The solar system includes the central star and all natural space objects revolving around it. It was formed by gravitational compression of a gas and dust cloud approximately 4.57 billion years ago. The solar system includes 8 * planets, of which half belong to the terrestrial group: these are Mercury, Venus, Earth and Mars. They are also called the inner planets, in contrast to the outer giant planets Jupiter, Saturn, Uranus and Neptune, located outside the ring of minor planets.

1. Mercury
The closest planet to the Sun in the solar system is named after the ancient Roman god of trade, swift-footed Mercury, as it moves through the celestial sphere faster than other planets.

2. Venus
The second planet in the solar system was named after the ancient Roman goddess of love, Venus. This is the brightest object in the earth's sky after the Sun and the Moon and the only planet in the solar system named after a female deity.

3. Earth
The third planet from the Sun and the fifth largest among all the planets in the solar system has had its current name since 1400, but who exactly named it that way is unknown. The English Earth originated from an 8th-century Anglo-Saxon word meaning earth or soil. This is the only planet in the solar system with a name that is not related to Roman mythology.

4. Mars
The seventh largest planet in the solar system has a reddish tint to its surface, imparted by iron oxide. With such a "bloody" association, the object was named after the ancient Roman god of war Mars.

5. Jupiter
The largest planet in the solar system is named after the ancient Roman supreme god of thunder. 6. Saturn Saturn is the slowest planet in the solar system, which is symbolically reflected in its first name: it was given in honor of the ancient Greek god of time Kronos. In Roman mythology, the god of agriculture Saturn turned out to be an analogue of Kronos, and as a result, this name was assigned to the planet.

7. Uranus
The third largest and fourth largest planet in the solar system was discovered in 1781 by the English astronomer William Herschel. The tradition of naming the planets was continued, and the international community named the new celestial body in honor of the father of Kronos, the Greek god of the sky, Uranus.

8. Neptune
Discovered on September 23, 1846, Neptune was the first planet discovered through mathematical calculations, and not through regular observations. The large blue giant (this color is due to the hue of the atmosphere) is named after the Roman god of the seas.

Pluto in 2006, it lost the status of a planet in the solar system and was classified as a dwarf planet and the largest object in the Kuiper belt. It has been in the status of the ninth planet of the solar system since its discovery in 1930. The name "Pluto" was first proposed by an eleven-year-old schoolgirl from Oxford, Venetia Burney. She was interested not only in astronomy, but also in classical mythology, and decided that this name - the ancient Roman version of the name of the Greek god of the underworld - was best suited for a dark, distant and cold world. Astronomers chose this option by voting.

Look at the model of the solar system created in the American desert.

* Recently scientists . Since it does not yet have a full name, and research is still ongoing, we did not include it in the above list..

Pluto By decision of the MAC (International Astronomical Union), it no longer belongs to the planets of the solar system, but is a dwarf planet and even inferior in diameter to the other dwarf planet Eris. Pluto's designation is 134340.

solar system

Scientists put forward many versions of the origin of our solar system. In the 40s of the last century, Otto Schmidt hypothesized that the solar system arose because cold dust clouds were attracted to the Sun. Over time, clouds formed the foundations of future planets. In modern science, it is Schmidt's theory that is the main one. The solar system is only a small part of a large galaxy called the Milky Way. The Milky Way contains over a hundred billion different stars. It took humanity thousands of years to realize such a simple truth. The discovery of the solar system did not happen immediately, step by step, on the basis of victories and mistakes, a system of knowledge was formed. The main basis for studying the solar system was knowledge about the Earth.

Fundamentals and Theories

The main milestones in the study of the solar system are the modern atomic system, the heliocentric system of Copernicus and Ptolemy. The most likely version of the origin of the system is the Big Bang theory. In accordance with it, the formation of the galaxy began with the "scattering" of the elements of the megasystem. At the turn of the impenetrable house, our solar system was born. The basis of everything is the Sun - 99.8% of the total volume, the planets account for 0.13%, the remaining 0.0003% are various bodies of our system. Scientists divide the planets into two conditional groups . The first includes planets of the Earth type: the Earth itself, Venus, Mercury. The main distinguishing characteristics of the planets of the first group are a relatively small area, hardness, and a small number of satellites. The second group includes Uranus, Neptune and Saturn - they are distinguished by their large size (giant planets), they are formed by helium and hydrogen gases.

In addition to the Sun and planets, our system also includes planetary satellites, comets, meteorites and asteroids.

Particular attention should be paid to the asteroid belts that are located between Jupiter and Mars, and between the orbits of Pluto and Neptune. At the moment, there is no unequivocal version of the emergence of such formations in science.
Which planet is not considered a planet now:

Pluto was considered a planet from the time of its discovery until 2006, but later in the outer part of the solar system many celestial bodies comparable in size to Pluto and even exceeding it were discovered. To avoid confusion, a new definition of the planet was given. Pluto did not fall under this definition, so it was assigned a new "status" - a dwarf planet. So, Pluto can serve as an answer to the question: before it was considered a planet, but now it is not. However, some scientists continue to believe that Pluto should be reclassified back into a planet.

Scientists' forecasts

Based on research, scientists say that the sun is approaching the middle of its life path. It is unimaginable to imagine what will happen if the Sun goes out. But scientists say it's not only possible, it's inevitable. The age of the Sun was determined using the latest computer developments and found out that it has about five billion years. According to astronomical law, the life of a star like the Sun lasts about ten billion years. Thus, our solar system is in the middle of the life cycle. What do scientists mean by the word "goes out"? The huge solar energy is the energy of hydrogen, which in the core becomes helium. Every second, about six hundred tons of hydrogen in the core of the Sun is converted into helium. According to scientists, the Sun has already used up most of its hydrogen reserves.

If instead of the Moon there were planets of the solar system:

The boundless 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 has its own 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 revolve with their natural satellites. Wandering objects - comets and asteroids - complete the picture of the universal scale.

Our solar system is also located in this endless cluster of stars - a tiny astrophysical object by cosmic standards, which also includes our cosmic home - the planet Earth. For us earthlings, the size of the solar system is colossal and difficult to comprehend. 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 description and description

The position of the Sun provides the interstellar medium and the stability of the solar system. Its location is an interstellar cloud that is part of 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. The full rotation 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 run 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 of the Big Bang. The origin of the solar system is explained by the action of the same laws that have operated and continue to operate today in the field of nuclear physics, thermodynamics and mechanics. First, a star was formed, around which, due to ongoing centripetal and centrifugal processes, the formation of planets began. The sun was formed from a dense collection of gases - a molecular cloud, which was the product of a colossal explosion. As a result of centripetal processes, the 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. This long process, which began much earlier, we observe today, looking at our Sun after 4.5 billion years from the moment of its formation. The scale of the processes occurring during the formation of a star can be represented by estimating the density, size and mass of our Sun:

• the density is 1.409 g/cm3;
• the volume of the Sun is almost the same figure - 1.40927x1027 m3;
• the mass of the star is 1.9885x1030kg.

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, in comparison with the mass of our star, are a drop in the ocean.

In the form in which we have an idea of ​​​​our star and planets revolving around the Sun - this is a simplified version. For the first time, a mechanical heliocentric model of the solar system with a clockwork was presented to the scientific community in 1704. It should be borne in mind 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 modeled. With the help of tellurium, it was possible to explain the principle of the movement of our planet around the Sun, 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 occupy a certain place. In this case, it should be taken into account that the orbits of all objects revolving around the Sun are located at different angles to the diametrical 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 around their own axis in different ways.

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 size of celestial bodies and the distances between them. Thanks to this interpretation, it became possible to understand the location of our planet in a number of other planets, to assess the scale of celestial bodies and to give an idea of ​​the vast distances that separate us from our celestial neighbors.

Planets and other objects of the solar system

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

If you ask yourself how many planets there were in the solar system and how many there are today, it is quite difficult to answer unambiguously. 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 the planets presented in the list differ in structure, 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 stone surface and are endowed with an atmosphere. Mercury, Venus and Earth are the inner planets. Mars closes this group. It is followed by 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 today in the sky are the arrangement of celestial bodies that the planetary system of our star has at the current moment. The state that was at the dawn of the formation of the solar system is strikingly different from what is studied today.

The table shows the astrophysical parameters of modern planets, which also indicates the distance of the planets of the solar system to the sun.

The existing planets of the solar system are about the same age, but there are theories that there were more planets in the beginning. This is evidenced by numerous ancient myths and legends describing the presence of other astrophysical objects and catastrophes that led to the death of the planet. This is confirmed by the structure of our star system, where, along with the 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. Here, objects of extraterrestrial origin are concentrated in a huge number, mainly represented by asteroids and small planets. It is these fragments of irregular shape in human culture that are considered the remains of the protoplanet Phaeton, 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 minor planets Ceres and Vesta, which are the largest objects in the asteroid belt. The ice found on the surface of asteroids may indicate the cometary nature of the formation of these cosmic bodies.

Previously, Pluto, belonging to the number of large planets, is not considered a full-fledged planet today.

Pluto, which was previously ranked among the large planets of the solar system, is now translated into the size of dwarf celestial bodies revolving around the sun. Pluto, along with Haumea and Makemake, the largest dwarf planets, is 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 even there space is not empty. In 2005, the most distant celestial body in our solar system, the dwarf planet Eridu, was discovered there. The process of exploring the most distant regions of our solar system continues. The Kuiper Belt and the Oort Cloud are hypothetically the boundary regions of our star system, the visible boundary. This cloud of gas is located at a distance of one light year from the Sun and is the area where comets, 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 the atmosphere on it. 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 of the large satellites that are dominated by Jupiter and Saturn.

Saturn's satellite Titan has a diameter of over 5,000 km, Jupiter's satellite Ganymede has a diameter of 5265 km. Both satellites are second only to Mars in size.

The very first planet rushes around our star at great speed, making a complete 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 drops are observed. While the surface of the planet, facing the Sun, is heated up to 700 degrees Celsius, the reverse side of the planet is immersed in universal cold with temperatures up to -200 degrees.

The main difference between Mercury and all the planets of 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 the 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 space home. The period of revolution of Venus around the Sun is 116 Earth days, and the planet rotates extremely slowly around its own axis. The average temperature of the surface of Venus rotating around its axis for 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.

The Earth is the last of the inner planets of the solar system, located at a distance of about 150 million km from the Sun. Our planet makes one revolution around the sun in 365 days. It rotates around its own axis in 23.94 hours. The Earth is the first of the celestial bodies, located on the way 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.

Closes the parade of planets of the terrestrial group Mars. The subsequent study of this planet is mainly not only of theoretical interest, but also of practical interest, connected with the development of extraterrestrial worlds by man. Astrophysicists are attracted not only by the relative proximity of this planet to the Earth (on average 225 million km), but also by the absence of difficult climatic conditions. The planet is surrounded by an atmosphere, although it is in an extremely rarefied state, it has its own magnetic field and temperature drops 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 has recently been questioned. Mars is the last fourth planet with a solid surface in the solar system. Following the asteroid belt, which is a kind of inner boundary of the solar system, the realm of gas giants begins.

The largest cosmic celestial bodies in our solar system

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

The main beauties of the solar system are Jupiter and Saturn. The total mass of this pair of giants would be enough to fit in it the mass of all known celestial bodies in the solar system. So Jupiter - the largest planet in 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 in 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 is more like a failed star - a vivid 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 pieces 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 raises a new question, how many planets of the solar system were at an early stage of its formation. It is assumed that Jupiter, having a powerful magnetic field, turned some of the 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 inferior in size to 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. On the satellite of Saturn, Titan, as well as on Io, the satellite of Jupiter, there is 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.

The two gas giants are followed by 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 great distance from our planet, Uranus and Neptune were discovered relatively recently. Unlike the other two gas giants, Uranus and Neptune have a large amount of frozen gases - hydrogen, ammonia and methane. These two planets are also called ice giants. Uranus is smaller than Jupiter and Saturn and is the third largest planet in the solar system. The planet represents the cold pole 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 a strong inclination of 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 spectrum of the planet.

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

Finally

Our solar system is a huge mechanism in which every planet, all the satellites of the solar system, asteroids and other celestial bodies move along a clearly defined route. The laws of astrophysics operate here, which have not changed for 4.5 billion years. Dwarf planets move along the outer edges of our solar system in the Kuiper belt. Comets are frequent guests of our star system. These space objects visit the inner regions of the solar system with a frequency of 20-150 years, flying in the visibility zone from 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.

solar system- this is a system of celestial bodies soldered by the forces of mutual attraction. It includes: the central star - the Sun, 8 large planets with their satellites, several thousand small planets, or asteroids, several hundred observed comets and countless meteoroids, dust, gas and small particles . It was formed through gravitational contraction gas and dust cloud approximately 4.57 billion years ago.

Sun

Merkur uy

Mercury is the closest planet to the Sun.

The ancient Romans considered Mercury the patron of trade, travelers and thieves, as well as the messenger of the gods. It is not surprising that a small planet, rapidly moving across the sky following the Sun, was named after him. Mercury has been known since ancient times, but the ancient astronomers did not immediately realize that they see the same star in the morning and in the evening. Mercury is closer to the Sun than the Earth: the average distance from the Sun is 0.387 AU, and the distance to the Earth varies from 82 to 217 million km. The inclination of the orbit to the ecliptic i = 7° is one of the largest in the solar system. The axis of Mercury is almost perpendicular to the plane of its orbit, and the orbit itself is very elongated (eccentricity e = 0.206). The average velocity of Mercury in orbit is 47.9 km/s. Due to the tidal influence of the Sun, Mercury fell into a resonant trap. The period of its revolution around the Sun (87.95 Earth days) measured in 1965 refers to the period of rotation around the axis (58.65 Earth days) as 3/2. Mercury completes three complete rotations around its axis in 176 days. During the same period, the planet makes two revolutions around the Sun. Thus, Mercury occupies the same position in orbit relative to the Sun, and the orientation of the planet remains the same. Mercury has no satellites. If they were, then in the process of the formation of the planet they fell on protomercury. The mass of Mercury is almost 20 times less than the mass of the Earth (0.055M or 3.3 10 23 kg), and the density is almost the same as that of the Earth (5.43 g/cm3). The radius of the planet is 0.38R (2440 km). Mercury is smaller than some of the moons of Jupiter and Saturn.

Venus

The second planet from the Sun, has an almost circular orbit. It passes closer to Earth than any other planet.

But the dense, cloudy atmosphere does not allow you to directly see its surface. Atmosphere: CO 2 (97%), N2 (approx. 3%), H 2 O (0.05%), impurities CO, SO 2, HCl, HF. Due to the greenhouse effect, the surface temperature warms up to hundreds of degrees. The atmosphere, which is a dense blanket of carbon dioxide, traps the heat that comes from the sun. This leads to the fact that the temperature of the atmosphere is much higher than in the oven. Radar images show a very wide variety of craters, volcanoes and mountains. There are several very large volcanoes, up to 3 km high. and hundreds of kilometers wide. The outpouring of lava on Venus takes much longer than on Earth. The surface pressure is about 107 Pa. The surface rocks of Venus are similar in composition to terrestrial sedimentary rocks.
Finding Venus in the sky is easier than any other planet. Its dense clouds reflect sunlight well, making the planet bright in our sky. Every seven months for several weeks, Venus is the brightest object in the western sky in the evening. Three and a half months later, it rises three hours before the Sun, becoming the brilliant "morning star" of the eastern sky. Venus can be observed an hour after sunset or an hour before sunrise. Venus has no satellites.

3rd from Sol no planet. The speed of the Earth's circulation in an elliptical orbit around the Sun is - 29.765 km / s. The inclination of the earth's axis to the plane of the ecliptic is 66 o 33 "22"". The Earth has a natural satellite - the Moon. The Earth has a magneticmagnetic and electric fields. The Earth was formed 4.7 billion years ago from gas scattered in the protosolar system- dust substances. The composition of the Earth is dominated by: iron (34.6%), oxygen (29.5%), silicon (15.2%), magnesium (12.7%). The pressure in the center of the planet is 3.6 * 10 11 Pa, the density is about 12,500 kg / m 3, the temperature is 5000-6000 o C. Most of thethe surface is occupied by the World Ocean (361.1 million km 2; 70.8%); land is 149.1 million km 2 and forms six motherscoves and islands. It rises above the level of the world ocean by an average of 875 meters (the highest height is 8848 meters - the city of Chomolungma). Mountains occupy 30% of the land, deserts cover about 20% of the land surface, savannas and light forests - about 20%, forests - about 30%, glaciers - 10%. The average depth of the ocean is about 3800 meters, the greatest is 11022 meters (the Mariana Trench in the Pacific Ocean), the volume of water is 1370 million km 3, the average salinity is 35 g / l. The atmosphere of the Earth, the total mass of which is 5.15 * 10 15 tons, consists of air - a mixture of mainly nitrogen (78.1%) and oxygen (21%), the rest is water vapor, carbon dioxide, noble and other gases. About 3-3.5 billion years ago, as a result of the natural evolution of matter, life arose on Earth, and the development of the biosphere began.

Mars

The fourth planet from the Sun, similar to Earth, but smaller and colder. Mars has deep canyonsgiant volcanoes and vast deserts. Around the Red Planet, as Mars is also called, two small moons fly: Phobos and Deimos. Mars is the planet next to the Earth, if you count from the Sun, and the only space world, apart from the Moon, that can already be reached with modern rockets. For astronauts, this four-year journey could be the next frontier in space exploration. Near the equator of Mars, in the region called Tharsis, there are volcanoes of colossal proportions. Tarsis is the name that astronomers gave to a hill that has 400 km. wide and about 10 km. in height. There are four volcanoes on this plateau, each of which is simply a giant in comparison with any terrestrial volcano. The most grandiose volcano of Tarsis, Mount Olympus, rises above the surrounding area for 27 km. About two-thirds of the surface of Mars is a mountainous area with a large number of impact craters and surrounded by debris of hard rocks. Near the volcanoes of Tharsis snakes a vast system of canyons about a quarter of the equator long. The Mariner Valley is 600 km wide, and its depth is such that Mount Everest would sink entirely to its bottom. Sheer cliffs rise thousands of meters, from the bottom of the valley to the plateau above. In ancient times, there was a lot of water on Mars, large rivers flowed on the surface of this planet. Ice caps lie at the South and North Poles of Mars. But this ice does not consist of water, but of frozen atmospheric carbon dioxide (it freezes at a temperature of -100 o C). Scientists believe that surface water is stored in the form of ice blocks buried in the ground, especially in the polar regions. Atmospheric composition: CO 2 (95%), N 2 (2.5%), Ar (1.5 - 2%), CO (0.06%), H 2 O (up to 0.1%); pressure near the surface is 5-7 hPa. In total, about 30 interplanetary space stations were sent to Mars.

Jupiter

The fifth planet from the Sun, the largest planet in the solar system. Jupiter is not a solid planet. Unlike the four solid planets closest to the Sun, Jupiter is a gas ball. The composition of the atmosphere: H 2 (85%), CH 4 , NH 3 , He (14%). Jupiter's gas composition is very similar to that of the sun. Jupiter is a powerful source of thermal radio emission. Jupiter has 16 satellites (Adrastea, Metis, Amalthea, Thebe, Io, Lysitea, Elara, Ananke, Karma, Pasiphe, Sinope, Europa, Ganymede, Callisto, Leda, Himalia), as well as a ring 20,000 km wide, almost closely adjacent to planet. Jupiter's rotation speed is so great that the planet bulges along the equator. In addition, such a rapid rotation causes very strong winds in the upper atmosphere, where the clouds are stretched out in long colorful ribbons. There are a very large number of vortex spots in the clouds of Jupiter. The largest of them, the so-called Great Red Spot, is larger than the Earth. The Great Red Spot is a huge storm in Jupiter's atmosphere that has been observed for 300 years. Inside the planet, under enormous pressure, hydrogen from a gas turns into a liquid, and then from a liquid into a solid. At a depth of 100 km. there is a vast ocean of liquid hydrogen. Below 17000 km. hydrogen is compressed so strongly that its atoms are destroyed. And then it starts behaving like metal; in this state, it easily conducts electricity. An electric current flowing in metallic hydrogen creates a strong magnetic field around Jupiter.

Saturn

The sixth planet from the Sun, has an amazing system of rings. Due to the rapid rotation around its axis, Saturn seems to be flattened at the poles. The wind speed at the equator reaches 1800 km/h. The rings of Saturn are 400,000 km wide, but they are only a few tens of meters thick. The inner parts of the rings revolve around Saturn faster than the outer ones. The rings are mostly made up of billions of small particles, each of which orbits Saturn as a separate microscopic moon. Probably, these "microsatellites" consist of water ice or rocks covered with ice. Their size ranges from a few centimeters to tens of meters. There are also larger objects in the rings - stone blocks and fragments up to hundreds of meters in diameter. The gaps between the rings arise under the influence of the gravitational forces of seventeen moons (Hyperion, Mimas, Tethys, Titan, Enceladus, etc.), which cause the rings to split. The composition of the atmosphere includes: CH 4 , H 2 , He, NH 3 .

Uranus

7th from Sun planet. It was discovered in 1781 by the English astronomer William Herschel, and named after Greek about the sky god Uranus. The orientation of Uranus in space differs from the rest of the planets of the solar system - its axis of rotation lies, as it were, "on its side" relative to the plane of revolution of this planet around the Sun. The axis of rotation is inclined at an angle of 98 o . As a result, the planet is turned to the Sun alternately with the north pole, then the south, then the equator, then the middle latitudes. Uranus has more than 27 satellites (Miranda, Ariel, Umbriel, Titania, Oberon, Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Belinda, Pack, etc.) and a system of rings. At the center of Uranus is a core composed of stone and iron. The composition of the atmosphere includes: H 2 , He, CH 4 (14%).

Neptune

E its orbit intersects with Pluto's in some places. The equatorial diameter is the same as that of Uranus, although ra Neptune is located 1627 million km farther from Uranus (Uranus is located 2869 million km from the Sun). Based on these data, we can conclude that this planet could not be noticed in the 17th century. One of the striking achievements of science, one of the evidence of the unlimited cognizability of nature was the discovery of the planet Neptune by calculations - "on the tip of a pen." Uranus - the planet following Saturn, which for many centuries was considered the most distant planet, was discovered by V. Herschel at the end of the 18th century. Uranus is hardly visible to the naked eye. By the 40s of the XIX century. accurate observations have shown that Uranus deviates just barely from the path it should follow, given the perturbations from all the known planets. Thus the theory of motion of celestial bodies, so rigorous and precise, was put to the test. Le Verrier (in France) and Adams (in England) suggested that if perturbations from the known planets do not explain the deviation in the motion of Uranus, it means that the attraction of an as yet unknown body acts on it. They almost simultaneously calculated where behind Uranus there should be an unknown body that produces these deviations by its attraction. They calculated the orbit of the unknown planet, its mass and indicated the place in the sky where the unknown planet should have been at the given time. This planet was found in a telescope at the place indicated by them in 1846. It was called Neptune. Neptune is not visible to the naked eye. On this planet, winds blow at speeds up to 2400 km / h, directed against the rotation of the planet. These are the strongest winds in the solar system.
Atmospheric composition: H 2 , He, CH 4 . It has 6 satellites (one of them is Triton).
Neptune is the god of the seas in Roman mythology.

Planets of the solar system - a bit of history

Previously, a planet was considered to be any body that revolves around a star, glows with light reflected from it, and has a size larger than that of asteroids.

Even in ancient Greece, seven luminous bodies were mentioned that move across the sky against the background of fixed stars. These cosmic bodies were: Sun, Mercury, Venus, Moon, Mars, Jupiter and Saturn. 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 not the Earth, but the Sun, should be in the center of the planetary system. Therefore, the Sun and the 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.

Pluto was considered the last discovered planet in the solar system from 1930 until recently.

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

A planet is a celestial body that must satisfy four conditions:

In turn, the polar 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

The 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. The composition of gas giants consists mainly of hydrogen and helium.

The sizes of the planets in the solar system vary both within groups and between groups. So, the gas giants are much larger and more massive than the terrestrial planets.

Closest to the Sun is Mercury, then as far as the distance: 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.

The sun planet is a 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 over 5,000 degrees Kelvin, and the core temperature is over 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 complete revolution around it in about 230-250 million years! For comparison, the Earth makes a complete revolution around the Sun in 1 year.

Mercury planet

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

The surface of the planet is covered with craters that arose 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 highly rarefied, consists mainly of helium and is blown by the solar wind. Since the planet is located very close to the Sun and does not have an atmosphere that would keep warm at night, the temperature on the surface ranges from -180 to +440 degrees Celsius.

By earthly standards, Mercury makes a complete revolution around the Sun in 88 days. On the other hand, a Mercury day is equal to 176 Earth days.

Venus planet

Venus is the second closest planet to the Sun in the solar system. Venus is only slightly smaller than Earth, which is why it is sometimes referred to as "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 the earth.

Carbon dioxide and, as a result, the greenhouse effect, a dense atmosphere, as well as proximity to the Sun, allow Venus to carry 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.

Planet Earth

Earth is the only known planet in the universe today that has life on it. 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 atmosphere of the Earth is fundamentally different from the atmospheres of other planets due to the presence of life. Most of the atmosphere is nitrogen, but it also contains oxygen, argon, carbon dioxide and water vapor. The ozone layer and the Earth's magnetic field, in turn, weaken the life-threatening effects of solar and cosmic radiation.

Due to the carbon dioxide contained in the atmosphere, the greenhouse effect also takes place on Earth. It does not appear as strongly as on Venus, but without it, the air temperature would be approximately 40 ° C lower. Without the 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 oceans, the remaining 29% are continents and islands.

mars planet

Mars is the seventh largest planet in the solar system. The "Red Planet", as it is also called due to the presence of a large amount of iron oxide in the soil. Mars has two moons: Deimos and Phobos.

The atmosphere of Mars is highly rarefied, 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 drops in some places reach 40 degrees during the day.

Distinctive features of the surface of Mars are impact craters and volcanoes, valleys and deserts, ice polar caps like those on Earth. The highest mountain in the solar system is located on Mars: the extinct volcano Olympus, whose height is 27 km! As well as the largest canyon: the Valley of the Mariner, the depth of which reaches 11 km, and the length is 4500 km.

Jupiter planet

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 radiates a huge amount of heat, equal to 4 * 1017 watts. However, in order to become a star like the Sun, Jupiter must be another 70-80 times heavier.

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

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

saturn planet

Saturn is the second largest planet in the solar system. The hallmark of Saturn is, of course, its ring system, which consists mainly of ice 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 outer atmosphere of the planet looks calm and homogeneous, which is explained by a very dense layer of fog. However, the wind speed in some places can reach 1800 km/h.

Uranus planet

Uranus is the first planet to be discovered with a telescope, and also the only planet in the solar system that wraps around the sun, "lying on its side."

Uranus has 27 moons named after Shakespearean heroes. The largest of them are Oberon, Titania and Umbriel.

The composition of the planet differs from the gas giants in the presence of a large number of high-temperature modifications of ice. Therefore, along with Neptune, scientists have identified Uranus in the category of "ice giants". 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 planet

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

To date, 13 satellites of Neptune are known to science. The largest of them - Triton - is the only satellite that moves in the opposite direction 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.

The composition of Neptune is very similar to Uranus, therefore it is the second "ice giant". However, like Jupiter and Saturn, Neptune has an internal source of heat and radiates 2.5 times more energy than it receives from the Sun.

The planet's blue color comes from traces of methane in the outer atmosphere.

Conclusion

Pluto, unfortunately, did not have time to get into our parade of planets in the solar system. But it is absolutely not worth worrying about this, because all the planets remain in their places, despite changes in scientific views and concepts.

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