• Earth is 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 currently known to man, the Solar System in particular and the Universe in general, inhabited by living organisms.

  Scientific evidence indicates that the Earth formed from a solar nebula about 4.54 billion years ago and acquired its only natural satellite, the Moon, shortly thereafter. Presumably, life appeared on Earth approximately 4.25 billion years ago, that is, shortly after its origin. Since then, the Earth's biosphere has significantly changed the atmosphere and other abiotic factors, causing a quantitative increase in aerobic organisms, as well as the formation of the ozone layer, which, together with the Earth's magnetic field, weakens solar radiation harmful to life, thereby maintaining the conditions for the existence of life on Earth. Radiation caused by the earth's crust itself has decreased significantly since its formation due to the gradual decay of radionuclides in it. The Earth's crust is divided into several segments, or tectonic plates, which move across the surface at speeds of the order of several centimeters per year. The science of geology studies the composition, structure and patterns of development of the Earth.

  Approximately 70.8% of the planet's surface is occupied by the World Ocean, the rest of the surface is occupied by continents and islands. The continents contain rivers, lakes, groundwater and ice; together with the World Ocean they make up the hydrosphere. Liquid water, essential for all known life forms, does not exist on the surface of any known planets or planetoids in the Solar System other than Earth. The Earth's poles are covered by a shell of ice that includes Arctic sea ice and the Antarctic ice sheet.

  The Earth's interior is quite active and consists of a thick, highly viscous layer called the mantle, which covers a liquid outer core, the source of the Earth's magnetic field, and a solid inner core, presumably composed of iron and nickel. 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 surface of the planet 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, in particular causing mass extinctions of various species of living beings.

  The planet is home to millions of species of living beings, including humans. The territory of the Earth is divided into 195 independent states that interact with each other. Human culture has formed many ideas about the structure of the universe - such as the concept of a flat Earth, the geocentric system of the world and the Gaia hypothesis, according to which the Earth is a single superorganism.

Our planet - Earth - has many names: the blue planet, Terra (lat.), the third planet, Earth (eng.). It revolves around the Sun in a circular orbit with a radius of about 1 astronomical unit (150 million km). The orbital period occurs at a speed of 29.8 km/s and lasts 1 year (365 days). Its age is comparable to the age of the entire solar system, and is 4.5 billion years. Modern science believes that the Earth was formed from dust and gas that remained from the formation of the Sun. From the fact that elements with high density are located at great depths, and light substances (silicates of various metals) remained on the surface, a logical conclusion follows - the Earth, at the beginning of its formation, was in a molten state. Now, the temperature of the planet's core is within 6200 °C. After the high temperatures subsided, it began to harden. Huge areas of the Earth are still covered with water, without which the emergence of life would have been impossible.

The main core of the Earth is divided into an inner solid core with a radius of 1300 km and an outer liquid core (2200 km). The temperature in the center of the core reaches 5000 °C. The mantle extends to a depth of 2900 km and makes up 83% of the Earth's volume and 67% of its total mass. It has a rocky appearance and consists of 2 parts: external and internal. Lithosphere is the outer part of the mantle, about 100 km long. The Earth's crust is the upper part of the lithosphere of uneven thickness: about 50 km on the continents and about 10 km under the oceans. The lithosphere consists of large plates, the size of which reaches entire continents. The movement of these plates, under the influence of convective flows, was called by geologists “the movement of tectonic plates.”

A magnetic field

Essentially, the Earth is a direct current generator. The Earth's magnetic field arises due to the interaction of rotation around its own axis with the liquid core inside the planet. It forms the magnetic shell of the Earth - the “magnetosphere”. Magnetic storms are sudden changes in the Earth's magnetic field. They are caused by streams of particles of ionized gas that move from the Sun (solar wind), after flares on it. Particles colliding with atoms of the earth's atmosphere form one of the most beautiful natural phenomena - auroras. A special glow usually occurs near the North and South Poles, which is why it is also called the Northern Lights. Analysis of the structure of ancient rocky formations showed that once every 100,000 years, an inversion (change) of the North and South Poles occurs. Scientists cannot yet say exactly how this process occurs, but they are struggling to answer this question.

Previously, the atmosphere of our planet included methane with water vapor and carbon dioxide, hydrogen and ammonia. Subsequently, most of the elements went into space. They were replaced by water vapor and carbon anhydrite. The atmosphere is held in place by the force of earth's gravity. It has several layers.

The troposphere is the lowest and densest layer of the earth's atmosphere, in which the temperature drops with height by 6 °C for every kilometer. Its height reaches 12 km from the Earth's surface.
The stratosphere is a part of the atmosphere located at a distance of 12 to 50 km, between the troposphere and mesosphere. It contains a lot of ozone, and the temperature increases slightly with altitude. Ozone absorbs ultraviolet radiation emanating from the Sun, thereby protecting living organisms from radiation.
The mesosphere is a layer of the atmosphere lying below the thermosphere, at an altitude of 50 to 85 km. It is characterized by low temperatures up to -90 °C, which decreases with altitude.
Thermosphere is a layer of the atmosphere located at an altitude of 85 to 800 km, between the mesosphere and exosphere. Characterized by temperatures up to 1500 °C, falling with altitude.
The exosphere, the outer and last layer of the atmosphere, is the most rarefied and passes into interplanetary space. It is characterized by an altitude of more than 800 km.

Life in the Earth

The average temperature on Earth hovers around 12 °C. The maximum in Western Sahara reaches +70 °C, the minimum in Antarctica reaches –85 °C. The water shell of the Earth - the hydrosphere - occupies 71%, 2/3 or 361 million km2, of the Earth's surface. The Earth's oceans contain 97% of all water reserves. Some is in the form of snow and ice, and some is present in the atmosphere. The depth of the world's oceans in the Mariana Trench is 11 thousand m, and the average depth is about 3.9 thousand m. Both on the continents and in the oceans, there are very diverse and amazing forms of life. Scientists of all times have wrestled with the question: where did life on Earth come from? Naturally, there is simply no clear and precise answer to this question. There can only be guesses and assumptions.

One of the versions that is considered the most reliable and fits numerous criteria, uniting various opinions, is the chemical reactions of gases. Allegedly, favorable conditions for the formation of life appeared thanks to electrical and magnetic storms that caused these reactions of gases that were in the then existing atmosphere. The products of such chemical reactions contained the most elementary particles that were part of proteins (amino acids). These substances entered the oceans and continued their reactions there. And only after many millions of years, the first simplest, primitive cells capable of reproduction or division developed. Hence the explanation that life on Earth originated from water. Plant cells synthesized various molecules and were powered by carbonic anhydride. Plants still do this process today, it is called photosynthesis. As a result of photosynthesis, oxygen accumulated in our atmosphere, which changed its composition and properties. As a result of evolution, the diversity of living beings on the planet grew, but to maintain their life, oxygen was needed. So, without the strong shield of our planet - the stratosphere, which protects all living things from radioactive solar radiation, and oxygen - produced by plants, life on earth might not exist.

Characteristics of the Earth

Weight: 5.98*1024kg
Diameter at the equator: 12,742 km
Axle tilt: 23.5°
Density: 5.52 g/cm3
Surface temperature: –85 °C to +70 °C
Duration of sidereal day: 23 hours, 56 minutes, 4 seconds
Distance from the Sun (average): 1 a. e. (149.6 million km)
Orbital speed: 29.7 km/s
Orbital period (year): 365.25 days
Orbital eccentricity: e = 0.017
Orbital inclination to the ecliptic: i = 7.25° (to the solar equator)
Gravity acceleration: g = 9.8 m/s2
Satellites: Moon

The Earth is in third place in terms of distance from the Sun. It belongs to the class of terrestrial planets and is the largest in this group. As far as we currently know, what makes Earth unique is that it has life. It was found that age of the earth is about 4.54 billion years old. It was formed from cosmic dust and gas - these were substances left after the Sun was formed.

In the initial period of its existence, our planet was in a liquid state. But over time, the reactions slowed down, the temperature dropped, and the Earth's surface began to take a solid form. Gradually an atmosphere began to form. Water appeared on the surface - it entered the atmosphere in the form of ice along with asteroids and other small celestial bodies. The impact of falling comets and asteroids influenced the geographic relief of the Earth, temperature and other climatic conditions on its surface.

How did the satellite of our planet appear? Scientists believe that the Moon was formed as a result of a global astronomical catastrophe, when the Earth tangentially collided with a huge celestial body, not inferior in size to itself. From the fragments of this asteroid a ring was formed around the Earth, which gradually transformed into the Moon. The Moon has a noticeable influence on our planet, it causes the ebb and flow of the world's oceans, and even leads to a slowdown in the Earth's movement.

After the emergence of oceans, oxygen began to accumulate in the atmosphere of our planet. There is still no unambiguous theory of the origin of life on earth, but it is believed that as a result of various chaotic interactions of cells with each other, more and more complexly organized cells were formed, which gave rise to the simplest multicellular creatures. Gradually, life developed, and over time, the ozone layer allowed living organisms to reach land.

The surface of the Earth is not static. Continents are in motion, and what can now be seen on the map is the result of constant change. It is believed that the first supercontinent, as a result of some internal or external influences, split into pieces and about 550 million years ago formed a new supercontinent Pannotia, and later Pangea, which also began to split about 200 million years ago.

Coastal areas often have a milder climate than areas further inland. For example, climate can be influenced by sea and coastal breezes. The surface of the Earth is heating up many times faster than the waters of the sea. During the daytime, warm air rises from below, while at the same time, cold air that comes from the sea takes the place of the warmer air that leaves. As night falls, the reverse process begins to occur. Due to the fact that the water in the sea cools much slower than the land, breezes from the land blow to the sea.

The temperature regime is also influenced by numerous ocean currents. The Atlantic Ocean is crossed diagonally by the warm Gulf Stream, starting its crossing in the Gulf of Mexico and ending at the northwestern European coast. The sea winds that blow over the Gulf Stream towards the coast create a rather mild climate for this part of Europe, milder than on the coasts of North America, located at the same latitudes. Cold ocean currents also influence the climate. Let’s say that the Benguela Current off the African coasts of the southwestern regions and the western South American coasts cools the tropical zones, otherwise it would be much hotter there.

In the central parts of the continents, far from the moderating influences of the sea, one can observe a harsh continental climate, which has both hot summers and cold winters.

The word “continent” has Latin roots and if we literally translate the word “continere”, we get the phrase “to stick together”, this word is not always applied to land, but at the same time it implies unity in structure.

The largest continent on Earth is Eurasia. Eurasia includes Europe and Asia, these are two parts of the world in which most of the earth's population lives.

Africa is the Earth's second largest continent, stretching on both sides of the equator.

South America, together with North America, are located in the western part of the Earth, as well as Africa on both sides of the equator. Since these two continents are connected by the narrow Isthmus of Panama, then, in fact, this continent should be considered one large one.

The smallest continent on Earth is Australia. It is almost 100% located in the hot zone in the southern hemisphere.

The highest continent on Earth is Antarctica. This continent is also the most severe in terms of all biological living conditions.

As for countries, they are classified in a variety of ways. For example, they can be classified depending on the size of the territory (the area of ​​Russia is 17 million square kilometers). Countries are also classified according to the characteristics of the natural world and location, such as tropical European or, for example, mountainous countries. A classification takes place, taking into account the diversity and national composition of the population (Slavic, mono, Roman, multinational countries), taking into account the forms of government and the type of political regime. Also classified by degree of independence. The largest countries in the world are identified by various criteria, most often the countries that occupy the largest area are called the largest.

The largest countries in the world by area are:

1. Russian Federation – 17,075,400 sq. km.

2. Canada – 9,984,670 sq. km.

3. China – 9,596,960 sq. km.

It is rare to hear that China is considered the largest country on Earth. This option is also correct, because here is the largest population. Finally, there are eight countries in the world that are the largest in terms of their economic achievements.

These countries form the G8: Russia, Japan, Italy, Canada, Germany, France, Great Britain, and the leader of the entire chain is the United States, which usually stands out of competition because it has the highest global GDP. India is a country with the most diverse ethnicity. There are more than five thousand nationalities, peoples and tribes on the territory of India.

Currently, the surface of the Earth, in addition to Antarctica and its islands, is shared by about two hundred states.

Antarctica is the largest geographical territory that does not belong to any country on planet Earth. The international treaty states that only scientific activities can be carried out in Antarctica and the unique nature of this continent must always be preserved.

On our website you can view it from the International Space Station, as well as view it completely free of charge.

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.

It is so nice to know that planet Earth has proven to be the most suitable for various forms of life. The temperature conditions here are ideal, there is enough air, oxygen and safe light. It's hard to believe that once upon a time none of this existed. Or almost nothing but a molten cosmic mass of indeterminate shape, floating in zero gravity. But first things first.

Explosion on a universal scale

Early theories of the origin of the universe

Scientists have put forward various hypotheses to explain the birth of the Earth. In the 18th century, the French claimed that the cause was a cosmic catastrophe resulting from the collision of the Sun with a comet. The British claimed that an asteroid flying past the star cut off part of it, from which a whole series of celestial bodies subsequently appeared.

German minds have moved further. They considered a cold dust cloud of incredible size to be the prototype for the formation of planets in the solar system. Later they decided that the dust was hot. One thing is clear: the formation of the Earth is inextricably linked with the formation of all the planets and stars that make up the solar system.

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At what speed does the Earth move around its axis and the Sun?

Today, astronomers and physicists are unanimous in the opinion that the Universe was formed after Big Bang. Billions of years ago, a giant fireball exploded into pieces in outer space. This caused a gigantic ejection of matter, the particles of which had colossal energy. It was the power of the latter that prevented the elements from creating atoms, forcing them to repel each other. This was also facilitated by high temperatures (about a billion degrees). But after a million years, space cooled to approximately 4000º. From this moment, the attraction and formation of atoms of light gaseous substances (hydrogen and helium) began.

Over time, they grouped into clusters called nebulae. These were the prototypes of future celestial bodies. Gradually, the particles inside spun faster and faster, increasing in temperature and energy, causing the nebula to shrink. Having reached a critical point, at a certain moment a thermonuclear reaction began, promoting the formation of a nucleus. Thus the bright Sun was born.

The emergence of the Earth - from gas to solid

The young star had powerful gravitational forces. Their influence caused the formation of other planets at different distances from accumulations of cosmic dust and gases, including the Earth. If you compare the composition of different celestial bodies of the solar system, it will become noticeable that they are not the same.

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Earth collisions with meteorites

Mercury is mainly composed of a metal that is most resistant to sunlight. Venus and Earth have a rocky surface. But Saturn and Jupiter remain gas giants due to their greatest distance. By the way, they protect other planets from meteorites, pushing them away from their orbits.

Formation of the Earth

The formation of the Earth began according to the same principle that underlay the appearance of the Sun itself. This happened approximately 4.6 billion years ago. Heavy metals (iron, nickel) as a result of gravity and compression penetrated into the center of the young planet, forming the core. The high temperature created all the conditions for a series of nuclear reactions. A separation of the mantle and core occurred.

The heat generated melted and ejected light silicon to the surface. It became the prototype of the first crust. As the planet cooled, volatile gases burst out from the depths. This was accompanied by volcanic eruptions. Molten lava later formed rocks.

Gas mixtures were held at a distance around the Earth by gravity. They formed an atmosphere, initially without oxygen. Encounters with icy comets and meteorites led to the appearance of oceans from condensation of vapors and melted ice. Continents separated and reconnected, floating in a hot mantle. This was repeated many times over almost 4 billion years.