dinosaurs from a meteorite) happened 66 million years ago.

They were replaced by new species. The African ape-like animal stood on its hind legs and freed its forelimbs. This stimulated the brain to use different tools. Then we know about the development of agricultural crops, socialization and other mechanisms that led us to modern man.

Reasons for the habitability of planet Earth

If a planet meets a number of conditions, then it is considered potentially habitable. Now the Earth is the only lucky one with developed life forms. What is needed? Let's start with the main criterion - liquid water. In addition, the main star must provide enough light and heat to maintain the atmosphere. An important factor is location in the habitat zone (the distance of the Earth from the Sun).

We should understand how lucky we are. After all, Venus is similar in size, but due to its close location to the Sun, it is a hellishly hot place with acid rain. And Mars, which lives behind us, is too cold and has a weak atmosphere.

Planet Earth Research

The first attempts to explain the origin of the Earth were based on religion and myths. Often the planet became a deity, namely a mother. Therefore, in many cultures, the history of everything begins with the mother and the birth of our planet.

There are also a lot of interesting things in the form. In ancient times, the planet was considered flat, but different cultures added their own characteristics. For example, in Mesopotamia, a flat disk floated in the middle of the ocean. The Mayans had 4 jaguars that held up the heavens. For the Chinese it was generally a cube.

Already in the 6th century BC. e. scientists sewed it onto a round shape. Surprisingly, in the 3rd century BC. e. Eratosthenes even managed to calculate the circle with an error of 5-15%. The spherical shape became established with the advent of the Roman Empire. Aristotle spoke about changes in the earth's surface. He believed that it happens too slowly, so a person is not able to catch it. This is where attempts to understand the age of the planet arise.

Scientists are actively studying geology. The first catalog of minerals was created by Pliny the Elder in the 1st century AD. In 11th century Persia, explorers studied Indian geology. The theory of geomorphology was created by the Chinese naturalist Shen Guo. He identified marine fossils located far from the water.

In the 16th century, understanding and exploration of the Earth expanded. We should thank the heliocentric model of Copernicus, which proved that the Earth is not the universal center (previously the geocentric system was used). And also Galileo Galilei for his telescope.

In the 17th century, geology became firmly established among other sciences. They say that the term was coined by Ulysses Aldvandi or Mikkel Eschholt. The fossils discovered at that time caused serious controversy in the age of the earth. All the religious people insisted on 6000 years (as the Bible said).

This debate ended in 1785 when James Hutton declared that the Earth was much older. It was based on the erosion of rocks and the calculation of the time required for this. In the 18th century, scientists were divided into 2 camps. The former believed that the rocks were deposited by floods, while the latter complained about the fiery conditions. Hutton stood in firing position.

The first geological maps of the Earth appeared in the 19th century. The main work is “Principles of Geology”, published in 1830 by Charles Lyell. In the 20th century, age calculations became much easier thanks to radiometric dating (2 billion years). However, the study of tectonic plates has already led to the modern mark of 4.5 billion years.

The future of planet Earth

Our life depends on the behavior of the Sun. However, each star has its own evolutionary path. It is expected that in 3.5 billion years it will increase in volume by 40%. This will increase the flow of radiation, and the oceans may simply evaporate. Then the plants will die, and in a billion years all living things will disappear, and the constant average temperature will be fixed at around 70°C.

In 5 billion years, the Sun will transform into a red giant and shift our orbit by 1.7 AU.

If you look at the entire history of the earth, then humanity is just a fleeting blip. However, the Earth remains the most important planet, home and unique place. One can only hope that we will have time to populate other planets outside our system before the critical period of solar development. Below you can explore a map of the Earth's surface. In addition, our website contains many beautiful high-resolution photos of the planet and places on Earth from space. Using online telescopes from the ISS and satellites, you can observe the planet for free in real time.

Click on the image to enlarge it