How to explain the relatively large compression of the giant planets. Interesting facts about the giant planets. Planets of the Solar System in order

Read: The group of giant planets includes Saturn, Jupiter, Neptune and Uranus. All of the listed planets (especially Jupiter) have enormous masses and sizes. For example, Jupiter exceeded the Earth in volume by almost one and a half thousand times, and in mass by more than three hundred times. The giant planet rotates quite quickly around its axis; It will take the huge Jupiter less than ten hours to complete 1 revolution. At the same time, the equatorial zone of the giant planet rotates faster than the polar one, that is, exactly where the linear speed of a point in its movement around its axis is maximum, the angular speed is also maximum. The result of rapid rotation is a huge compression of the giant planet (noticeable during visual observation). The difference between the polar and equatorial radii of the Earth was twenty-one kilometers, and for Jupiter it is equal to four thousand four hundred kilometers. The giant planet is located far from the Sun, and regardless of the nature of the season, it is always dominated by low temperatures. On Jupiter there is no change of season at all, because the axis of this planet is almost perpendicular to the plane of its orbit. The change of seasons also occurs on the planet Uranus in an original way, since the axis of this planet is inclined to the orbital planes at an angle of eight degrees. The giant planet is distinguished by a large number of satellites; by the middle of two thousand and one, twenty-eight of them had already been discovered at Jupiter, thirty at Saturn, twenty-one at Uranus, and eight only at Neptune. An excellent feature of a giant planet is the ring, which is open not only at Saturn, but also at Uranus, Neptune and Jupiter. An important feature of the construction of a giant planet is that such a planet does not have a solid surface. This idea is in excellent agreement with the small average frequencies of the giant planets. Accordingly, everything that can be seen on Saturn and Jupiter happens in the extended atmospheres of this planet. On Jupiter, even stripes that extend along the equator are visible in small telescopes. In the upper layer of the hydrogen-helium atmosphere of Jupiter, chemical compounds (for example, ammonia and methane), hydrocarbons (acetylene, ethane) and various compounds containing sulfur and phosphorus, which can color the parts of the atmosphere in red-brown and yellow colors, can be found as impurities . Thus, in terms of chemical composition, the giant planet differs sharply from the terrestrial planet. See also: General characteristics of the terrestrial planets
The planets that belong to the terrestrial group are the following: Venus, Mars, Earth, Mercury, Pluto - they all have small masses and sizes, their average density is several times higher than the density of water; they are able to slowly rotate around their own axes; they have a small number of satellites (Mars has two, Earth has only one...Giant planets
The photographs, which were transmitted from the American spacecraft Voyager and Pioneer, clearly show that in the atmosphere of Jupiter the gas is involved in more than a simple movement, accompanied by decay and the formation of vortices. It is believed that the observed Great Red Spot on Jupiter for about three hundred years in the form of an oval with semi-axes of fifteen and five thousand kilometers also represents a huge...Characteristics of the giant planets
Unlike a planet of terrestrial groups, endowed with a mantle, crust and core, Jupiter has gaseous hydrogen, which is part of the atmosphere, and can turn into a liquid and then into a solid phase. The appearance of these aggregate unnatural states of hydrogen is associated with an acute increase in pressure as it sinks into the depths...

1. Using reference books, fill out the table with the main physical characteristics of the giant planets.

80% H, 19% He, 1% CH 4

Number of satellites

Names of the largest satellites

Io, Europa, Ganymede, Callisto, Amalthea

Titan, Rhea, Iapetus, Dione, Tethys

Ariel, Oberon, Umbriel, Desdemona, Juliet

Triton, Nereid, Proteus, Larissa, Thalassa

After filling out the table, draw conclusions and indicate the similarities and differences between the giant planets.

Conclusions: These are gaseous bodies with powerful extended atmospheres, they rotate quickly around their axes, have many satellites, and they all have rings. Giant planets have neither a solid nor a liquid surface. The main components of all giant planets are helium and hydrogen.

2. Make a qualitative comparison of the properties of terrestrial planets and giant planets. Use the words: “high”, “low”, “large”, etc. In the conclusion, indicate the fundamental difference between the terrestrial planets and the giant planets.

Conclusion: Terrestrial planets have significantly smaller masses and sizes, but higher density, and do not have rings. They are located closer to the Sun and move faster in their orbits, but they rotate more slowly around their axis and are less compressed at the poles. They also have significantly fewer satellites.

3. Complete the sentences:

The peculiarity of the rotation of giant planets around their axis is that they rotatelayers: the layer of the planet near the equator rotates faster than other layers .

The presence of dense and extended atmospheres on Jupiter and Saturn is explained by the fact that during their formation they quickly reached such a mass in order to hold morehydrogen.

Saturn's moon Titan has a thick atmosphere consisting mainly ofnitrogen .

Giant planets have a low average density due to the fact that their atmospheres are mostlyhydrogen-helium compound.

The existence of rings has been discovered on the following giant planets:Jupiter, Saturn, Uranus and Neptune .

Jupiter emits significantly more thermal energy than it receives from the Sun. The reason for this can be considered the gradual compression of the planet( gravitational differentiation of the interior - the descent of heavier substances to the center of the planet) And the process of radioactive decay in its depths .

4. The sidereal period of Saturn’s rotation around the Sun is T = 29.5 years. What is the average distance from Saturn to the Sun?

5. What appearance will the rings of Saturn have for an observer located at the equator and at the poles of Saturn?

6. Complete the sentences concerning the internal structure of the giant planets.

The planets Jupiter and Saturn have between the central core and an extended atmosphereshell with metal properties .

Giant planets, like the Earth, havemagnetic field , the intensity of which is 12 times higher at Jupiter than at Earth; at Saturn it is close to the earth's;
Uranus is approximately equal to Earth's; Neptune has 3 times less than Earth.

Aurorae have been observed on the following giant planets:Jupiter, Saturn and Uranus .

Outer planets

In composition, structure and size, the outer planets of the solar system differ sharply from the inner planets of the terrestrial group. The outer planets have low density, which is determined by their gas composition. Moreover, the leading element of these planets is hydrogen and its compounds. By some estimates, Jupiter contains 78% hydrogen by weight, and Saturn 63%. Uranus and Neptune have higher average densities and probably have a lower proportion of hydrogen.

The spectra of the extended atmospheres of the outer planets show strong bands of methane, as well as bands of molecular hydrogen. In addition, weak ammonia bands are observed in the spectra of Jupiter and Saturn. However, on Uranus and Neptune, ammonia is in a frozen state, since the surface temperature of these planets is very low, about -210 ° C. At such temperatures, most gases turn into liquid and solid states. According to some indirect data, it can be assumed that the outer planets contain a lot of helium.

Thus, the large outer planets of the solar system are in many ways close to the composition of the Sun in their atomic elemental composition. They are composed predominantly of light components - H, He, CH 4, NH 3, H 2 O. The preservation of these substances in the composition of large planets is associated with the high masses of the planets themselves, as well as with the low temperatures of the outer edge regions of the solar nebula from which they originated.

The data presented above allows us to come to certainconclusions , directly related to questions of the origin of the solar system.

The planets of the solar system differ in their chemical composition. The inner planets are composed mainly of solids, while the outer planets are composed mainly of gases.

Among the inner planets there is also a difference in composition - the planets closest to the Sun are denser than those more distant.

The difference in the composition of the inner planets is apparently due to the same reasons as the difference in the composition of meteorites, i.e., denser planets contain more metal (iron-nickel) phase and less silicate. The maximum iron content is probably characteristic of Mercury, the minimum for the Moon, in which most of the iron is in silicates.

The difference in the composition of the planets indicates the chemical and physical fractionation of elements during the formation of the solar system. Fractionation was determined by different degrees of oxidation of the substance depending on the distance from the Sun.

The giant outer planets of the solar system arose from matter extremely close to the composition of the Sun, and fractionation processes during their formation were manifested to an insignificant extent.

Giant planets are the largest bodies in the Solar System

Giant planets - the largest bodies in the solar system after the Sun: Jupiter, Saturn, Uranus and Neptune. They are located beyond the Main Asteroid Belt and are therefore also called the “outer” planets.
Jupiter and Saturn are gas giants, meaning they consist mainly of gases that are in a solid state: hydrogen and helium.
But Uranus and Neptune were identified as ice giants, since in the thickness of the planets themselves, instead of metallic hydrogen, there is high-temperature ice.
Giant planets many times larger than the Earth, but compared to the Sun, they are very small:

Computer calculations have shown that giant planets play an important role in protecting the inner terrestrial planets from asteroids and comets.
Without these bodies in the solar system, our Earth would be hit by asteroids and comets hundreds of times more often!
How do giant planets protect us from the falls of uninvited guests?

You've probably heard about "space slalom", when automatic stations sent to distant objects in the solar system perform "gravitational maneuvers" near some planets. They approach them along a pre-calculated trajectory and, using the force of their gravity, accelerate even more, but do not fall onto the planet, but “shoot” as if from a sling with an even greater speed than at the entrance and continue their movement. This saves fuel, which would be needed for acceleration with engines alone.
In the same way, giant planets throw asteroids and comets outside the solar system, which fly past them, trying to break through to the inner planets, including the Earth. Jupiter, with its brothers, increases the speed of such an asteroid, pushes it out of its old orbit, it is forced to change its trajectory and flies into the cosmic abyss.
So, without giant planets , life on Earth would probably be impossible due to constant meteorite bombardment.

Well, now let’s briefly get acquainted with each of the giant planets.

Jupiter is the largest giant planet

First in order from the Sun, among the giant planets, is Jupiter. It is also the largest planet in the solar system.
Sometimes they say that Jupiter is a failed star. But to start its own process of nuclear reactions, Jupiter does not have enough mass, and quite a lot. Although, the mass is slowly growing due to the absorption of interplanetary matter - comets, meteorites, dust and solar wind. One of the options for the development of the Solar system shows that if this continues, then Jupiter may well become a star or a brown dwarf. And then our Solar system will become a double star system. By the way, double star systems are a common occurrence in the Cosmos around us. There are much fewer single stars, like our Sun.

There are calculations showing that Jupiter is already emitting more energy than it absorbs from the Sun. And if this is really the case, then nuclear reactions must already be taking place, otherwise there is simply nowhere for the energy to come from. And this is a sign of a star, not a planet...

Comparison of the sizes of Earth and Jupiter:

This image also shows the famous Great Red Spot, also called the “eye of Jupiter.” This is a giant vortex that has apparently existed for hundreds of years.

In 1989, the Galileo spacecraft was launched towards Jupiter. Over 8 years of work, he took unique photographs of the giant planet itself, the satellites of Jupiter, and also carried out many measurements.One can only guess what is going on in the atmosphere of Jupiter and in its depths. The Galileo probe, which descended 157 km into its atmosphere, survived for only 57 minutes, after which it was crushed by a pressure of 23 atmospheres. But he managed to report powerful thunderstorms and hurricane winds, and also transmitted data on composition and temperature.Ganymede, the largest moon of Jupiter, is also the largest of the planetary moons in the solar system.At the very beginning of the research, in 1994, Galileo observed the fall of Comet Shoemaker-Levy onto the surface of Jupiter and sent back images of this disaster. This event could not be observed from Earth - only residual phenomena that became visible as Jupiter rotated.

Saturn

Next comes an equally famous body of the solar system - the giant planet Saturn, which is known for its rings. Saturn's rings are made up of ice particles ranging in size from dust grains to fairly large chunks of ice. With an outer diameter of 282,000 kilometers, Saturn's rings are only about ONE kilometer thick. Therefore, when viewed from the side, Saturn's rings are not visible.
But, Saturn also has satellites. About 62 satellites of Saturn have now been discovered.
Saturn's largest moon is Titan, which is larger than the planet Mercury! But, it consists largely of frozen gas, that is, it is lighter than Mercury. If Titan is moved into Mercury's orbit, the icy gas will evaporate and Titan's size will greatly decrease.
Another interesting satellite of Saturn, Enceladus, attracts scientists because there is an ocean of liquid water under its icy surface. And if so, then life is possible in it, because the temperatures there are positive. Powerful water geysers have been discovered on Enceladus, shooting hundreds of kilometers high!

AND The Cassini research station has been in orbit around Saturn since 2004. During this time, a lot of data was collected about Saturn itself, its moons and rings.The automatic station "Huygens" was also landed on the surface of Titan, one of Saturn's moons. This was the first ever landing of a probe on the surface of a celestial body in the Outer Solar System.Despite its considerable size and mass, Saturn's density is approximately 9.1 times less than the density of Earth. Therefore, the acceleration of gravity at the equator is only 10.44 m/s². That is, having landed there, we would not have felt the increased gravity.

Uranus - ice giant

The atmosphere of Uranus consists of hydrogen and helium, and the interior is made of ice and solid rocks. Uranus appears to be a fairly calm planet, unlike the violent Jupiter, but vortices have still been noticed in its atmosphere. If Jupiter and Saturn are called gas giants, then Uranus and Neptune are ice giants, since in their depths there is no metallic hydrogen, but instead there is a lot of ice in various high-temperature states.
Uranus emits very little internal heat and is therefore the coldest of the planets in the solar system - a temperature of -224°C is recorded on it. Even on Neptune, which is further from the Sun, it is warmer.
Uranus has satellites, but they are not very large. The largest of them, Titania, is more than half the diameter of our Moon.

(No, I didn't forget to rotate the photo)

Unlike other planets in the solar system, Uranus seems to lie on its side - its own axis of rotation lies almost in the plane of rotation of Uranus around the Sun. Therefore, it turns to the Sun either with the South or North poles. That is, a sunny day at the pole lasts 42 years, and then gives way to 42 years of “polar night”, during which the opposite pole is illuminated.

This image was taken by the Hubble telescope in 2005. The rings of Uranus, the lightly colored south pole, and a bright cloud in the northern latitudes are visible.

It turns out that not only Saturn decorated himself with rings!

It is curious that all the planets bear the names of Roman gods. And only Uranus is named after a god from ancient Greek mythology.
The acceleration of gravity at the equator of Uranus is 0.886 g. That is, the gravity on this giant planet is even less than on Earth! And this despite its enormous mass... This is again due to the low density of the ice giant Uranus.

Spacecraft have flown past Uranus, taking pictures along the way, but detailed studies have not yet been carried out. True, NASA plans to send a research station to Uranus in the 2020s. The European Space Agency also has plans.

Neptune

Neptune is the farthest planet in the solar system, after Pluto was "demoted" to the "dwarf planets". Like the other giant planets, Neptune is much larger and heavier than Earth.

N
Septune, like Saturn, is an icy giant planet.

Neptune is quite far from the Sun and therefore became the first planet discovered through mathematical calculations, rather than through direct observations. The planet was visually discovered through a telescope on September 23, 1846 by astronomers at the Berlin Observatory, based on preliminary calculations by the French astronomer Le Verrier.It is curious that, judging by the drawings, Galileo Galilei observed Neptune long before this, back in 1612, with his first telescope! But... he did not recognize the planet in it, mistaking it for a fixed star. Therefore, Galileo is not considered the discoverer of the planet Neptune.

Despite its significant size and mass, Neptune's density is approximately 3.5 times less than the density of Earth. Therefore, at the equator the gravity is only 1.14 g, that is, almost the same as on Earth, like the two previous giant planets.

In our solar system today, scientists count eight planets. Scientists identify the four planets Jupiter, Saturn, Uranus and Neptune as a separate group of “gas giants”; together they make up 99% of the mass of matter that is in orbits belonging to the Sun. The article presents the most interesting facts about the giant planets.

1. The hallmark of Jupiter is the stripes on its surface., there are several theories about their origin. One theory states that the stripes appeared as a result of convection; this process involves heating and rising of some layers of the atmosphere, cooling and falling of others.
2. The Great Red Spot, located on Jupiter, an atmospheric phenomenon similar to a storm, was discovered back in the 17th century. Lightning discharges have been discovered on the planet that are three times more powerful than those on Earth. The speed of wind gusts exceeds 600 km/h, and their formation is due to the release of heat from the bowels of the gas giant.

   

3. Astronomers now know about the existence of 67 satellites of the planet Jupiter. The largest - Io, Europa, Ganymede and Callisto were discovered in the 17th century by Galileo Galilei.

   

4. If the name of Jupiter's satellite ends in "e", for example, Karma, Pasipha, this means that they rotate in the opposite direction relative to the axial rotation of the gas giant.

   

5. Jupiter has the highest rotation speed around its axis in the solar system, the planet makes a full revolution in 9 hours 50 minutes. There is no change of seasons on Jupiter, this is due to the slight tilt of the axis around which the “giant” rotates, just over 3 degrees; for comparison, the Earth has 23.5.

   

6. At the north pole of Saturn there is a hexagon formed by clouds, and its shape tends to be correct, the reasons for its occurrence are unknown. At both poles, scientists have discovered oval and spiral-shaped auroras.

   

7. To make a full revolution around the Sun, Saturn takes almost 30 Earth years, but the change of day and night occurs only ~10 times during this time. Different parts of this gas giant rotate at different speeds, “zone 1” has a rotation interval of 10 hours 14 minutes, “zone 2” - 10 hours, 34 minutes, “zone 3” - 10 hours 39 minutes.

   

8. Of the entire group of giant planets, Saturn has the most noticeable rings; they consist of ice particles. The rings of Saturn are very thin, less than 1 kilometer, in 1921 the whole world decided that the rings had disappeared, this happened because the rings became at a certain angle and the instruments of that time did not allow them to be seen.

   

9. Uranus was discovered in 1781 by astronomer William Herschel and became the first planet discovered in the modern world. Initially, this Gas giant was mistaken for a star, and later for a comet. The planet's first name was "George", in honor of George III, who ruled England at the time of its discovery.

   

10. The atmosphere is 98% hydrogen and helium, but unlike the other two giant planets, Uranus and Neptune contain large amounts of ice in their depths. Atmospheric phenomena on Uranus are extremely insignificant, this is due to the low temperatures on the planet; it is the coldest planet in our solar system.

    

11. Uranus' rotation axis is offset at an angle of almost 98 degrees relative to its rotation around the Sun, as a result of which different parts alternately face the Sun. Day and night alternate at the poles every 42 Earth years.

    

12. Uranus became the second planet to have a ring system discovered. Scientists are inclined to believe that the rings did not form together with Uranus, but later, during the destruction of some of its satellites. There are 13 rings, the inner rings are gray, the middle ones are red, and the two outer ones are blue.

    

13. In terms of the composition of its atmosphere and body, Neptune is most similar to Uranus, but its blue color is given by the significant methane content in the atmosphere. Scientists suggest that this planet has the fastest winds in the entire solar system, up to 2100 km/h. The estimated temperature on the surface is -220 degrees, and in the interior of the planet 7000–7100.

    

14. From Earth, Neptune can only be observed once during its year(on opening day September 26, 1846, later in 2011). In 2011, exactly a year has passed on Neptune since its discovery; it was 164.79 Earth years.

    

15. Neptune's largest moon, Triton, orbits the planet in the opposite direction of its rotation. Triton moves in a spiral and will be destroyed in about 10 million years after passing the Roche limit.

    

Space has long attracted people's attention. Astronomers began studying the planets of the Solar System back in the Middle Ages, examining them through primitive telescopes. But a thorough classification and description of the structural features and movements of celestial bodies became possible only in the 20th century. With the advent of powerful equipment, state-of-the-art observatories and spacecraft, several previously unknown objects were discovered. Now every schoolchild can list all the planets of the solar system in order. A space probe has landed on almost all of them, and so far man has only visited the Moon.

What is the Solar System

The Universe is huge and includes many galaxies. Our Solar System is part of a galaxy containing more than 100 billion stars. But there are very few that are like the Sun. Basically, they are all red dwarfs, which are smaller in size and do not shine as brightly. Scientists have suggested that the solar system was formed after the emergence of the Sun. Its huge field of attraction captured a gas-dust cloud, from which, as a result of gradual cooling, particles of solid matter formed. Over time, celestial bodies were formed from them. It is believed that the Sun is now in the middle of its life path, so it, as well as all the celestial bodies dependent on it, will exist for several more billions of years. Near space has been studied by astronomers for a long time, and any person knows what planets of the solar system exist. Photos of them taken from space satellites can be found on the pages of various information resources devoted to this topic. All celestial bodies are held by the strong gravitational field of the Sun, which makes up more than 99% of the volume of the Solar System. Large celestial bodies rotate around the star and around its axis in one direction and in one plane, which is called the ecliptic plane.

Planets of the Solar System in order

In modern astronomy, it is customary to consider celestial bodies starting from the Sun. In the 20th century, a classification was created that includes 9 planets of the solar system. But recent space exploration and new discoveries have pushed scientists to revise many provisions in astronomy. And in 2006, at an international congress, due to its small size (a dwarf with a diameter not exceeding three thousand km), Pluto was excluded from the number of classical planets, and there were eight of them left. Now the structure of our solar system has taken on a symmetrical, slender appearance. It includes the four terrestrial planets: Mercury, Venus, Earth and Mars, then comes the asteroid belt, followed by the four giant planets: Jupiter, Saturn, Uranus and Neptune. On the outskirts of the solar system there is also a space that scientists call the Kuiper Belt. This is where Pluto is located. These places are still little studied due to their remoteness from the Sun.

Features of the terrestrial planets

What allows us to classify these celestial bodies as one group? Let us list the main characteristics of the inner planets:

• relatively small size;
• hard surface, high density and similar composition (oxygen, silicon, aluminum, iron, magnesium and other heavy elements);
• presence of atmosphere;
• identical structure: a core of iron with nickel impurities, a mantle consisting of silicates, and a crust of silicate rocks (except for Mercury - it has no crust);
• a small number of satellites - only 3 for four planets;
• rather weak magnetic field.

Features of the giant planets

As for the outer planets, or gas giants, they have the following similar characteristics:

• large sizes and weights;
• they do not have a solid surface and consist of gases, mainly helium and hydrogen (therefore they are also called gas giants);
• liquid core consisting of metallic hydrogen;
• high rotation speed;
• a strong magnetic field, which explains the unusual nature of many processes occurring on them;
• there are 98 satellites in this group, most of which belong to Jupiter;
• The most characteristic feature of gas giants is the presence of rings. All four planets have them, although they are not always noticeable.

The first planet is Mercury

It is located closest to the Sun. Therefore, from its surface the star appears three times larger than from the Earth. This also explains the strong temperature changes: from -180 to +430 degrees. Mercury moves very quickly in its orbit. Maybe that’s why it got such a name, because in Greek mythology Mercury is the messenger of the gods. There is practically no atmosphere here and the sky is always black, but the Sun shines very brightly. However, there are places at the poles where its rays never hit. This phenomenon can be explained by the tilt of the rotation axis. No water was found on the surface. This circumstance, as well as the abnormally high daytime temperature (as well as the low nighttime temperature) fully explain the fact of the absence of life on the planet.

Venus

If you study the planets of the solar system in order, then Venus comes second. People could observe it in the sky back in ancient times, but since it was shown only in the morning and evening, it was believed that these were 2 different objects. By the way, our Slavic ancestors called it Mertsana. It is the third brightest object in our solar system. People used to call it the morning and evening star, because it is best visible before sunrise and sunset. Venus and Earth are very similar in structure, composition, size and gravity. This planet moves very slowly around its axis, making a full revolution in 243.02 Earth days. Of course, conditions on Venus are very different from those on Earth. It is twice as close to the Sun, so it is very hot there. The high temperature is also explained by the fact that thick clouds of sulfuric acid and an atmosphere of carbon dioxide create a greenhouse effect on the planet. In addition, the pressure at the surface is 95 times greater than on Earth. Therefore, the first ship that visited Venus in the 70s of the 20th century stayed there for no more than an hour. Another peculiarity of the planet is that it rotates in the opposite direction compared to most planets. Astronomers still know nothing more about this celestial object.

Third planet from the Sun

The only place in the Solar System, and indeed in the entire Universe known to astronomers, where life exists is Earth. In the terrestrial group it has the largest size. What else are her

1. The highest gravity among the terrestrial planets.
2. Very strong magnetic field.
3. High density.
4. It is the only one among all the planets that has a hydrosphere, which contributed to the formation of life.
5. It has the largest satellite compared to its size, which stabilizes its tilt relative to the Sun and influences natural processes.

The planet Mars

This is one of the smallest planets in our Galaxy. If we consider the planets of the solar system in order, then Mars is the fourth from the Sun. Its atmosphere is very rarefied, and the pressure on the surface is almost 200 times less than on Earth. For the same reason, very strong temperature changes are observed. The planet Mars has been little studied, although it has long attracted the attention of people. According to scientists, this is the only celestial body on which life could exist. After all, in the past there was water on the surface of the planet. This conclusion can be drawn from the fact that there are large ice caps at the poles, and the surface is covered with many grooves, which could be dried up river beds. In addition, there are some minerals on Mars that can only be formed in the presence of water. Another feature of the fourth planet is the presence of two satellites. What makes them unusual is that Phobos gradually slows down its rotation and approaches the planet, while Deimos, on the contrary, moves away.

What is Jupiter famous for?

The fifth planet is the largest. The volume of Jupiter would fit 1300 Earths, and its mass is 317 times that of Earth. Like all gas giants, its structure is hydrogen-helium, reminiscent of the composition of stars. Jupiter is the most interesting planet, which has many characteristic features:

• it is the third brightest celestial body after the Moon and Venus;
• Jupiter has the strongest magnetic field of any planet;
• it completes a full revolution around its axis in just 10 Earth hours - faster than other planets;
• An interesting feature of Jupiter is the large red spot - this is how an atmospheric vortex rotating counterclockwise is visible from Earth;
• like all giant planets, it has rings, although not as bright as Saturn’s;
• this planet has the largest number of satellites. He has 63 of them. The most famous are Europa, where water was found, Ganymede - the largest satellite of the planet Jupiter, as well as Io and Calisto;
• Another feature of the planet is that in the shadow the surface temperature is higher than in places illuminated by the Sun.

Planet Saturn

It is the second largest gas giant, also named after the ancient god. It is composed of hydrogen and helium, but traces of methane, ammonia and water have been found on its surface. Scientists have found that Saturn is the rarest planet. Its density is less than that of water. This gas giant rotates very quickly - it makes one revolution in 10 Earth hours, as a result of which the planet is flattened from the sides. Huge speeds on Saturn and the wind - up to 2000 kilometers per hour. This is faster than the speed of sound. Saturn has another distinctive feature - it holds 60 satellites in its field of gravity. The largest of them, Titan, is the second largest in the entire solar system. The uniqueness of this object lies in the fact that by examining its surface, scientists for the first time discovered a celestial body with conditions similar to those that existed on Earth about 4 billion years ago. But the most important feature of Saturn is the presence of bright rings. They circle the planet around the equator and reflect more light than the planet itself. Four is the most amazing phenomenon in the solar system. What's unusual is that the inner rings move faster than the outer rings.

- Uranus

So, we continue to consider the planets of the solar system in order. The seventh planet from the Sun is Uranus. It is the coldest of all - the temperature drops to -224 °C. In addition, scientists did not find metallic hydrogen in its composition, but found modified ice. Therefore, Uranus is classified as a separate category of ice giants. An amazing feature of this celestial body is that it rotates while lying on its side. The change of seasons on the planet is also unusual: winter reigns there for as many as 42 Earth years, and the Sun does not appear at all; summer also lasts 42 years, and the Sun does not set during this time. In spring and autumn, the star appears every 9 hours. Like all giant planets, Uranus has rings and many satellites. As many as 13 rings revolve around it, but they are not as bright as those of Saturn, and the planet holds only 27 satellites. If we compare Uranus with the Earth, then it is 4 times larger than it, 14 times heavier and is located at a distance from the Sun of 19 times the path to the star from our planet.

Neptune: the invisible planet

After Pluto was excluded from the number of planets, Neptune became the last from the Sun in the system. It is located 30 times further from the star than the Earth, and is not visible from our planet even with a telescope. Scientists discovered it, so to speak, by accident: observing the peculiarities of the movement of the planets closest to it and their satellites, they concluded that there must be another large celestial body beyond the orbit of Uranus. After discovery and research, interesting features of this planet were revealed:

• due to the presence of a large amount of methane in the atmosphere, the color of the planet from space appears blue-green;
• Neptune's orbit is almost perfectly circular;
• the planet rotates very slowly - it makes one circle every 165 years;
• Neptune is 4 times larger than Earth and 17 times heavier, but the force of gravity is almost the same as on our planet;
• the largest of the 13 satellites of this giant is Triton. It is always turned to the planet with one side and slowly approaches it. Based on these signs, scientists suggested that it was captured by the gravity of Neptune.

There are about one hundred billion planets in the entire Milky Way galaxy. So far, scientists cannot study even some of them. But the number of planets in the solar system is known to almost all people on Earth. True, in the 21st century, interest in astronomy has faded a little, but even children know the names of the planets of the solar system.

Lecture: Solar system: terrestrial planets and giant planets, small bodies of the solar system

The solar system consists of various kinds of bodies. The main one, of course, is the sun. But if you do not take it into account, the planets are considered the main elements of the solar system. They are the second most important elements after the sun. The solar system itself bears this name due to the fact that the sun plays a key role here, since all the planets revolve around the sun.

Terrestrial planets

Currently, there are two groups of planets in the Solar System. The first group is the terrestrial planets. These include Mercury, Venus, Earth, and also Mars. In this list, they are all listed based on the distance from the Sun to each of these planets. They got their name due to the fact that their properties are somewhat reminiscent of the characteristics of planet Earth. All terrestrial planets have a solid surface. The peculiarity of each of these planets is that they all rotate differently around their own axis. For example, for the Earth, one complete rotation occurs within a day, that is, 24 hours, while for Venus, a complete rotation occurs in 243 Earth days.

Each of the terrestrial planets has its own atmosphere. It varies in density and composition, but it definitely exists. For example, in Venus it is quite dense, while in Mercury it is almost invisible. In fact, at the moment there is an opinion that Mercury has no atmosphere at all, however, in fact, this is not the case. All atmospheres of terrestrial planets consist of substances whose molecules are relatively heavy. For example, the atmosphere of Earth, Venus and Mars consists of carbon dioxide and water vapor. In turn, Mercury's atmosphere consists mainly of helium.

Apart from the atmosphere, all terrestrial planets have approximately the same chemical composition. In particular, they consist predominantly of silicon compounds, as well as iron. However, these planets also contain other elements, but their number is not so large.

A feature of the terrestrial planets is that at their center there is a core of varying mass. At the same time, all nuclei are in a liquid state - the only exception is Venus.

Each of the terrestrial planets has its own magnetic fields. At the same time, on Venus their influence is almost imperceptible, while on Earth, Mercury and Mars they are quite noticeable. As for the Earth, its magnetic fields do not stand in one place, but move. And although their speed is extremely low compared to human concepts, scientists suggest that the movement of the fields may subsequently lead to a change in the magnetic belts.

Another feature of the terrestrial planets is that they have virtually no natural satellites. In particular, to date they have been discovered only near the Earth and Mars.

Giant planets

The second group of planets is called the “giant planets”. These include Jupiter, Saturn, Uranus and Neptune. Their mass significantly exceeds the mass of the terrestrial planets.

The lightest giant today is Uranus, however, its mass exceeds the mass of the earth

approximately 14 and a half times. And the heaviest planet in the solar system (with the exception of the Sun) is Jupiter.

None of the giant planets actually have their own surface, since they are all in a gaseous state. The gases that make up these planets, as they approach the center or equator, as it is called, turn into a liquid state. In this regard, one can notice the difference in the characteristics of the rotation of the giant planets around their own axis. It should be noted that the duration of a full revolution is a maximum of 18 hours. Meanwhile, each layer of the planet rotates around its axis at different speeds. This feature is due to the fact that giant planets are not solid. In this regard, their individual parts seem to be unrelated to each other.

At the center of all giant planets there is a small solid core. Most likely, one of the main substances of these planets is hydrogen, which has metallic characteristics. Thanks to this, it has now been proven that giant planets have their own magnetic field. However, in science at the moment there is very little convincing evidence and a lot of contradictions that could characterize the giant planets.

Their distinctive feature is that such planets have many natural satellites, as well as rings. In this case, rings are small clusters of particles that rotate directly around the planet and collect various types of small particles flying by.

At the moment, only 9 large planets are officially known to science. However, the terrestrial planets and giant planets include only eight. The ninth planet, which is Pluto, does not fit into any of the listed groups, since it is located at a very far distance from the Sun and is practically not studied. The only thing that can be said about Pluto is that its state is close to solid. There is currently speculation that Pluto is not a planet at all. This assumption has existed for more than 20 years, but the decision to exclude Pluto from the list of planets has not yet been made.

Small bodies of the solar system

In addition to the planets, in the Solar System there are a lot of all kinds of bodies that are relatively small in weight, which are called asteroids, comets, small planets, and so on. In general, these celestial bodies are included in the group of small celestial bodies. They differ from planets in that they are solid, relatively small in size, and can move around the Sun not only in the forward direction, but also in the opposite direction. Their sizes are much smaller compared to any of the currently discovered planets. Losing cosmic gravity, small celestial bodies of the solar system fall into the upper layers of the earth's atmosphere, where they burn up or fall in the form of meteorites. The change in the state of bodies orbiting other planets has not yet been studied.