Solar system concept. When will the solar system die? Geocentric and heliocentric systems

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 chunks.

And here 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...

What is the solar system in which we live? The answer will be as follows: this is our central star, the Sun and all the cosmic bodies that revolve around it. These are large and small planets, as well as their satellites, comets, asteroids, gases and cosmic dust.

The name of the solar system was given by the name of its star. In a broad sense, “solar” often means any star system.

How did the solar system originate?

According to scientists, the Solar system was formed from a giant interstellar cloud of dust and gases due to gravitational collapse in a separate part of it. As a result, a protostar was formed in the center, which then turned into a star - the Sun, and a protoplanetary disk of enormous size, from which all the components of the Solar system listed above were subsequently formed. The process, scientists believe, began about 4.6 billion years ago. This hypothesis was called the nebular hypothesis. Thanks to Emmanuel Swedenborg, Immanuel Kant and Pierre-Simon Laplace, who proposed it back in the 18th century, it eventually became generally accepted, but over the course of many decades it was refined, new data was introduced into it taking into account the knowledge of modern sciences. Thus, it is assumed that due to the increase and intensification of collisions of particles with each other, the temperature of the object increased, and after it reached several thousand kelvins, the protostar acquired a glow. When the temperature reached millions of kelvins, a thermonuclear fusion reaction began in the center of the future Sun - the conversion of hydrogen into helium. It turned into a star.

The sun and its features

Scientists classify our star as a yellow dwarf (G2V) according to its spectral classification. This is the closest star to us, its light reaches the surface of the planet in just 8.31 seconds. From Earth, the radiation appears to have a yellow tint, although in reality it is almost white.

The main components of our luminary are helium and hydrogen. In addition, thanks to spectral analysis, it was discovered that the Sun contains iron, neon, chromium, calcium, carbon, magnesium, sulfur, silicon, and nitrogen. Thanks to the thermonuclear reaction continuously occurring in its depths, all life on Earth receives the necessary energy. Sunlight is an integral component of photosynthesis, which produces oxygen. Without the sun's rays it would not have been possible, and therefore an atmosphere suitable for the protein form of life would not have been able to form.

Mercury

This is the closest planet to our star. Together with Earth, Venus and Mars, it belongs to the so-called terrestrial planets. Mercury received its name because of its high speed of movement, which, according to myths, distinguished the fleet-footed ancient god. The Mercury year is 88 days.

The planet is small, its radius is only 2439.7, and it is smaller in size than some of the large satellites of the giant planets, Ganymede and Titan. However, unlike them, Mercury is quite heavy (3.3 x 10 23 kg), and its density is only slightly behind that of Earth. This is due to the presence of a heavy dense core of iron on the planet.

There is no change of seasons on the planet. Its desert surface resembles that of the Moon. It is also covered with craters, but is even less suitable for life. So, on the day side of Mercury the temperature reaches +510 °C, and on the night side -210 °C. These are the sharpest changes in the entire solar system. The atmosphere of the planet is very thin and rarefied.

Venus

This planet, named after the ancient Greek goddess of love, is more similar than others in the solar system to the Earth in its physical parameters - mass, density, size, volume. For a long time they were considered twin planets, but over time it became clear that their differences are enormous. So, Venus has no satellites at all. Its atmosphere consists of almost 98% carbon dioxide, and the pressure on the planet’s surface is 92 times higher than Earth’s! Clouds above the surface of the planet, consisting of sulfuric acid vapor, never dissipate, and the temperature here reaches +434 ° C. There is acid rain on the planet and thunderstorms are raging. There is high volcanic activity here. Life, as we understand it, cannot exist on Venus; moreover, descending spacecraft cannot survive in such an atmosphere for long.

This planet is clearly visible in the night sky. This is the third brightest object for an earthly observer; it shines with white light and is brighter than all the stars. The distance to the Sun is 108 million km. It revolves around the Sun in 224 Earth days, and around its own axis in 243.

Earth and Mars

These are the last planets of the so-called terrestrial group, whose representatives are characterized by the presence of a solid surface. Their structure includes a core, mantle and crust (only Mercury does not have it).

Mars has a mass equal to 10% of the mass of the Earth, which, in turn, is 5.9726 10 24 kg. Its diameter is 6780 km, almost half that of our planet. Mars is the seventh largest planet in the solar system. Unlike the Earth, 71% of whose surface is covered by oceans, Mars is entirely dry land. The water was preserved beneath the planet's surface in the form of a massive ice sheet. Its surface has a reddish tint due to the high content of iron oxide in the form of maghemite.

The atmosphere of Mars is very rarefied, and the pressure on the surface of the planet is 160 times less than what we are used to. On the surface of the planet there are impact craters, volcanoes, depressions, deserts and valleys, and at the poles there are ice caps, just like on Earth.

Martian days are slightly longer than Earth ones, and the year is 668.6 days. Unlike the Earth, which has one moon, the planet has two irregular satellites - Phobos and Deimos. Both of them, like the Moon to the Earth, are constantly turned to Mars with the same side. Phobos is gradually approaching the surface of its planet, moving in a spiral, and will likely fall onto it over time or break into pieces. Deimos, on the contrary, is gradually moving away from Mars and may leave its orbit in the distant future.

Between the orbits of Mars and the next planet, Jupiter, there is an asteroid belt consisting of small celestial bodies.

Jupiter and Saturn

Which planet is the largest? There are four gas giants in the solar system: Jupiter, Saturn, Uranus and Neptune. Jupiter has the largest size. Its atmosphere, like that of the Sun, consists predominantly of hydrogen. The fifth planet, named after the thunder god, has an average radius of 69,911 km and a mass 318 times that of Earth. The planet's magnetic field is 12 times stronger than the Earth's. Its surface is hidden under opaque clouds. So far, scientists are finding it difficult to say with certainty what processes can occur under this dense veil. It is assumed that there is a boiling hydrogen ocean on the surface of Jupiter. Astronomers consider this planet a “failed star” due to some similarity in their parameters.

Jupiter has 39 satellites, 4 of which - Io, Europa, Ganymede and Callisto - were discovered by Galileo.

Saturn is slightly smaller than Jupiter, it is the second largest among the planets. This is the sixth, next planet, also consisting of hydrogen with admixtures of helium, a small amount of ammonia, methane, and water. Hurricanes rage here, the speed of which can reach 1800 km/h! Saturn's magnetic field is not as powerful as Jupiter's, but stronger than Earth's. Both Jupiter and Saturn are somewhat flattened at the poles due to rotation. Saturn is 95 times heavier than earth, but its density is less than that of water. This is the least dense celestial body in our system.

A year on Saturn lasts 29.4 Earth years, a day is 10 hours 42 minutes. (Jupiter has a year of 11.86 Earth years, a day of 9 hours 56 minutes). It has a system of rings consisting of solid particles of various sizes. Presumably, these may be the remains of a destroyed satellite of the planet. In total, Saturn has 62 satellites.

Uranus and Neptune - the last planets

The seventh planet of the solar system is Uranus. It is 2.9 billion km away from the Sun. Uranus is the third largest among the planets of the Solar System (average radius - 25,362 km) and the fourth largest in mass (14.6 times greater than Earth's). A year here lasts 84 Earth years, a day lasts 17.5 hours. In the atmosphere of this planet, in addition to hydrogen and helium, methane occupies a significant volume. Therefore, for an earthly observer, Uranus has a soft blue color.

Uranus is the coldest planet in the solar system. The temperature of its atmosphere is unique: -224 °C. Scientists do not know why Uranus has a lower temperature than planets that are further from the Sun.

This planet has 27 satellites. Uranus has thin, flat rings.

Neptune, the eighth planet from the Sun, ranks fourth in size (average radius - 24,622 km) and third in mass (17 Earth's). For a gas giant, it is relatively small (only four times the size of Earth). Its atmosphere is also mainly composed of hydrogen, helium and methane. Gas clouds in its upper layers move at a record speed, the highest in the solar system - 2000 km/h! Some scientists believe that under the surface of the planet, under a layer of frozen gases and water, hidden, in turn, by the atmosphere, a solid rocky core may be hiding.

These two planets are similar in composition, which is why they are sometimes classified as a separate category - ice giants.

Minor planets

Minor planets are celestial bodies that also move around the Sun in their own orbits, but differ from other planets in their small sizes. Previously, only asteroids were classified as such, but more recently, namely since 2006, they also include Pluto, which was previously included in the list of planets of the Solar System and was the last, tenth on it. This is due to changes in terminology. Thus, minor planets now include not only asteroids, but also dwarf planets - Eris, Ceres, Makemake. They were named plutoids after Pluto. The orbits of all known dwarf planets are located beyond the orbit of Neptune, in the so-called Kuiper belt, which is much wider and more massive than the asteroid belt. Although their nature, as scientists believe, is the same: it is “unused” material left after the formation of the Solar system. Some scientists have suggested that the asteroid belt is the debris of the ninth planet, Phaeton, which died as a result of a global catastrophe.

What is known about Pluto is that it is composed primarily of ice and solid rock. The main component of its ice sheet is nitrogen. Its poles are covered with eternal snow.

This is the order of the planets of the solar system, according to modern ideas.

Parade of planets. Types of parades

This is a very interesting phenomenon for those interested in astronomy. It is customary to call a parade of planets such a position in the solar system when some of them, continuously moving in their orbits, for a short time occupy a certain position for an earthly observer, as if lining up along one line.

The visible parade of planets in astronomy is the special position of the five brightest planets of the solar system for people seeing them from Earth - Mercury, Venus, Mars, as well as two giants - Jupiter and Saturn. At this time, the distance between them is relatively small and they are clearly visible in a small sector of the sky.

There are two types of parades. A large form is called when five celestial bodies line up in one line. Small - when there are only four of them. These phenomena may be visible or invisible from different parts of the globe. At the same time, a large parade occurs quite rarely - once every few decades. The small one can be observed once every few years, and the so-called mini-parade, in which only three planets participate, almost every year.

Interesting facts about our planetary system

Venus, the only one of all the major planets in the Solar System, rotates around its axis in the direction opposite to its rotation around the Sun.

The highest mountain on the major planets of the Solar System is Olympus (21.2 km, diameter - 540 km), an extinct volcano on Mars. Not long ago, on the largest asteroid of our star system, Vesta, a peak was discovered that was somewhat superior in parameters to Olympus. Perhaps it is the highest in the solar system.

The four Galilean moons of Jupiter are the largest in the Solar System.

In addition to Saturn, all gas giants, some asteroids, and Saturn's moon Rhea have rings.

Which star system is closest to us? The solar system is closest to the star system of the triple star Alpha Centauri (4.36 light years). It is assumed that planets similar to Earth may exist in it.

About planets for kids

How to explain to children what the solar system is? Her model will help here, which you can make together with the kids. To create planets, you can use plasticine or ready-made plastic (rubber) balls, as shown below. At the same time, it is necessary to maintain the relationship between the sizes of the “planets” so that the model of the solar system really helps to form in children the correct ideas about space.

You will also need toothpicks to hold our celestial bodies, and as a background you can use a dark sheet of cardboard with small dots painted on it to imitate stars. With the help of such an interactive toy, it will be easier for children to understand what the solar system is.

The future of the solar system

The article described in detail what the Solar System is. Despite its apparent stability, our Sun, like everything in nature, evolves, but this process, by our standards, is very long. The supply of hydrogen fuel in its depths is huge, but not infinite. So, according to scientists’ hypotheses, it will end in 6.4 billion years. As it burns out, the solar core will become denser and hotter, and the outer shell of the star will become wider. The star's luminosity will also increase. It is assumed that in 3.5 billion years, because of this, the climate on Earth will be similar to Venus, and life on it in the usual sense for us will no longer be possible. There will be no water left at all; under the influence of high temperatures it will evaporate into outer space. Subsequently, according to scientists, the Earth will be absorbed by the Sun and dissolve in its depths.

The outlook is not very bright. However, progress does not stand still, and perhaps by that time new technologies will allow humanity to explore other planets, over which other suns shine. After all, scientists do not yet know how many “solar” systems there are in the world. There are probably countless of them, and among them it is quite possible to find one suitable for human habitation. Which “solar” system will become our new home is not so important. Human civilization will be preserved, and another page will begin in its history...

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

Merkur th

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, which is 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 volcano on earth. The largest volcano on Tharsis, Mount Olympus, rises 27 km above the surrounding area. About two-thirds of Mars' surface is mountainous, with many 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 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

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 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 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.

From surface to core: eight journeys through the interior of the planets of the solar system.

The eight planets of our solar system are usually divided into internal (Mercury, Venus, Earth, Mars), located closer to the star, and external (Jupiter, Saturn, Uranus, Neptune). They differ not only in their distance to the Sun, but also in a number of other characteristics. The inner planets are dense and rocky, small in size; external ones are gas giants. The inner ones have very few natural satellites, or none at all; the outer ones have dozens of them, and Saturn also has rings.

Comparative sizes of the planets (from left to right: Mercury, Venus, Earth, Mars)

NASA

The basic "anatomy" of the inner planets of the solar system is simple: they all consist of a crust, mantle and core. In addition, some have a core that is divided into an inner and an outer core. For example, how does the Earth work? A solid crust covers a semi-molten mantle, and in the center there is a “two-layer” core - a liquid outer and a solid inner. By the way, it is the presence of a liquid metal core that creates a global magnetic field on the planet. On Mars, for example, everything is a little different: a solid crust, a solid mantle, a solid core - it resembles a solid billiard ball, and it has no magnetic field.

The gas giants - Saturn and Jupiter - are built completely differently. From the very name of this type of planet it is clear that they are huge balls of gas that do not have a solid surface. If someone were to descend to one of these planets, he would fall and fall towards its center, where a small solid core is located. On Uranus and Neptune, ammonia, methane and other familiar gases can only exist in solid form, so the two distant planets are huge balls of ice and solid fragments - ice giants. However, let's look at them all in order, one after another.

Mercury: a huge core

The planet closest to the Sun is one of the densest on our list: being slightly smaller than Saturn's moon Titan, it is more than twice as heavy. Only the Earth is denser than Mercury, but the Earth is large enough to be compacted by its own gravity, and if this effect did not manifest itself, then Mercury would be the champion.

A heavy iron-nickel core reigns here. It is exceptionally large for a planet of this size - according to some assumptions, the core may occupy the bulk of Mercury's volume and have a radius of about 1800-1900 km, approximately the size of the Moon. But the silicon mantle and crust surrounding it are relatively thin, no more than 500-600 km in thickness. Judging by the fact that the planet rotates slightly unevenly (like a raw egg), its core is molten and creates a global magnetic field on the planet.

The origin of Mercury's large, dense, exceptionally iron-rich core remains a mystery. It is possible that Mercury was once several times larger, and its core was not something anomalous, but as a result of a collision with an unknown body, a large piece of the crust and mantle “fell off” from it. Unfortunately, this theory has not yet been confirmed.

1. Crust, thickness - 100-300 km. 2. Mantle, thickness - 600 km. 3. Core, radius - 1800 km.

Joel Holdsworth

Venus: thick crust

The most restless and hot planet in the solar system. Its extremely dense and turbulent atmosphere consists of carbon dioxide, methane and hydrogen sulfide, which are emitted by numerous active volcanoes. The surface of Venus is 90% covered with basaltic lava, there are vast hills in the manner of the earth’s continents - it’s a pity that liquid water cannot exist here, all of it has long evaporated.

The internal structure of Venus is poorly understood. It is believed that its thick silicate crust extends several tens of kilometers deep. Judging by some data, 300-500 million years ago the planet completely renewed its crust as a result of catastrophic levels of volcanism. It is assumed that the heat that is generated in the bowels of the planet due to radioactive decay cannot be “bleeded off” gradually on Venus, as on Earth, through plate tectonics. There is no plate tectonics here, and this energy accumulates for a long time, and from time to time “breaks through” such global volcanic “storms”.

Beneath the crust of Venus begins a 3,000-kilometer layer of molten mantle of unknown composition. And since Venus belongs to the same type of planet as the Earth, it is assumed to have an iron-nickel core with a diameter of about 3000 km. On the other hand, observations did not detect Venus's own magnetic field. This may mean that the charged particles in the nucleus do not move and it is in a solid state.

Possible internal structure of Venus

Wikimedia/Vzb83

Earth: everything is perfect

Our beloved home planet has, of course, been studied better than anyone else, including geologically. If you move from its surface into depth, the solid crust will stretch up to about 40 km. The continental and oceanic crust differ sharply: the thickness of the first can reach up to 70 km, and the second practically never exceeds 10 km. The first contains a lot of volcanic rocks, the second is covered with a thick layer of sedimentary rocks.

The crust, like cracked dry mud, is divided into lithospheric plates that move relative to each other. Judging by modern data, plate tectonics is a unique phenomenon in the Solar System, which ensures constant and non-catastrophic, generally calm renewal of its surface. Very convenient for everyone!

Below, the layers of the mantle begin: upper (40-400 km), lower (up to 2700 km). The mantle accounts for the lion's share of the planet's mass - almost 70%. The mantle is even more impressive in volume: excluding the atmosphere, it occupies about 83% of our planet. The composition of the mantle most likely resembles that of stony meteorites; it is rich in silicon, iron, oxygen, and magnesium. Despite the constant stirring, the mantle should not be considered liquid in the usual sense of the word. Due to the enormous pressure, almost all of its substance is in a crystalline state.

Finally, we will get into the iron-nickel core: molten outer (at a depth of up to 5100 km) and solid inner (up to 6400 km). The core accounts for almost 30% of the Earth's mass, and convection of liquid metal in the outer core creates a global magnetic field on the planet.

General structure of planet Earth

Wikimedia/Jeremy Kemp

Mars: frozen plates

Although Mars itself is noticeably smaller than Earth, it is interesting that its surface area is approximately equal to the area of ​​Earth's landmass. But the height differences here are much more noticeable: the Red Planet has the highest mountains in the Solar System. The local Everest - Olympus Mons - rises to a height of 24 km, and huge mountain ranges above 10 km can stretch for thousands of kilometers.

The planet's crust, covered with basaltic rocks, is about 35 km thick in the northern hemisphere, and up to 130 km thick in the southern hemisphere. It is believed that there was once a movement of lithospheric plates on Mars, but at some point they stopped. Because of this, the volcanic points stopped changing their location, and the volcanoes began to grow and grow for hundreds of millions of years, creating exceptionally powerful mountain peaks.

The average density of the planet is quite low - apparently due to the small size of the core and the presence in it of a considerable (up to 20%) amount of light elements - say, sulfur. Judging by the available data, the core of Mars has a radius of about 1500-1700 km and remains only partially liquid, which means it is capable of creating only a very weak magnetic field on the planet.

Comparison of the structure of Mars and other terrestrial planets

NASA

Jupiter: gravity and light gases

Today there are no technical possibilities to study the structure of Jupiter: this planet is too large, its gravity is too strong, its atmosphere is too dense and turbulent. However, where the atmosphere ends here and the planet itself begins is difficult to say: this gas giant, in fact, does not have any clear internal boundaries.

According to existing theories, in the center of Jupiter there is a solid core with a mass 10-15 times greater than the Earth and one and a half times larger in size. However, against the backdrop of a giant planet (the mass of Jupiter is greater than the mass of all other planets in the Solar System combined), this value is completely insignificant. In general, Jupiter consists of 90% ordinary hydrogen, and the remaining 10% of helium, with a certain amount of simple hydrocarbons, nitrogen, sulfur, and oxygen. But don’t think that because of this the structure of the gas giant is “simple.”

At colossal pressure and temperature, hydrogen (and according to some data, helium) should exist here mainly in an unusual metallic form - this layer may extend to a depth of 40-50 thousand km. Here the electron breaks away from the proton and begins to behave freely, as in metals. Such liquid metallic hydrogen is naturally an excellent conductor and creates an exceptionally powerful magnetic field on the planet.

Model of Jupiter's internal structure

NASA

Saturn: self-heating system

Despite all the external differences, the absence of the famous Red Spot and the presence of even more famous rings, Saturn is very similar to its neighbor Jupiter. It is composed of 75% hydrogen and 25% helium, with trace amounts of water, methane, ammonia and solids mostly concentrated in the hot core. Like Jupiter, there is a thick layer of metallic hydrogen that creates a powerful magnetic field.

Perhaps the main difference between the two gas giants is the warm interior of Saturn: processes in the depths supply the planet with more energy than solar radiation - it emits 2.5 times more energy itself than it receives from the Sun.

There are apparently two of these processes (note that they also work on Jupiter, they are just more important on Saturn) - radioactive decay and the Kelvin - Helmholtz mechanism. The operation of this mechanism can be imagined quite easily: the planet cools, the pressure in it drops, and it contracts a little, and the compression creates additional heat. However, the presence of other effects that create energy in the bowels of Saturn cannot be ruled out.

Internal structure of Saturn

Wikimedia

Uranus: ice and stone

But on Uranus, internal heat is clearly not enough, so much so that it still requires a special explanation and puzzles scientists. Even Neptune, which is very similar to Uranus, emits heat many times more, but Uranus not only receives very little from the Sun, but also gives off about 1% of this energy. This is the coldest planet in the solar system, the temperature here can drop to 50 Kelvin.

It is believed that the bulk of Uranus is a mixture of ice - water, methane and ammonia. There is ten times less mass of hydrogen and helium here, and even less solid rock, most likely concentrated in a relatively small rocky core. The main share falls on the icy mantle. True, this ice is not exactly the substance to which we are accustomed; it is fluid and dense.

This means that the ice giant also does not have any solid surface: the gaseous atmosphere, consisting of hydrogen and helium, passes into the liquid upper layers of the planet itself without a clear boundary.

Internal structure of Uranus

Wikimedia/ FrancescoA

Neptune: Diamond Rain

Like Uranus, Neptune has a particularly prominent atmosphere, making up 10-20% of the planet's total mass and extending 10-20% of the distance to the core at its center. It consists of hydrogen, helium and methane, which gives the planet a bluish color. Descending deeper through it, we will notice how the atmosphere gradually thickens, slowly turning into a liquid and hot electrically conductive mantle.

Neptune's mantle is ten times heavier than our entire Earth and is rich in ammonia, water, and methane. It is really hot - the temperature can reach thousands of degrees - but traditionally this substance is called icy, and Neptune, like Uranus, is classified as an ice giant.

There is a hypothesis according to which, closer to the core, the pressure and temperature reach such a value that the methane “scatters” and is “compressed” into diamond crystals, which at a depth below 7000 km form an ocean of “diamond liquid”, which “rains” onto the planet’s core. Neptune's iron-nickel core is rich in silicates and is only slightly larger than Earth's, although the pressure in the central regions of the giant is much higher.

1. Upper atmosphere, upper clouds 2. Atmosphere consisting of hydrogen, helium and methane 3. Mantle consisting of water, ammonia and methane ice 4. Iron-nickel core

Naked Science

http://naked-science.ru/article/nakedscience/kak-ustroeny-planety

The solar system is part of the Milky Way, and it, in turn, is a spiral galaxy around the center of which the Sun rotates - the largest and heaviest object in the solar system, which is its heart. The Sun, in its system, has eight planets with their satellites, many asteroids, comets and an incredible number of meteoroids. The planets of the Solar System are divided into two types: the first is the terrestrial group, and the second is the giant planets.

The structure of the solar system has a significant impact not only on the planets, but also on their satellites, asteroids, comets and countless meteoric elements that also form part of it.

This includes Mercury, Venus, Earth and Mars. Their characteristic features are their small size and weight. As a rule, they contain metals and rocks, due to which they are distinguished by significant density. Terrestrial planets are located closer to the Sun than other cosmic bodies.

Giant planets

Jupiter, Saturn, Uranus and Neptune. They are characterized by large size and low density, due to their predominantly gas composition. Despite this, the giant planets have strong gravity and have a considerable number of satellites, Jupiter alone has 63 of them. These huge cosmic bodies are located at a distance from the Sun.

Asteroid rings

The first ring of asteroids is located on the border of two groups of celestial bodies - in the region of Mars and Jupiter and is considered the main one, and the second is the final element of the Solar system, it is located behind Pluto, in the recent past the ninth major planet, it is called the Kuiper belt. These asteroids are also called minor planets; approximately 10,000 asteroids in the main ring have been studied in our time; their number is estimated to be 300,000.

Dwarf planets

This is Pluto, which received this status in 2006, the brightest representative of the main asteroid ring - Ceres and the distant one - Eris. Dwarf planets are those that have a diameter of about 1000 km.

Comets

Objects of the Solar System consisting of ice and dust. They exist outside the second asteroid ring, practically in interstellar space, and only a few of them fall into the gravitational pull of the Sun, collapsing, forming a trail of vapor and dust.

Pattern of the Solar System

The main pattern is the movement of the planets. They move in one direction relative to the Sun, namely against the movement of the clock hands. Venus and Uranus, which moves almost on its side, as well as some satellites of the planets have a different direction of rotation. Cosmic bodies rotate in an orbit, the shape of which is close to a circle, however, the orbits of Mercury and Pluto have an elongated trajectory, and comets also move in such orbits.

Travel through the solar system