The order of the planets of the solar system. Characteristics of celestial bodies of the solar system

Earth - planet Solar system. Earth- one of the celestial bodies that revolve around the Sun. Sun is a star, a flaming ball around which planets revolve. They, together with the Sun, their satellites, many small planets (asteroids), comets and meteor dust, make up solar system . Our galaxy - Milky Way , its diameter is approximately 100 thousand light years (this is how long it will take light to reach the last point of a given space).

Earth- third in a row eight planets , it has a diameter of about 13 thousand km. She's in the distance 150 million km from the Sun (third from the Sun). The Earth, along with Venus, Mars and Mercury, enters inner (terrestrial) group planets. The Earth makes one revolution around the Sun in 365 days 5 hours 48 minutes, or for one year. The Earth's path around the Sun (Earth's orbit) is close in shape to a circle.

Earth, like other planets, spherical . As a result of rotation around its axis, it is slightly flattened at the poles. Due to the inhomogeneous structure of the Earth's interior and the inhomogeneous distribution of masses, the shape of the Earth deviates from the regular shape of an ellipsoid of revolution. True geometric figure The earth was named geoid(earth-like). Geoid - a figure whose surface is everywhere perpendicular to the direction of gravity. The shapes of a spheroid and a geoid do not coincide. Differences are observed within the range of 50-150 m.

Rotation of the Earth.

Simultaneously with its movement around the Sun, the Earth rotates around its axis, turning towards the Sun first with one hemisphere, then with the other. Rotation period equal to approximately 24 hours, or one day. Earth's axis is an imaginary straight line passing through the center of the Earth. The axis intersects the Earth's surface at two points: North and South poles. At equal distances from the geographic poles it passes equator- an imaginary line that divides the Earth into two equal hemispheres: Northern and Southern.

The imaginary axis around which the Earth rotates is inclined to the orbital plane along which the Earth revolves around the Sun. Because of this, at different times of the year the Earth is turned towards the Sun, first with one pole, then with the other. When the area around the North Pole faces the Sun, it is summer in the Northern Hemisphere (in which we live), and winter in the Southern Hemisphere. When the area around is facing the Sun South Pole, then vice versa: in the Southern Hemisphere it is summer, and in the Northern Hemisphere it is winter.

Thus, due to the rotation of the Earth around the Sun, as well as due to the tilt of the Earth’s axis, our planet changes Seasons. In addition, different parts of the Earth receive different amounts of heat from the Sun, this determines the existence of thermal belts: hot tropical, temperate and cold polar.

The earth has the invisible magnetic field. The presence of this field causes the compass needle always point north. The earth has the only natural satellite - Moon(at a distance of 384,400 km from Earth). The moon revolves around the Earth. It reflects sunlight, so it seems to us that it glows.

From the attraction of the Moon on Earth there are ebb and flow. They are especially noticeable along the open ocean coast. The lunar gravity is so strong that the surface of the ocean arches towards our satellite. The moon moves around the Earth and follows it across the ocean tidal wave. When it reaches the shore, the tide occurs. After some time, the water moves away from the shore following the Moon.

Table "Earth - planet of the solar system."

The endless space that surrounds us is not just a huge airless space and emptiness. Here everything is subject to a single and strict order, everything has its own rules and obeys the laws of physics. Everything is in constant motion and is constantly interconnected with each other. This is a system in which each celestial body occupies its specific place. The center of the Universe is surrounded by galaxies, among which is our Milky Way. Our galaxy, in turn, is formed by stars around which large and small planets with their natural satellites revolve. The picture of a universal scale is complemented by wandering objects - comets and asteroids.

In this endless cluster of stars our Solar System is located - a tiny astrophysical object by cosmic standards, which includes our cosmic home - planet Earth. For us earthlings, the size of the solar system is colossal and difficult to perceive. In terms of the scale of the Universe, these are tiny numbers - only 180 astronomical units or 2.693e+10 km. Here, too, everything is subject to its own laws, has its own clearly defined place and sequence.

Brief characteristics and description

The interstellar medium and the stability of the Solar System are ensured by the location of the Sun. Its location is an interstellar cloud included in the Orion-Cygnus arm, which in turn is part of our galaxy. From a scientific point of view, our Sun is located on the periphery, 25 thousand light years from the center of the Milky Way, if we consider the galaxy in the diametrical plane. In turn, the movement of the solar system around the center of our galaxy is carried out in orbit. A complete revolution of the Sun around the center of the Milky Way is carried out in different ways, within 225-250 million years and is one galactic year. The orbit of the Solar System has an inclination of 600 to the galactic plane. Nearby, in the neighborhood of our system, other stars and other solar systems with their large and small planets are running around the center of the galaxy.

The approximate age of the Solar System is 4.5 billion years. Like most objects in the Universe, our star was formed as a result big bang. The origin of the solar system is explained by the action of the same laws that acted and continue to operate today in the region nuclear physics, thermodynamics and mechanics. First, a star was formed, around which, due to the ongoing centripetal and centrifugal processes, the formation of planets began. The Sun was formed from a dense accumulation of gases - a molecular cloud, which was the product of a colossal Explosion. As a result of centripetal processes, molecules of hydrogen, helium, oxygen, carbon, nitrogen and other elements were compressed into one continuous and dense mass.

The result of grandiose and such large-scale processes was the formation of a protostar, in the structure of which thermonuclear fusion began. We observe this long process, which began much earlier, today, looking at our Sun 4.5 billion years after its formation. The scale of the processes occurring during the formation of a star can be imagined by assessing the density, size and mass of our Sun:

• density is 1.409 g/cm3;
• the volume of the Sun is almost the same figure - 1.40927x1027 m3;
• star mass – 1.9885x1030 kg.

Today our Sun is an ordinary astrophysical object in the Universe, not the smallest star in our galaxy, but far from the largest. The Sun is in its mature age, being not only the center of the solar system, but also the main factor in the emergence and existence of life on our planet.

The final structure of the solar system falls on the same period, with a difference of plus or minus half a billion years. The mass of the entire system, where the Sun interacts with other celestial bodies of the Solar System, is 1.0014 M☉. In other words, all the planets, satellites and asteroids, cosmic dust and particles of gases revolving around the Sun, compared to the mass of our star, are a drop in the bucket.

The way we have an idea of ​​our star and the planets revolving around the Sun is a simplified version. For the first time, a mechanical heliocentric model of the solar system with a clock mechanism was presented scientific community in 1704. It should be taken into account that the orbits of the planets of the solar system do not all lie in the same plane. They rotate around at a certain angle.

The model of the solar system was created on the basis of a simpler and more ancient mechanism - tellurium, with the help of which the position and movement of the Earth in relation to the Sun was simulated. With the help of tellurium, it was possible to explain the principle of the movement of our planet around the Sun and to calculate the duration of the earth's year.

The simplest model of the solar system is presented in school textbooks, where each of the planets and other celestial bodies occupies a certain place. It should be taken into account that the orbits of all objects revolving around the Sun are located at different angles to the central plane of the Solar System. The planets of the Solar System are located at different distances from the Sun, rotate at different speeds and rotate differently around their own axis.

A map - a diagram of the Solar System - is a drawing where all objects are located in the same plane. In this case, such an image gives an idea only of the sizes of celestial bodies and the distances between them. Thanks to this interpretation, it became possible to understand the location of our planet among other planets, to assess the scale of celestial bodies and to give an idea of ​​the enormous distances that separate us from our celestial neighbors.

Planets and other objects of the solar system

Almost the entire universe is made up of myriads of stars, among which there are large and small solar systems. The presence of a star with its own satellite planets is a common occurrence in space. The laws of physics are the same everywhere and our solar system is no exception.

If you ask the question how many planets there were in the solar system and how many there are today, it is quite difficult to answer unequivocally. Currently, the exact location of 8 major planets is known. In addition, 5 small dwarf planets revolve around the Sun. The existence of a ninth planet is currently disputed in scientific circles.

The entire solar system is divided into groups of planets, which are arranged in the following order:

Terrestrial planets:

• Mercury;
• Venus;
• Mars.

Gas planets - giants:

• Jupiter;
• Saturn;
• Uranus;
• Neptune.

All planets presented in the list differ in structure and have different astrophysical parameters. Which planet is larger or smaller than the others? The sizes of the planets of the solar system are different. The first four objects, similar in structure to the Earth, have a solid rock surface and are endowed with an atmosphere. Mercury, Venus and Earth are the inner planets. Mars closes this group. Following it are the gas giants: Jupiter, Saturn, Uranus and Neptune - dense, spherical gas formations.

The process of life of the planets of the solar system does not stop for a second. Those planets that we see in the sky today are the arrangement of celestial bodies that the planetary system of our star has at the current moment. The state that existed at the dawn of the formation of the solar system is strikingly different from what has been studied today.

The astrophysical parameters of modern planets are indicated by the table, which also shows the distance of the planets of the Solar System to the Sun.

The existing planets of the solar system are approximately the same age, but there are theories that in the beginning there were more planets. This is evidenced by numerous ancient myths and legends that describe the presence of other astrophysical objects and disasters that led to the death of the planet. This is confirmed by the structure of our star system, where, along with planets, there are objects that are products of violent cosmic cataclysms.

A striking example of such activity is the asteroid belt, located between the orbits of Mars and Jupiter. Objects of extraterrestrial origin are concentrated here in huge numbers, mainly represented by asteroids and small planets. It is these fragments irregular shape in human culture they are considered the remains of the protoplanet Phaethon, which died billions of years ago as a result of a large-scale cataclysm.

In fact, there is an opinion in scientific circles that the asteroid belt was formed as a result of the destruction of a comet. Astronomers have discovered the presence of water on the large asteroid Themis and on the small planets Ceres and Vesta, which are the largest objects in the asteroid belt. Ice found on the surface of asteroids may indicate the cometary nature of the formation of these cosmic bodies.

Previously one of the major planets, Pluto is not considered a full-fledged planet today.

Pluto, which was previously ranked among the large planets of the solar system, is today reduced to the size of dwarf celestial bodies revolving around the Sun. Pluto, along with Haumea and Makemake, the largest dwarf planets, is located in the Kuiper belt.

These dwarf planets of the solar system are located in the Kuiper belt. The region between the Kuiper belt and the Oort cloud is the most distant from the Sun, but space is not empty there either. In 2005, the most distant celestial body of our solar system, the dwarf planet Eris, was discovered there. The process of exploration of the most distant regions of our solar system continues. The Kuiper Belt and Oort Cloud are hypothetically the border regions of our star system, the visible boundary. This cloud of gas is one light years from the Sun and is the region where comets, the wandering satellites of our star, are born.

Characteristics of the planets of the solar system

The terrestrial group of planets is represented by the planets closest to the Sun - Mercury and Venus. These two cosmic bodies of the solar system, despite the similarity in physical structure with our planet, are a hostile environment for us. Mercury is the smallest planet in our star system and is closest to the Sun. The heat of our star literally incinerates the surface of the planet, practically destroying its atmosphere. The distance from the surface of the planet to the Sun is 57,910,000 km. In size, only 5 thousand km in diameter, Mercury is inferior to most large satellites, which are dominated by Jupiter and Saturn.

Saturn's satellite Titan has a diameter of over 5 thousand km, Jupiter's satellite Ganymede has a diameter of 5265 km. Both satellites are second in size only to Mars.

The very first planet rushes around our star at tremendous speed, making a full revolution around our star in 88 Earth days. It is almost impossible to notice this small and nimble planet in the starry sky due to the close presence of the solar disk. Among the terrestrial planets, it is on Mercury that the largest daily temperature differences are observed. While the surface of the planet facing the Sun heats up to 700 degrees Celsius, back side The planet is immersed in universal cold with temperatures down to -200 degrees.

The main difference between Mercury and all the planets in the solar system is its internal structure. Mercury has the largest iron-nickel inner core, which accounts for 83% of the mass of the entire planet. However, even this uncharacteristic quality did not allow Mercury to have its own natural satellites.

Next to Mercury is the closest planet to us - Venus. The distance from Earth to Venus is 38 million km, and it is very similar to our Earth. The planet has almost the same diameter and mass, slightly inferior in these parameters to our planet. However, in all other respects, our neighbor is fundamentally different from our cosmic home. The period of Venus' revolution around the Sun is 116 Earth days, and the planet rotates extremely slowly around its own axis. The average surface temperature of Venus rotating around its axis over 224 Earth days is 447 degrees Celsius.

Like its predecessor, Venus lacks the physical conditions conducive to the existence of known life forms. The planet is surrounded by a dense atmosphere consisting mainly of carbon dioxide and nitrogen. Both Mercury and Venus are the only planets in the solar system that do not have natural satellites.

Earth is the last of inner planets Solar system, located from the Sun at a distance of approximately 150 million km. Our planet makes one revolution around the Sun every 365 days. Rotates around its own axis in 23.94 hours. The Earth is the first of the celestial bodies located on the path from the Sun to the periphery, which has a natural satellite.

Digression: The astrophysical parameters of our planet are well studied and known. Earth is the largest and densest planet of all the other inner planets in the solar system. It is here that natural physical conditions have been preserved under which the existence of water is possible. Our planet has a stable magnetic field that holds the atmosphere. Earth is the most well studied planet. The subsequent study is mainly of not only theoretical interest, but also practical one.

Mars closes the parade of terrestrial planets. The subsequent study of this planet is mainly not only of theoretical interest, but also of practical interest, associated with human exploration of extraterrestrial worlds. Astrophysicists are attracted not only by the relative proximity of this planet to Earth (on average 225 million km), but also by the absence of complex climatic conditions. The planet is surrounded by an atmosphere, although it is in an extremely rarefied state, has its own magnetic field, and temperature differences on the surface of Mars are not as critical as on Mercury and Venus.

Like the Earth, Mars has two satellites - Phobos and Deimos, the natural nature of which is Lately is in doubt. Mars is the last fourth planet with a rocky surface in the solar system. Following the asteroid belt, which is a kind of inner boundary of the solar system, begins the kingdom of gas giants.

The largest cosmic celestial bodies of our solar system

The second group of planets that are part of the system of our star has bright and large representatives. These are the largest objects in our solar system, which are considered the outer planets. Jupiter, Saturn, Uranus and Neptune are the most distant from our star, huge by earthly standards and their astrophysical parameters. These celestial bodies are distinguished by their massiveness and composition, which is mainly gaseous in nature.

The main beauties of the solar system are Jupiter and Saturn. The total mass of this pair of giants would be quite enough to fit in it the mass of all known celestial bodies of the Solar System. So Jupiter is the most big planet The solar system weighs 1876.64328 1024 kg, and the mass of Saturn is 561.80376 1024 kg. These planets have the most natural satellites. Some of them, Titan, Ganymede, Callisto and Io, are the largest satellites of the Solar System and are comparable in size to the terrestrial planets.

The largest planet in the solar system, Jupiter, has a diameter of 140 thousand km. In many respects, Jupiter more closely resembles a failed star - a striking example of the existence of a small solar system. This is evidenced by the size of the planet and astrophysical parameters - Jupiter is only 10 times smaller than our star. The planet rotates around its own axis quite quickly - only 10 Earth hours. The number of satellites, of which 67 have been identified to date, is also striking. The behavior of Jupiter and its moons is very similar to the model of the solar system. Such a number of natural satellites for one planet puts new question, how many planets there were in the solar system at the early stage of its formation. It is assumed that Jupiter, having a powerful magnetic field, turned some planets into its natural satellites. Some of them - Titan, Ganymede, Callisto and Io - are the largest satellites of the solar system and are comparable in size to the terrestrial planets.

Slightly smaller in size than Jupiter is its smaller brother, the gas giant Saturn. This planet, like Jupiter, consists mainly of hydrogen and helium - gases that are the basis of our star. With its size, the diameter of the planet is 57 thousand km, Saturn also resembles a protostar that has stopped in its development. The number of satellites of Saturn is slightly inferior to the number of satellites of Jupiter - 62 versus 67. Saturn's satellite Titan, like Io, a satellite of Jupiter, has an atmosphere.

In other words, the largest planets Jupiter and Saturn with their systems of natural satellites strongly resemble small solar systems, with their clearly defined center and system of movement of celestial bodies.

Behind the two gas giants come the cold and dark worlds, the planets Uranus and Neptune. These celestial bodies are located at a distance of 2.8 billion km and 4.49 billion km. from the Sun, respectively. Due to their enormous distance from our planet, Uranus and Neptune were discovered relatively recently. Unlike the other two gas giants, Uranus and Neptune contain large quantities of frozen gases - hydrogen, ammonia and methane. These two planets are also called ice giants. Uranus is smaller in size than Jupiter and Saturn and ranks third in the solar system. The planet represents the pole of cold of our star system. The average temperature on the surface of Uranus is -224 degrees Celsius. Uranus differs from other celestial bodies revolving around the Sun by its strong tilt on its own axis. The planet seems to be rolling, revolving around our star.

Like Saturn, Uranus is surrounded by a hydrogen-helium atmosphere. Neptune, unlike Uranus, has a different composition. The presence of methane in the atmosphere is indicated by the blue color of the planet's spectrum.

Both planets move slowly and majestically around our star. Uranus orbits the Sun in 84 Earth years, and Neptune orbits our star twice as long - 164 Earth years.

Finally

Our Solar System is a huge mechanism in which each planet, all satellites of the Solar System, asteroids and other celestial bodies move along a clearly defined route. The laws of astrophysics apply here and have not changed for 4.5 billion years. Along the outer edges of our solar system, dwarf planets move in the Kuiper belt. Comets are frequent guests of our star system. These space objects With a periodicity of 20-150 years, they visit the inner regions of the Solar System, flying within visibility range of our planet.

If you have any questions, leave them in the comments below the article. We or our visitors will be happy to answer them

The solar system is a group of planets revolving in specific orbits around a bright star - the Sun. This star is the main source of heat and light in the solar system.

It is believed that our planetary system was formed as a result of the explosion of one or more stars and this happened about 4.5 billion years ago. At first, the Solar System was an accumulation of gas and dust particles, however, over time and under the influence of its own mass, the Sun and other planets arose.

Planets of the Solar System

At the center of the solar system is the Sun, around which eight planets move in their orbits: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Until 2006, Pluto also belonged to this group of planets; it was considered the 9th planet from the Sun, however, due to its significant distance from the Sun and small size, it was excluded from this list and called a dwarf planet. More precisely, it is one of several dwarf planets in the Kuiper belt.

All of the above planets are usually divided into two large groups: the terrestrial group and the gas giants.

The terrestrial group includes such planets as: Mercury, Venus, Earth, Mars. They are distinguished by their small size and rocky surface, and in addition, they are located closest to the Sun.

Gas giants include: Jupiter, Saturn, Uranus, Neptune. They are characterized by large sizes and the presence of rings, which are ice dust and rocky pieces. These planets consist mainly of gas.

Mercury

This planet is one of the smallest in the solar system, its diameter is 4,879 km. In addition, it is closest to the Sun. This proximity predetermined a significant temperature difference. The average temperature on Mercury during the day is +350 degrees Celsius, and at night - -170 degrees.

1. Mercury is the first planet from the Sun.
2. There are no seasons on Mercury. The tilt of the planet's axis is almost perpendicular to the plane of the planet's orbit around the Sun.
3. The temperature on the surface of Mercury is not the highest, although the planet is located closest to the Sun. He lost first place to Venus.
4. The first research vehicle to visit Mercury was Mariner 10. It conducted a number of demonstration flights in 1974.
5. A day on Mercury lasts 59 Earth days, and a year is only 88 days.
6. Mercury experiences the most dramatic temperature changes, reaching 610 °C. During the day, temperatures can reach 430 °C, and at night -180 °C.
7. The gravity on the planet's surface is only 38% of Earth's. This means that on Mercury you could jump three times as high, and it would be easier to lift heavy objects.
8. The first observations of Mercury through a telescope were made by Galileo Galilei in the early 17th century.
9. Mercury has no natural satellites.
10. The first official map of Mercury's surface was published only in 2009, thanks to data obtained from the Mariner 10 and Messenger spacecraft.

Venus

This planet is the second from the Sun. In size it is close to the diameter of the Earth, the diameter is 12,104 km. In all other respects, Venus differs significantly from our planet. A day here lasts 243 Earth days, and a year lasts 255 days. The atmosphere of Venus is 95% composed of carbon dioxide, which creates on its surface Greenhouse effect. This results in an average temperature on the planet of 475 degrees Celsius. The atmosphere also contains 5% nitrogen and 0.1% oxygen.

1. Venus is the second planet from the Sun in the Solar System.
2. Venus is the hottest planet in the solar system, although it is the second planet from the sun. Surface temperature can reach 475 °C.
   
3. The first spacecraft sent to explore Venus was sent from Earth on February 12, 1961 and was called Venera 1.
4. Venus is one of two planets whose direction of rotation around its axis is different from most planets in the solar system.
5. The planet's orbit around the Sun is very close to circular.
6. The day and night temperatures of the surface of Venus are practically the same due to the large thermal inertia of the atmosphere.
7. Venus makes one revolution around the Sun in 225 Earth days, and one revolution around its axis in 243 Earth days, that is, one day on Venus lasts more than one year.
8. The first observations of Venus through a telescope were made by Galileo Galilei at the beginning of the 17th century.
9. Venus has no natural satellites.
10. Venus is the third brightest object in the sky, after the Sun and Moon.

Earth

Our planet is located at a distance of 150 million km from the Sun, and this allows us to create on its surface a temperature suitable for the existence of liquid water, and, therefore, for the emergence of life.

Its surface is 70% covered with water, and it is the only planet to contain such an amount of liquid. It is believed that many thousands of years ago, steam contained in the atmosphere created the temperature on the Earth's surface necessary for the formation of water in liquid form, and solar radiation contributed to photosynthesis and the birth of life on the planet.

1. Earth in the solar system is the third planet from the sunsA;
2. Our planet revolves around one natural satellite - the Moon;
   
3. Earth is the only planet not named after a divine being;
4. The Earth's density is the greatest of all the planets in the solar system;
5. The Earth's rotation speed is gradually slowing down;
6. The average distance from the Earth to the Sun is 1 astronomical unit (a conventional measure of length in astronomy), which is approximately 150 million km;
7. The Earth has a magnetic field of sufficient strength to protect living organisms on its surface from harmful solar radiation;
8. The first artificial Earth satellite, called PS-1 (The simplest satellite - 1), was launched from the Baikonur Cosmodrome on the Sputnik launch vehicle on October 4, 1957;
9. In orbit around the Earth, compared to other planets, there is the largest number of spacecraft;
10. The earth is the most big planet terrestrial group in the solar system;

Mars

This planet is the fourth from the Sun and is 1.5 times more distant from it than the Earth. The diameter of Mars is smaller than Earth's and is 6,779 km. The average air temperature on the planet ranges from -155 degrees to +20 degrees at the equator. The magnetic field on Mars is much weaker than that of Earth, and the atmosphere is quite thin, which allows solar radiation to unimpededly affect the surface. In this regard, if there is life on Mars, it is not on the surface.

When surveyed with the help of Mars rovers, it was found that there are many mountains on Mars, as well as dried up river beds and glaciers. The surface of the planet is covered with red sand. It is iron oxide that gives Mars its color.

1. Mars is located in the fourth orbit from the Sun;
2. The Red Planet is home to the tallest volcano in the solar system;
   
3. Of the 40 exploration missions sent to Mars, only 18 were successful;
4. Mars is home to some of the largest dust storms in the solar system;
5. In 30-50 million years, a system of rings will be located around Mars, like Saturn;
6. Debris from Mars has been found on Earth;
7. The Sun from the surface of Mars looks half as big as from the surface of the Earth;
   
8. Mars is the only planet in the solar system that has polar ice caps;
9. Two natural satellites revolve around Mars - Deimos and Phobos;
10. Mars has no magnetic field;

Jupiter

This planet is the largest in the solar system and has a diameter of 139,822 km, which is 19 times larger than Earth. A day on Jupiter lasts 10 hours, and a year is approximately 12 Earth years. Jupiter is mainly composed of xenon, argon and krypton. If it were 60 times larger, it could become a star due to a spontaneous thermonuclear reaction.

The average temperature on the planet is -150 degrees Celsius. The atmosphere consists of hydrogen and helium. There is no oxygen or water on its surface. There is an assumption that there is ice in the atmosphere of Jupiter.

1. Jupiter is located in the fifth orbit from the Sun;
2. In the Earth's sky, Jupiter is the fourth brightest object, after the Sun, Moon and Venus;
   
3. Jupiter has the shortest day of all the planets in the solar system;
4. In the atmosphere of Jupiter, one of the longest and most powerful storms in the solar system rages, better known as the Great Red Spot;
5. Jupiter's moon, Ganymede, is the most big moon in the solar system;
6. Jupiter is surrounded by a thin system of rings;
7. Jupiter was visited by 8 research vehicles;
   
8. Jupiter has a strong magnetic field;
   
9. If Jupiter were 80 times more massive, it would become a star;
10. There are 67 natural satellites orbiting Jupiter. This is the largest in the Solar System;

Saturn

This planet is the second largest in the solar system. Its diameter is 116,464 km. It is most similar in composition to the Sun. A year on this planet lasts quite a long time, almost 30 Earth years, and a day lasts 10.5 hours. The average surface temperature is -180 degrees.

Its atmosphere consists mainly of hydrogen and a small amount of helium. Thunderstorms and auroras often occur in its upper layers.

1. Saturn is the sixth planet from the Sun;
2. Saturn's atmosphere contains the strongest winds in the solar system;
   
3. Saturn is one of the least dense planets in the solar system;
   
4. Surrounding the planet is the largest ring system in the Solar System;
5. One day on the planet lasts almost one Earth year and is equal to 378 Earth days;
6. Saturn was visited by 4 research spacecraft;
7. Saturn, together with Jupiter, constitutes approximately 92% of the total planetary mass of the Solar System;
8. One year on the planet lasts 29.5 Earth years;
9. There are 62 known natural satellites orbiting the planet;
10. Currently, the automatic interplanetary station Cassini is studying Saturn and its rings;

Uranus

Uranus, computer artwork.

Uranus is the third largest planet in the solar system and the seventh from the Sun. It has a diameter of 50,724 km. It is also called the “ice planet”, as the temperature on its surface is -224 degrees. A day on Uranus lasts 17 hours, and a year lasts 84 Earth years. Moreover, summer lasts as long as winter - 42 years. This natural phenomenon is due to the fact that the axis of that planet is located at an angle of 90 degrees to the orbit and it turns out that Uranus seems to be “lying on its side.”

1. Uranus is located in the seventh orbit from the Sun;
2. The first person to learn about the existence of Uranus was William Herschel in 1781;
   
3. Uranus has only been visited by one spacecraft, Voyager 2 in 1982;
4. Uranus is the coldest planet in the solar system;
5. The plane of Uranus' equator is inclined to the plane of its orbit at almost a right angle - that is, the planet rotates retrograde, "lying on its side slightly upside down";
6. The moons of Uranus bear names taken from the works of William Shakespeare and Alexander Pope, rather than Greek or Roman mythology;
7. A day on Uranus lasts about 17 Earth hours;
8. There are 13 known rings around Uranus;
9. One year on Uranus lasts 84 Earth years;
10. There are 27 known natural satellites orbiting Uranus;

Neptune

Neptune is the eighth planet from the Sun. It is similar in composition and size to its neighbor Uranus. The diameter of this planet is 49,244 km. A day on Neptune lasts 16 hours, and a year is equal to 164 Earth years. Neptune is an ice giant and for a long time it was believed that no weather phenomena occur on its icy surface. However, it was recently discovered that Neptune has raging vortices and wind speeds that are the highest among the planets in the solar system. It reaches 700 km/h.

Neptune has 14 moons, the most famous of which is Triton. It is known to have its own atmosphere.

Neptune also has rings. This planet has 6 of them.

1. Neptune is the most distant planet in the Solar System and occupies the eighth orbit from the Sun;
2. Mathematicians were the first to know about the existence of Neptune;
   
3. There are 14 satellites circling around Neptune;
4. Neputna's orbit is removed from the Sun by an average of 30 AU;
5. One day on Neptune lasts 16 Earth hours;
6. Neptune has only been visited by one spacecraft, Voyager 2;
7. There is a system of rings around Neptune;
8. Neptune has the second highest gravity after Jupiter;
9. One year on Neptune lasts 164 Earth years;
10. The atmosphere on Neptune is extremely active;

1. Jupiter is considered the largest planet in the solar system.
2. There are 5 dwarf planets in the Solar System, one of which has been reclassified as Pluto.
3. There are very few asteroids in the Solar System.
4. Venus is the hottest planet in the solar system.
5. About 99% of the space (by volume) is occupied by the Sun in the Solar System.
6. The satellite of Saturn is considered one of the most beautiful and original places in the solar system. There you can see a huge concentration of ethane and liquid methane.
7. Our solar system has a tail that resembles a four-leaf clover.
8. The sun follows a continuous 11-year cycle.
9. There are 8 planets in the solar system.
10. The Solar System is fully formed thanks to a large gas and dust cloud.
11. Spacecraft have flown to all the planets of the solar system.
12. Venus is the only planet in the solar system that rotates counterclockwise around its axis.
13. Uranus has 27 satellites.
14. The largest mountain is on Mars.
15. A huge mass of objects in the solar system fell on the sun.
16. The solar system is part of the Milky Way galaxy.
17. The sun is the central object of the solar system.
18. The solar system is often divided into regions.
19. The Sun is a key component of the Solar System.
20. The solar system was formed approximately 4.5 billion years ago.
21. The most distant planet in the solar system is Pluto.
22. Two regions in the Solar System are filled with small bodies.
23. The solar system was built contrary to all the laws of the Universe.
24. If you compare the solar system and space, then it is just a grain of sand in it.
25. Over the past few centuries, the solar system has lost 2 planets: Vulcan and Pluto.
26. Researchers claim that the solar system was created artificially.
27. The only satellite of the Solar System that has a dense atmosphere and whose surface cannot be seen due to cloud cover is Titan.
28. The region of the solar system that lies beyond the orbit of Neptune is called the Kuiper belt.
29. The Oort cloud is the region of the solar system that serves as the source of a comet and a long orbital period.
30. Every object in the solar system is held there because of the force of gravity.
31. The leading theory of the solar system involves the emergence of planets and moons from a huge cloud.
32. The solar system is considered the most secret particle of the Universe.
33. There is a huge asteroid belt in the solar system.
34. On Mars you can see the eruption of the largest volcano in the solar system, which is called Olympus.
35. Pluto is considered to be the outskirts of the solar system.
36. Jupiter has a large ocean of liquid water.
37. The Moon is the largest satellite of the Solar System.
38. Pallas is considered the largest asteroid in the solar system.
39. The brightest planet in the solar system is Venus.
40. The solar system is mostly made of hydrogen.
41. The Earth is an equal member of the solar system.
42. The sun heats up slowly.
43. Oddly enough, the most huge reserves There is water in the solar system in the sun.
44. The equator plane of each planet in the solar system diverges from the orbital plane.
45. The satellite of Mars called Phobos is an anomaly in the solar system.
46. The solar system can amaze with its diversity and scale.
47. The planets of the solar system are influenced by the sun.
48. The outer shell of the Solar System is considered to be the haven of satellites and gas giants.
49. A huge number of planetary satellites of the solar system are dead.
50. The largest asteroid, with a diameter of 950 km, is called Ceres.

Not so long ago, any educated person, when asked how many planets are in the solar system, would have answered without hesitation - nine. And he would be right. If you don’t particularly follow events in the world of astronomy and are not a regular viewer of the Discovery Channel, then today you will answer the same question. However, this time you will be wrong.

And here's the thing. In 2006, namely, on August 26, 2.5 thousand participants in the congress of the International Astronomical Union made a sensational decision and actually deleted Pluto from the list of planets of the solar system, since 76 years after its discovery it ceased to meet the requirements set by scientists for planets.

Let's first figure out what a planet is, and also how many planets in the solar system astronomers have left for us, and consider each of them separately.

A little history

Previously, a planet was considered to be any body that orbits a star, glows with light reflected from it, and is larger than an asteroid.

Even in Ancient Greece, they mentioned seven luminous bodies that move across the sky against the backdrop of fixed stars. These cosmic bodies were: the Sun, Mercury, Venus, Moon, Mars, Jupiter and Saturn. The earth was not included in this list, since the ancient Greeks considered the earth to be the center of all things. And only in the 16th century, Nicolaus Copernicus, in his scientific work entitled “On the Revolution of the Celestial Spheres,” came to the conclusion that it was not the Earth, but the Sun that should be at the center of the planetary system. Therefore, the Sun and Moon were removed from the list, and the Earth was added to it. And after the advent of telescopes, Uranus and Neptune were added, in 1781 and 1846, respectively.
Last open planet The solar system from 1930 until recently was considered Pluto.

And now, almost 400 years after Galileo Galilei created the world's first telescope for observing stars, astronomers have come to the following definition of a planet.

Planet is a celestial body that must satisfy four conditions:
the body must revolve around a star (for example, around the Sun);
the body must have sufficient gravity to have a spherical or close to it shape;
the body should not have other large bodies near its orbit;

The body does not have to be a star.

In its turn star is a cosmic body that emits light and is a powerful source of energy. This is explained, firstly, by the thermonuclear reactions occurring in it, and secondly, by the processes of gravitational compression, as a result of which a huge amount of energy is released.

Planets of the Solar System today

solar system is a planetary system that consists of a central star - the Sun - and all natural space objects, revolving around it.

So, today the solar system consists of eight planets: four inner, so-called terrestrial planets, and four outer planets, called gas giants.
The terrestrial planets include Earth, Mercury, Venus and Mars. All of them consist mainly of silicates and metals.

The outer planets are Jupiter, Saturn, Uranus and Neptune. Gas giants are composed mainly of hydrogen and helium.

The sizes of the planets of the Solar System vary both within groups and between groups. Thus, gas giants are much larger and more massive than terrestrial planets.
Mercury is closest to the Sun, then as it moves away: Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

It would be wrong to consider the characteristics of the planets of the Solar System without paying attention to its main component: the Sun itself. Therefore, we will start with it.

Sun

The Sun is the star that gave rise to all life in the Solar System. Planets, dwarf planets and their satellites, asteroids, comets, meteorites and cosmic dust revolve around it.

The Sun arose about 5 billion years ago, is a spherical, hot plasma ball and has a mass that is more than 300 thousand times the mass of the Earth. The surface temperature is more than 5000 degrees Kelvin, and the core temperature is more than 13 million K.

The Sun is one of the largest and brightest stars in our galaxy, which is called the Milky Way galaxy. The Sun is located at a distance of about 26 thousand light years from the center of the Galaxy and makes a full revolution around it in about 230-250 million years! For comparison, the Earth makes a full revolution around the Sun in 1 year.

Mercury

Mercury is the smallest planet in the system, which is closest to the Sun. Mercury has no satellites.

The surface of the planet is covered with craters that appeared about 3.5 billion years ago as a result of massive bombardment by meteorites. The diameter of the craters can range from a few meters to more than 1000 km.

The atmosphere of Mercury is very thin, consists mainly of helium and is inflated by the solar wind. Since the planet is located very close to the Sun and does not have an atmosphere that would retain heat at night, the surface temperature ranges from -180 to +440 degrees Celsius.

By earthly standards, Mercury completes a full revolution around the Sun in 88 days. But a Mercury day is equal to 176 Earth days.

Venus

Venus is the second planet closest to the Sun in the solar system. Venus is only slightly smaller in size than Earth, which is why it is sometimes called “Earth’s sister.” Has no satellites.

The atmosphere consists of carbon dioxide mixed with nitrogen and oxygen. The air pressure on the planet is more than 90 atmospheres, which is 35 times more than on Earth.

Carbon dioxide and the resulting greenhouse effect, dense atmosphere, and proximity to the Sun allow Venus to bear the title of “hottest planet.” The temperature on its surface can reach 460°C.

Venus is one of the brightest objects in the earth's sky after the Sun and Moon.

Earth

Earth is the only planet known today in the Universe on which there is life. The Earth has the largest size, mass and density among the so-called inner planets of the Solar System.

The age of the Earth is about 4.5 billion years, and life appeared on the planet about 3.5 billion years ago. The Moon is a natural satellite, the largest of the satellites of the terrestrial planets.

The Earth's atmosphere is fundamentally different from the atmospheres of other planets due to the presence of life. Most of the atmosphere consists of nitrogen, but also includes oxygen, argon, carbon dioxide and water vapor. The ozone layer and the Earth's magnetic field, in turn, weaken the life-threatening influence of solar and cosmic radiation.

Due to the carbon dioxide contained in the atmosphere, the greenhouse effect also occurs on Earth. It is not as pronounced as on Venus, but without it the air temperature would be about 40°C lower. Without an atmosphere, temperature fluctuations would be very significant: according to scientists, from -100°C at night to +160°C during the day.

About 71% of the Earth's surface is occupied by the world's oceans, the remaining 29% are continents and islands.

Mars

Mars is the seventh largest planet in the solar system. “Red Planet”, as it is also called due to the presence of large amounts of iron oxide in the soil. Mars has two satellites: Deimos and Phobos.
The atmosphere of Mars is very thin, and the distance to the Sun is almost one and a half times greater than that of the Earth. Therefore, the average annual temperature on the planet is -60°C, and temperature changes in some places reach 40 degrees during the day.

Distinctive features of the surface of Mars are impact craters and volcanoes, valleys and deserts, and polar ice caps similar to those on Earth. Mars has the most high mountain in the solar system: the extinct volcano Olympus, whose height is 27 km! And also the largest canyon: Valles Marineris, whose depth reaches 11 km and length – 4500 km.

Jupiter

Jupiter is the largest planet in the solar system. It is 318 times heavier than the Earth, and almost 2.5 times more massive than all the planets in our system combined. In its composition, Jupiter resembles the Sun - it consists mainly of helium and hydrogen - and emits a huge amount of heat equal to 4 * 1017 W. However, in order to become a star like the Sun, Jupiter must be 70-80 times heavier.

Jupiter has as many as 63 satellites, of which it makes sense to list only the largest - Callisto, Ganymede, Io and Europa. Ganymede is the largest moon in the solar system, even larger than Mercury.

Due to certain processes in the inner atmosphere of Jupiter, many vortex structures appear in its outer atmosphere, for example, bands of clouds in brown-red shades, as well as the Great Red Spot, a giant storm known since the 17th century.

Saturn

Saturn is the second largest planet in the solar system. Saturn's calling card is, of course, its ring system, which consists mainly of icy particles of various sizes (from tenths of a millimeter to several meters), as well as rocks and dust.

Saturn has 62 moons, the largest of which are Titan and Enceladus.
In its composition, Saturn resembles Jupiter, but in density it is inferior even to ordinary water.
The planet's outer atmosphere appears calm and uniform, which is explained by a very dense layer of fog. However, wind speeds in some places can reach 1800 km/h.

Uranus

Uranus is the first planet discovered by telescope, and the only planet in the Solar System that orbits the Sun on its side.
Uranus has 27 moons, which are named after Shakespearean heroes. The largest of them are Oberon, Titania and Umbriel.

The composition of the planet differs from gas giants in the presence of a large number of high-temperature modifications of ice. Therefore, along with Neptune, scientists have classified Uranus as an “ice giant.” And if Venus has the title of “hottest planet” in the solar system, then Uranus is the coldest planet with a minimum temperature of about -224°C.

Neptune

Neptune is the most distant planet in the solar system from the center. The story of its discovery is interesting: before observing the planet through a telescope, scientists used mathematical calculations to calculate its position in the sky. This happened after the discovery of inexplicable changes in the movement of Uranus in its own orbit.

Today, 13 satellites of Neptune are known to science. The largest of them, Triton, is the only satellite that moves in the direction opposite to the rotation of the planet. The fastest winds in the solar system also blow against the rotation of the planet: their speed reaches 2200 km/h.

In composition, Neptune is very similar to Uranus, therefore it is the second “ice giant”. However, like Jupiter and Saturn, Neptune has internal source heat and emits 2.5 times more energy than it receives from the Sun.
The blue color of the planet is given by traces of methane in the outer layers of the atmosphere.

Conclusion
Pluto, unfortunately, did not manage to get into our parade of planets in the solar system. But there is absolutely no need to worry about this, because all the planets remain in their places, despite changes in scientific views and concepts.

So, we answered the question how many planets are there in the solar system. There are only 8 .