The first 4 planets from the sun. Planets of the solar system: their order and history of names

This is a system of planets, in the center of which there is a bright star, a source of energy, heat and light - the Sun.
According to one theory, the Sun was formed along with the Solar System about 4.5 billion years ago as a result of the explosion of one or more supernovae. Initially, the Solar System was a cloud of gas and dust particles, which, in motion and under the influence of their mass, formed a disk in which a new star, the Sun, and our entire Solar System arose.

At the center of the solar system is the Sun, around which nine large planets revolve in orbit. Since the Sun is displaced from the center of planetary orbits, during the cycle of revolution around the Sun the planets either approach or move away in their orbits.

There are two groups of planets:

Terrestrial planets: And . These planets are small in size with a rocky surface and are closest to the Sun.

Giant planets: And . These are large planets, consisting mainly of gas and characterized by the presence of rings consisting of icy dust and many rocky pieces.

But does not fall into any group because, despite its location in the solar system, it is located too far from the Sun and has a very small diameter, only 2320 km, which is half the diameter of Mercury.

Planets of the Solar System

Let's begin a fascinating acquaintance with the planets of the Solar System in order of their location from the Sun, and also consider their main satellites and some other space objects (comets, asteroids, meteorites) in the gigantic expanses of our planetary system.

Rings and moons of Jupiter: Europa, Io, Ganymede, Callisto and others...
The planet Jupiter is surrounded by a whole family of 16 satellites, and each of them has its own unique features...

Rings and moons of Saturn: Titan, Enceladus and others...
Not only the planet Saturn has characteristic rings, but also other giant planets. Around Saturn, the rings are especially clearly visible, because they consist of billions of small particles that revolve around the planet, in addition to several rings, Saturn has 18 satellites, one of which is Titan, its diameter is 5000 km, which makes it the largest satellite in the solar system...

Rings and moons of Uranus: Titania, Oberon and others...
The planet Uranus has 17 satellites and, like other giant planets, there are thin rings surrounding the planet that have practically no ability to reflect light, so they were discovered not so long ago in 1977, completely by accident...

Rings and moons of Neptune: Triton, Nereid and others...
Initially, before the exploration of Neptune by the Voyager 2 spacecraft, two satellites of the planet were known - Triton and Nerida. An interesting fact is that the Triton satellite has a reverse direction of orbital motion; strange volcanoes were also discovered on the satellite that erupted nitrogen gas like geysers, spreading a dark-colored mass (from liquid to vapor) many kilometers into the atmosphere. During its mission, Voyager 2 discovered six more moons of the planet Neptune...

It is no coincidence that each cosmic object finds its place in space; billions of particles are formed into a single body over billions of years so that we can see this or that phenomenon in the starry sky. The names of the planets of the solar system in order from the star Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Knowledge of the order and structure of nearby space objects is not only an indicator of a person’s erudition, but also a way to expand knowledge about the world around us, which has a direct impact on each of us.

Nature, which includes deep space objects, is a complex mechanism, each element of which is inextricably linked with other objects.

The solar system includes a group of objects revolving around one star - the Sun. It is part of the Milky Way galaxy.

Interesting facts:

1. The approximate time since formation is 4,570,000,000 years.
2. The sum of the masses of all elements of the system is about 1.0014 M☉ (Solar mass).
3. The sum of the masses of the planets is 2% of the mass of the system.
4. Mercury, Venus, Earth and Mars (the closest 4 objects to the star) include a large number of silicates and metals, while more distant bodies - Jupiter, Saturn, Uranus and Neptune - consist of hydrogen (H), admixtures of methane and carbon monoxide gas
5. 6 out of 8 have one or more satellites in their orbit.

Pay attention! In addition to the planets, the planetary mechanism includes numerous small bodies.

The figure shows a diagram of the solar system.

Location of planets in the solar system

Order and characteristics

After large extraterrestrial bodies were discovered in the Kuiper Belt region in 2006, it was decided to exclude Pluto from the list of planets. Pluto, like Eris, Haumea and Makemake, was reclassified into the group of dwarf planets.

Useful video: what you need to know about the Solar System?

Planets of the solar system

Astronomy is evolving. Thanks to advances in physics and technological developments, the accuracy of remote exploration of various extraterrestrial bodies is increasing. What was previously only available in science fiction books is becoming more and more real every year. Let's consider all the planets of the solar system in order with their names.

Sun

The sun is the central element of our planetary system.

Star Features:

• belongs to the category of yellow dwarfs of class G2;
• the brightness of the star gradually increases;
• as a star of type 1 stellar population, formed at the late stages of the formation of the universe, the Sun is distinguished by a significant content of heavy elements (elements heavier than He and H);
• Currently, several stars are known that are similar to the Sun in structure, age and composition.

The change in brightness, surface temperature and size of stars is clearly shown on the Hertzsprung-Russell diagram.

The photo shows a Hertzsprung-Russell plot.

Hertzsprung-Russell plot

Most known stars are not as bright and emit less heat than the Sun (85%).

It should be noted that the Sun is in the middle of its development and its supply of hydrogen has not yet come to an end.

Inner Solar System

The terrestrial group of cosmic bodies belongs to this part of the cosmic mechanism.

Specifications:

1. Small diameter (compared to the Sun and gas giants).
2. High density structure, hard surface, variety of elements in the composition.
3. Have an atmosphere (with the exception of Mercury).
4. Similar structure, including core, mantle and crust (with the exception of Mercury).
5. The presence of a relief surface.
6. Absence or a small number of satellites.
7. Weak attraction.

It is important to remember that each planet is unique and amazing in its own way.

The internal structure can be seen in the photo.

Mercury is the first extraterrestrial body from the star Sun.

Peculiarities:

• a revolution around the star takes 88 Earth days;
• length of day - 59 Earth days;
• average temperature during the day is +430 degrees, at night -170 degrees;
• lack of accompanying elements;
• Impact craters and blade-like ledges of impressive size are observed on the surface of the object;
• rarefied atmosphere.

This is one of the most interesting planets in the solar system. What is surprising is the large size of the core with a thin layer of bark on the surface. One hypothesis is that the light structures that previously covered Mercury were torn off by a collision with another body, causing the planet to shrink significantly in size.

Venus is the second planet from the Sun. It has a structure similar to our Earth, distinguishing a mantle and a core.

Peculiarities:

• shows signs of internal activity;
• has a high atmospheric density (90 times denser than the earth’s);
• a small amount of water was detected on the surface;
• surface temperature more than +400 degrees;
• the length of a day on Venus is 243.02 Earth days;
• Venus rotates in the opposite direction compared to most objects;
• has no satellites.

Venus does not have a magnetic field, but due to the high density of the atmosphere, the planet does not deplete.

Earth

The Earth is the third object from the star and our home. A distinctive feature is the presence of a wide variety of living beings.

Peculiarities:

• development of the atmosphere, hydrosphere and atmosphere;
• more than 70% of the surface is covered with water;
• the magnetic field is quite strong;
• 1 revolution around its axis is equal to 24 hours, a revolution around the star is 365 days;
• the presence of moving tectonic plates;
• satellite - Moon;
• many parameters of extraterrestrial objects (mass, orbital time, surface area) are recorded relative to the corresponding indicators of our planet.

The presence of life on other space objects has not been fully elucidated.

Mars is the fourth planet from the Sun and is significantly smaller in size than Earth or Venus.

Peculiarities:

• a full revolution around a star is equal to 687 Earth days;
• has an atmosphere;
• has traces of water and ice caps at the poles;
• pressure 6.1 mbar (0.6% of Earth's);
• volcanoes were discovered on the surface of Mars, the height of the largest of them (Olympus) is 21.2 km;
• traces of geological activity were identified;
• satellites - Deimos and Phobos.

Mars is the most studied space object in our planetary system after Earth.

Gas giants

The outer region of the planetary mechanism includes the gas giants, their moons, the Kuiper belt, the Scattered Disk, and the Oort clouds.

Features of gas giants:

1. Large size and weight.
2. They do not have a solid surface and consist of substances in a gaseous state.
3. The core consists of liquefied metal H.
4. High rotation speed.
5. Pronounced gravitational field.
6. A large number of satellites.
7. Presence of rings.

Gas giants are significantly different from other planets in the solar system; it is difficult to imagine that life occurs on them. Nevertheless, their presence is reflected, including on Earth. For example, the gravitational field of Jupiter attracts a significant number of cosmic bodies, the fall of which to the surface of the Earth could lead to a catastrophe of immense proportions.

The internal structure is shown in the figure.

Internal structure

Jupiter is the first gas giant and the fifth planet from the Sun.

Peculiarities:

• contains H and He;
• high internal temperature detected;
• the period of revolution around the star is 4333 Earth days;
• the period of revolution around its axis is 10 Earth hours;
• the largest satellites - Ganymede, Callisto, Io and Europa - have a structure similar to the terrestrial group;
• the largest satellite Ganymede (radius 2634 km) exceeds Mercury in size.

According to one theory, it is believed that Jupiter is a star that has stopped in its development. One of the important confirmations of this idea is the numerous satellites orbiting the gas giant according to the model of the system.

Saturn is the second gas giant and the sixth planet from the luminary. A distinctive feature of the body is the rings visible from a long distance.

Peculiarities:

• a revolution around a star takes 10,759 Earth days;
• length of day - 10.5 Earth hours;
• the least dense body in the system;
• the satellites Titan and Enceladus are distinguished by the presence of geological activity;
• Saturn's moon Titan has an atmosphere and is larger than Mercury.

Previously, Saturn's rings were considered a unique phenomenon, but in the recent past, rings were discovered on all gas giants, even on one of Saturn's moons, Rhea.

Uranus is the lightest of the gas giants and the seventh planet from our main star.

Peculiarities:

• surface temperature -224 degrees;
• axis tilt - 98°;
• a revolution around a star takes 30,685 Earth days;
• a revolution around its axis takes 17 Earth hours;
• the largest satellites are Titania, Oberon, Umbriel, Ariel and Miranda.

Interesting fact! Due to the tilt of its rotation, Uranus appears to be rolling on one side.

Neptune

Neptune is the last, eighth planet from the Sun.

Unique facts about the celestial body:

• a revolution around a star occurs within 60,190 Earth days;
• wind speeds can be up to 260 meters per second;
• the largest satellite, Triton, is distinguished by the presence of geological activity and geysers of liquid nitrogen, atmosphere;
• Triton rotates in the opposite direction relative to its other moons.

An amazing fact is that Neptune is the only body in the system whose presence was determined through mathematical calculations. The location of the terrestrial planets and other gas giants was determined using powerful telescopes.

Planets of the solar system: planets of the solar system

Conclusion

The Universe is limitless and amazing, there are many Galaxies and planets that humanity has yet to learn about. That is why one of the fundamental tasks of modern astronomy is the discovery of new, previously unexplored space objects, and determination of the possibility of the existence of other forms of life.

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 of the Big Bang. The origin of the Solar System is explained by the same laws that operated and continue to operate today in the fields of 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. The first mechanical heliocentric model of the solar system with a clock mechanism was presented to the 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 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. Objects of extraterrestrial origin are concentrated here in huge numbers, mainly represented by asteroids and small planets. It is these irregularly shaped fragments that are considered in human culture to be the remains of the protoplanet Phaethon, which perished 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.

Pluto, formerly one of the major planets, 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 exploring 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 located at a distance of one light year 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, the back side of the planet is immersed in universal cold with temperatures up 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 the inner planets of the solar system, located at a distance of approximately 150 million km from the Sun. 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 difficult 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 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 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, 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 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 raises a new question: how many planets were there 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.

In conclusion

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 visit the inner regions of the Solar System with a periodicity of 20-150 years, 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

solar system is a system of celestial bodies welded together by 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 by gravitational compression gas and dust cloud approximately 4.57 billion years ago.

Sun

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Mercury is the planet closest 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, quickly moving across the sky following the Sun, received his name. Mercury has been known since ancient times, but ancient astronomers did not immediately realize that they saw the same star in the morning and evening. Mercury is closer to the Sun than the Earth: the average distance from the Sun is 0.387 AU, and the distance to Earth ranges 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. Mercury's axis is almost perpendicular to the plane of its orbit, and the orbit itself is very elongated (eccentricity e = 0.206). The average speed of Mercury's 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, relates to the period of rotation around its axis (58.65 Earth days) as 3/2. Mercury completes three full revolutions 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 during the formation of the planets 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 its 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. Thanks to the greenhouse effect, the surface temperature heats up to hundreds of degrees. The atmosphere, a thick blanket of carbon dioxide, traps heat coming from the Sun. This results in the temperature of the atmosphere being 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 pressure at the surface 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. For a few weeks every seven months, Venus is the brightest object in the western sky in the evenings. Three and a half months later, it rises three hours earlier than the Sun, becoming the sparkling “morning star” of the eastern sky. Venus can be observed an hour after sunset or an hour before sunrise. Venus has no satellites.

Third from Sol ntsa planet. The speed of the Earth's revolution in an elliptical orbit around the Sun is 29.765 km/s. The inclination of the earth's axis to the ecliptic plane is 66 o 33 "22". The Earth has a natural satellite - the Moon. The Earth has a magnetic fieldIT and electric fields. The Earth was formed 4.7 billion years ago from gas dispersed 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 the timeThe surface is occupied by the World Ocean (361.1 million km 2; 70.8%); the land area is 149.1 million km 2 and forms six motherscoves and islands. It rises above the level of the world's oceans by an average of 875 meters (the highest altitude is 8848 meters - the city of Chomolungma). Mountains occupy 30% of the land, deserts cover about 20% of the land surface, savannas and woodlands - about 20%, forests - about 30%, glaciers - 10%. The average depth of the ocean is about 3800 meters, the greatest is 11022 meters (Mariana Trench in the Pacific Ocean), the volume of water is 1370 million km 3, the average salinity is 35 g/l. The Earth's atmosphere, 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 cooler. Mars has deep canyonsgiant volcanoes and vast deserts. There are two small moons flying around the Red Planet, as Mars is also called: Phobos and Deimos. Mars is the next planet after the Earth, if you count from the Sun, and the only cosmic world besides the Moon that can already be reached with the help of modern rockets. For astronauts, this four-year journey could represent the next frontier in space exploration. Near the equator of Mars, in an area called Tharsis, there are volcanoes of colossal size. Tarsis is the name that astronomers gave to the hill, which has 400 km. wide and about 10 km. in height. There are four volcanoes on this plateau, each of which is simply gigantic compared to any terrestrial volcano. The largest volcano on Tharsis, Mount Olympus, rises 27 km above the surrounding area. About two-thirds of Mars' surface is mountainous, with large numbers of impact craters surrounded by rock debris. Near the volcanoes of Tharsis, a vast system of canyons snakes around the length of about a quarter of the equator. The Valles Marineris 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 valley floor to the plateau above. In ancient times, there was a lot of water on Mars; large rivers flowed across the surface of this planet. There are ice caps at the South and North Poles of Mars. But this ice does not consist of water, but of frozen atmospheric carbon dioxide (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 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 at 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 rocky planet. Unlike the four rocky planets closest to the Sun, Jupiter is a gas ball. Atmospheric composition: H 2 (85%), CH 4, NH 3, He (14%). Jupiter's gas composition is very similar to the sun's. Jupiter is a powerful source of thermal radio emission. Jupiter has 16 satellites (Adrastea, Metis, Amalthea, Thebe, Io, Lysithea, Elara, Ananke, Karme, Pasiphae, 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 high that the planet bulges along the equator. In addition, this rapid rotation causes very strong winds in the upper atmosphere, where clouds stretch out into 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 turns from a gas into a liquid, and then from a liquid into a solid. At a depth of 100 km. there is a boundless ocean of liquid hydrogen. Below 17,000 km. hydrogen is compressed so tightly that its atoms are destroyed. And then it begins to behave like metal; in this state it easily conducts electricity. The electric current flowing in metallic hydrogen creates a strong magnetic field around Jupiter.

Saturn

The sixth planet from the Sun has an amazing ring system. Due to its rapid rotation around its axis, Saturn seems to be flattened at the poles. Wind speeds at the equator reach 1800 km/h. The width of Saturn's rings is 400,000 km, but they are only a few tens of meters thick. The inner parts of the rings rotate around Saturn faster than the outer ones. The rings are primarily made up of billions of small particles, each orbiting Saturn as its own microscopic satellite. These "micro-satellites" are likely made of water ice or rocks covered in ice. Their size ranges from several 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

Seventh 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 other 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 faces the Sun alternately with the north pole, the south pole, the equator, and the middle latitudes. Uranus has more than 27 satellites (Miranda, Ariel, Umbriel, Titania, Oberon, Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Belinda, Peck, etc.) and a system of rings. At the center of Uranus is a core made of rock and iron. The composition of the atmosphere includes: H 2, He, CH 4 (14%).

Neptune

E Its orbit intersects with Pluto's orbit in some places. The equatorial diameter is the same as that of Uranus, although ra Neptune is located 1627 million km further 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 cognition of nature was the discovery of the planet Neptune through calculations - “at the tip of a pen.” Uranus, the planet next to Saturn, which for many centuries was considered the most distant planet, was discovered by W. 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 barely noticeably from the path it should follow, taking into account the disturbances from all the known planets. Thus, the theory of the movement of celestial bodies, so strict and accurate, was put to the test. Le Verrier (in France) and Adams (in England) suggested that if disturbances from the known planets do not explain the deviation in the movement of Uranus, then it is affected by the attraction of an as yet unknown body. They almost simultaneously calculated where behind Uranus there should be an unknown body producing these deviations with its gravity. They calculated the orbit of the unknown planet, its mass and indicated the place in the sky where the unknown planet should have been located at that time. This planet was found through a telescope at the place they indicated in 1846. It was named Neptune. Neptune is not visible to the naked eye. On this planet, winds blow at speeds of 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. Has 6 satellites (one of them is Triton).
Neptune is the god of the seas in Roman mythology.

Planets of the solar system - 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.
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 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 should not be a star.

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

solar system is a planetary system that consists of a central star - the Sun - and all the natural space objects orbiting 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.

The sun planet 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 planet

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 planet

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.

Planet 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 planet

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. The highest mountain in the solar system is located on Mars: 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 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 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 planet

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 planet

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 planet

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.

Neptune's composition 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 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 .