Solar system definition. The planets of the solar system and their arrangement in order

This is the closest planet to the Sun, so the Sun shines on Mercury and heats 7 times stronger than on Earth. On the day side of Mercury, it is terribly hot, there is eternal hell. Measurements show that the temperature there rises to 400 degrees above zero. But on the night side there should always be a strong frost, which probably reaches 200 degrees below zero. So, Mercury is the kingdom of deserts. One half of it is a hot stone desert, the other half is an icy desert, perhaps covered with frozen gases. The composition of the extremely rarefied atmosphere of Mercury includes: Ar, Ne, He. The surface of Mercury is similar in appearance to that of the moon. When Mercury is far enough from the Sun, it can be seen standing low on the horizon. Mercury is never visible dark sky. It is best to observe it in the evening sky or before dawn. Mercury has no satellites. 80% of the mass of Mercury is contained in its core, which consists mainly of iron. The pressure at the surface of the planet is approximately 500 billion times less than that at the surface of the Earth. It also turned out that Mercury has a weak magnetic field, the strength of which is only 0.7% of that of the earth. Mercury belongs to the terrestrial planets. In Roman mythology, the god of trade.

Venus


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

Earth .

.
is the third planet from the Sun. The speed of the Earth's circulation in an elliptical orbit around the Sun is - 29.765 km / s. The inclination of the earth's axis to the plane of the ecliptic is 66 o 33 "22". The Earth has a natural satellite -. The Earth has magnetic and electric fields. The Earth was formed 4.7 billion years ago from gas-dust matter scattered in the protosolar system. 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, temperature 5000-6000 o C. Most of the surface is occupied by the World Ocean (361.1 million km 2; 70.8%), land is 149.1 million km 2 and forms six continents and islands. It rises above the world ocean level by an average of 875 meters (the highest height is 8848 meters - the city of Chomolungma).Mountains occupy 30% of the land, deserts cover about 20% of the land surface, savannahs and light forests - about 20%, forests - about 30%, glaciers - 10%. Average depth ocean about 3800 meters, the largest - 11022 meters (Marian Trench in pacific ocean), the volume of water is 1370 million km 3, the average salinity is 35 g / l. The atmosphere of the Earth, the total mass of which is 5.15 * 10 15 tons, consists of air - a mixture of mainly nitrogen (78.1%) and oxygen (21%), the rest is water vapor, carbon dioxide, noble and other gases. About 3-3.5 billion years ago, as a result of the natural evolution of matter, life arose on Earth, and the development of the biosphere began.

Mars .

.
the fourth planet from the Sun, similar to Earth, but smaller and colder. Mars has deep canyons, giant volcanoes, and vast deserts. Around the Red Planet, as Mars is also called, two small moons fly: Phobos and Deimos. Mars is the planet next to the Earth, if you count from the Sun, and the only space world, apart from the Moon, that can already be reached with modern rockets. For astronauts, this 4-year journey could be the next frontier in exploration. outer space. Near the equator of Mars, in the region called Tharsis, there are volcanoes of colossal proportions. Tarsis is the name that astronomers gave to a hill that has 400 km. wide and about 10 km. in height. There are four volcanoes on this plateau, each of which is simply a giant in comparison with any terrestrial volcano. The most grandiose volcano of Tarsis, Mount Olympus, rises above the surrounding area for 27 km. About two-thirds of the surface of Mars is a mountainous area with a large number of impact craters and surrounded by debris of hard rocks. Near the volcanoes of Tharsis snakes a vast system of canyons about a quarter of the equator long. The Mariner Valley is 600 km wide, and its depth is such that Mount Everest would sink entirely to its bottom. Sheer cliffs rise thousands of meters, from the bottom of the valley to the plateau above. In ancient times, there was a lot of water on Mars, on the surface of this planet flowed big rivers. Ice caps lie at the South and North Poles of Mars. But this ice does not consist of water, but of frozen atmospheric carbon dioxide (it freezes at a temperature of -100 o C). Scientists believe that surface water are stored in the form of ice blocks buried in the ground, especially in the polar regions. Atmospheric composition: CO 2 (95%), N 2 (2.5%), Ar (1.5 - 2%), CO (0.06%), H 2 O (up to 0.1%); pressure near the surface is 5-7 hPa. In total, about 30 interplanetary space stations were sent to Mars.

Jupiter - the largest planet.

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

Saturn .

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

Uranus .

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

Neptune .

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

The planets in the solar system, as you can see from the descriptions, are all different from each other. Scientists also find planets around other stars, they are called exoplanets.

Sources:
www.kosmos19.narod.ru
www.ggreen.chat.ru
http://en.wikipedia.org

Until recently, astronomers believed that such a concept as a planet refers exclusively to the solar system. Everything that is outside it is unexplored cosmic bodies, most often stars are very large scale. But, as it turned out later, the planets, like peas, are scattered throughout the universe. They differ in their geological and chemical composition, may or may not have an atmosphere, and it all depends on the interaction with the nearest star. The arrangement of the planets in our solar system is unique. It is this factor that is fundamental for the conditions that have formed on each individual space object.

Our space house and its features

In the center of the solar system is the star of the same name, which is included in the category of yellow dwarfs. Its magnetic field is enough to hold nine planets around its axis. various sizes. Among them there are dwarf stony cosmic bodies, immense gas giants that reach almost the parameters of the star itself, and objects of the "middle" class, which include the Earth. The positions of the planets in the solar system do not occur in ascending or descending order. We can say that with respect to the parameters of each individual astronomical body, their arrangement is chaotic, that is, the large alternates with the small.

SS structure

To consider the location of the planets in our system, it is necessary to take the Sun as a reference point. This star is in the center of the SS, and it is her magnetic fields correct the orbits and movements of all surrounding space bodies. Nine planets revolve around the Sun, as well as an asteroid ring that lies between Mars and Jupiter, and the Kuiper Belt, located outside of Pluto. In these intervals, individual dwarf planets are also distinguished, which are sometimes attributed to the main units of the system. Other astronomers believe that all these objects are nothing more than large asteroids, on which, under no circumstances, life can arise. They attribute Pluto itself to this category, leaving only 8 planetary units in our system.

The order of the planets

So, we will list all the planets, starting with the one closest to the Sun. In the first place are Mercury, Venus, then Earth and Mars. After the Red Planet, a ring of asteroids passes, behind which a parade of giants consisting of gases begins. These are Jupiter, Saturn, Uranus and Neptune. The list is completed by the dwarf and icy Pluto, with its no less cold and black satellite Charon. As we said above, several more dwarf space units are distinguished in the system. The location of dwarf planets in this category coincides with the Kuiper belts and asteroids. Ceres is in an asteroid ring. Makemake, Haumea and Eris are in the Kuiper belt.

terrestrial planets

AT this category space bodies are included, which in their composition and parameters have much in common with our home planet. Their bowels are also filled with metals and stone, either a full-fledged atmosphere is formed around the surface, or a haze that resembles it. The location of the terrestrial planets is easy to remember, because these are the first four objects that are directly next to the Sun - Mercury, Venus, Earth and Mars. characteristic features are not big sizes, as well as a long period rotation around its axis. Also, of all the terrestrial planets, only the Earth itself and Mars have satellites.

Giants made of gases and hot metals

The location of the planets of the solar system, which are called gas giants, is the most distant from the main star. They are located behind the asteroid ring and stretch almost to the Kuiper belt. There are four giants in total - Jupiter, Saturn, Uranus and Neptune. Each of these planets consists of hydrogen and helium, and in the region of the core there are metals heated to a liquid state. All four giants are characterized by an incredibly strong gravitational field. Due to this, they attract numerous satellites to themselves, which form almost entire asteroid systems around them. SS gas balls rotate very quickly, therefore whirlwinds and hurricanes often occur on them. But, despite all these similarities, it is worth remembering that each of the giants is unique in its composition, size, and gravity.

dwarf planets

Since we have already considered in detail the location of the planets from the Sun, we know that Pluto is the farthest, and its orbit is the most gigantic in the SS. It is he who is the most important representative of dwarfs, and only he from this group is the most studied. Dwarfs are those cosmic bodies that are too small for planets, but also large for asteroids. Their structure can be comparable to Mars or Earth, or it can be just rocky, like any asteroid. Above we have listed the most prominent representatives of this group are Ceres, Eris, Makemake, Haumea. In fact, dwarfs are found not only in the two SS asteroid belts. Often they are called satellites of gas giants, which were attracted to them due to the huge

Our solar system consists of the Sun, the planets revolving around it, and smaller celestial bodies. All of these are mysterious and amazing, because they are still not fully understood. Below will be indicated the sizes of the planets of the solar system in ascending order, and briefly talk about the planets themselves.

There is a well-known list of planets in which they are listed in order of their distance from the Sun:

Pluto used to be in last place, but in 2006 it lost its status as a planet, as larger ones were found farther away. celestial bodies. These planets are divided into stone (inner) and giant planets.

Brief information about the stone planets

The inner (stone) planets include those bodies that are located inside the asteroid belt that separates Mars and Jupiter. They got their name "stone" because they consist of various hard rocks, minerals and metals. They are united by a small number or even the absence of satellites and rings (like Saturn). On the surface of the stone planets there are volcanoes, depressions and craters formed as a result of the fall of other cosmic bodies.

But if we compare their sizes and arrange them in ascending order, the list will look like this:

Brief information about the giant planets

The giant planets are located beyond the asteroid belt and therefore they are also called outer. They consist of very light gases - hydrogen and helium. These include:

But if you make a list by the size of the planets in the solar system in ascending order, then the order changes:

A little information about the planets

In modern scientific understanding, a planet means a celestial body that revolves around the Sun and has enough mass for its own gravity. Thus, there are 8 planets in our system, and, importantly, these bodies are not similar to each other: each has its own unique differences, as in appearance, and in the very components of the planet.

- This is the closest planet to the Sun and the smallest among the rest. She weighs 20 times smaller than Earth! But, despite this, it has a sufficiently high density, which allows us to conclude that there are a lot of metals in its depths. Due to its close proximity to the Sun, Mercury is subject to sharp temperature changes: at night it is very cold, during the day the temperature rises sharply.

- This is the next planet close to the Sun, in many ways similar to the Earth. It has a more powerful atmosphere than the Earth, and is considered a very hot planet (its temperature is above 500 C).

is a unique planet due to its hydrosphere, and the presence of life on it led to the appearance of oxygen in its atmosphere. Most of the surface is covered with water, and the rest is occupied by the continents. Unique feature are also tectonic plates that move, albeit very slowly, which leads to a change in the landscape. The Earth has one satellite - the Moon.

Also known as the "Red Planet". It gets its fiery red color due to the large amount of iron oxides. Mars has a very rarefied atmosphere and much lower atmospheric pressure than Earth. Mars has two satellites - Deimos and Phobos.

- this is a real giant among the planets of the solar system. Its weight is 2.5 times the weight of all the planets combined. The surface of the planet is made up of helium and hydrogen and is similar in many ways to the sun. Therefore, it is not surprising that there is no life on this planet - no water and no solid surface. But Jupiter has big number satellites: on this moment known 67.

- this planet is famous for the presence of rings, consisting of ice and dust, revolving around the planet. With its atmosphere, it resembles that of Jupiter, and is slightly smaller in size than this giant planet. In terms of the number of satellites, Saturn is also slightly behind - it knows 62 of them. The largest satellite, Titan, is larger than Mercury.

- the lightest planet among the outer ones. Its atmosphere is the coldest in the entire system (minus 224 degrees), it has a magnetosphere and 27 satellites. Uranus is made up of hydrogen and helium, and ammonia ice and methane have also been noted. Due to the fact that Uranus has a large axial tilt, it seems that the planet is rolling rather than rotating.

- despite being smaller than y, it is heavier than it and exceeds the mass of the Earth. This is the only planet that was found through mathematical calculations, and not through astronomical observations. On this planet, the most strong winds in the solar system. Neptune has 14 moons, one of which, Triton, is the only one that rotates backwards.

It is very difficult to imagine all the scales of the solar system within the studied planets. It seems to people that the Earth is a huge planet, and, in comparison with other celestial bodies, it is. But if you put giant planets next to it, then the Earth already takes on tiny sizes. Of course, next to the Sun, all celestial bodies seem small, so to represent all the planets in their full scale is a difficult task.

The most famous classification of the planets is their distance from the Sun. But a listing that takes into account the sizes of the planets of the solar system in ascending order will also be correct. The list will be presented as follows:

As you can see, the order has not changed much: the first lines are the inner planets, and the first place is occupied by Mercury, and the other positions are the outer planets. In fact, it doesn’t matter at all in what order the planets are located, from this they will not become less mysterious and beautiful.

Previously, a planet was called any cosmic body, orbiting a star, emitting light that the star reflects, and larger than an asteroid. Also in Ancient Greece they talked about 7 planets as luminous bodies that move across the sky against the background of stars. These are Mercury, Sun, Venus, Mars, Moon, Jupiter, Saturn. Note that the Sun, which is a star, and the Moon, a satellite of our Earth, are indicated here. The earth is not included in this list because the Greeks considered it to be the center of everything.

In the 15th century, Copernicus figured out that the center of the system was the sun, not the earth. He laid out his statements in the work "On the Revolution of the Celestial Spheres". The moon and the sun were removed from the list, and the planet Earth was included. When telescopes were invented, three more planets were discovered. Uranus in 1781, Neptune in 1846, Pluto in 1930, which, by the way, is no longer considered a planet.

At the moment, researchers are giving a new meaning to the word "planet", namely: it is a celestial body that satisfies 4 conditions:

• The body must revolve around the star.
• Have a spherical or approximate shape, that is, the body must have sufficient gravity.
• It doesn't have to be a star.
• The celestial body should not have other large bodies in the vicinity of the orbit.

A star is a body that emits light and has a powerful source of energy.

Planets in the solar system

The solar system includes the planets and other objects that revolve around the sun. 4.5 billion years ago, clumps of stellar matter clouds began to form in the Galaxy. The gases heated up and radiated heat. As a result of the increase in temperature and density, nuclear reactions began, hydrogen turned into helium. So there was a powerful source of energy - the Sun. This process took tens of millions of years. Planets with satellites were created. The entire formation of the solar system ended about 4 billion years ago.

To date, the solar system includes 8 planets, which are divided into two groups. The first is the terrestrial group, the second is the gas giants. The terrestrial planets - Venus, Mercury, Mars and Earth - are composed of silicates and metals. The gas giants - Saturn, Jupiter, Neptune and Uranus - are made up of hydrogen and helium. At the planets different sizes both in comparison between the two groups and among themselves. Accordingly, the giants are much larger and more massive than the terrestrial planets.

Mercury is closest to the Sun, next is Neptune. Before characterizing the planets of the solar system, you need to talk about its main object - the Sun. This is a star, thanks to which all living and non-living things in the system began to exist. The Sun is a spherical, plasma, hot ball. A large number of space objects revolve around it - satellites, planets, meteorites, asteroids and cosmic dust. This star appeared about 5 billion years ago. Its mass is 300 thousand times greater than the mass of our planet. The temperature of the core is 13 million degrees Kelvin, and on the surface - 5 thousand degrees Kelvin (4727 degrees Celsius). In the galaxy milky way The sun is one of the largest and bright stars. The distance from the Sun to the center of the Galaxy is 26,000 light years. The sun makes a complete revolution around the galactic center in 230-250 million years.

Mercury

It is closest to the Sun and is the smallest planet in the solar system. The planet has no satellites. There are many craters on the surface of Mercury, which were formed by many meteorites that fell on the planet more than 3 billion years ago. Their diameter is varied - from a couple of meters to 1000 kilometers. The planet's atmosphere is mostly helium and blown by the Sun's wind. The temperature can reach +440 degrees Celsius. The planet makes a revolution around the Sun in 88 Earth days. A day on the planet equals 176 Earth hours.

Venus

Venus is the second planet from the Sun. Its dimensions are close to the dimensions of the Earth. The planet has no satellites. The atmosphere is carbon dioxide mixed with nitrogen and oxygen. Air pressure is 90 atmospheres, which is 35 times greater than on Earth. Venus is called the hottest planet because the dense atmosphere, carbon dioxide, the proximity of the Sun and Greenhouse effect form very high temperatures on the surface of the planet. It can reach 460 degrees Celsius. Venus can be seen from the Earth's surface. It is the brightest space object after the Moon and the Sun.

Earth

The only planet adapted for life. Maybe it exists on other planets, but so far no one can say with certainty. In its group, it is the largest in terms of mass, density and size. Its age is over 4 billion years. Life here originated more than 3 billion years ago. The Earth's satellite is the Moon. The atmosphere on the planet is fundamentally different from others. Most of it is made up of nitrogen. It also includes carbon dioxide, oxygen, water vapor and argon. The ozone layer and the magnetic field reduce the level of solar and cosmic radiation. Due to the content of carbon dioxide in the Earth's atmosphere, a greenhouse effect is formed on the planet. Without it, the temperature on the Earth's surface would be 40 degrees less. Islands and continents occupy 29% of the planet's surface, and the rest is the oceans.

Mars

It is also called the "red planet" due to the presence of a large amount of iron oxide in the soil. Mars is the seventh largest planet in the solar system. Two satellites fly near the planet - Deimos and Phobos. Due to the too rarefied atmosphere and the far distance from the Sun, the average annual temperature of the planet is minus 60 degrees. At some points during the day, temperature drops can reach 40 degrees. The presence of volcanoes and craters, deserts and valleys, ice polar caps distinguishes Mars from other planets of the solar system. Also here is the most high mountain – dormant volcano Olympus, reaching a height of 27 kilometers. The Mariner Valley is the largest canyon among the planets. Its length is 4500 km and the depth is 11 m.

Jupiter

It is the largest planet in the solar system. Jupiter is 318 times heavier than Earth and 2.5 times more massive than other planets. The main constituents of the planet are helium and hydrogen. Jupiter radiates a lot of heat - 4 * 1017 W. To become a star like the Sun, it must reach a mass 70 times greater than the current one. The planet has the largest number of satellites - 63. Europa, Callisto, Ganymede and Io are the largest of them. Ganymede is also the largest moon in the entire solar system and is even larger than Mercury. Jupiter's atmosphere is full of vortices that have a brown-red color band of clouds, or a giant storm known as the Great Red Spot since the 17th century.

Saturn

Like Jupiter, it is a large planet that follows Jupiter in size. A system of rings, which consists of ice particles of various sizes, rocks and dust, distinguishes this planet from others. It has one fewer satellites than Jupiter. The largest are Enceladus and Titan. In composition, Saturn resembles Jupiter, but in density it is inferior to the simplest water. The atmosphere looks quite uniform and calm, which can be explained by a dense layer of fog. Saturn has a huge wind speed, it can reach 1800 km per hour.

Uranus

This planet was the first to be discovered using a telescope. Uranus is the only planet in the solar system that lies on its side and revolves around the sun. Uranus has 27 satellites, which are named after the heroes of Shakespeare's plays. The largest among them are Titania, Oberon and Umbriel. Uranus contains a large number of high-temperature modifications of ice. It is also the coldest planet. The temperature here is minus 224 degrees Celsius.

Neptune

It is the most distant planet from the Sun, although until 2006 this title belonged to Pluto. This planet was discovered without the help of a telescope, but by mathematical calculations. The existence of Neptune was suggested to scientists by Uranus, on which strange changes were discovered while moving in its own orbit. The planet has 13 satellites. The largest among them is Triton. Its peculiarity is that it moves opposite to the planet. The strongest winds in the solar system blow in the same direction, reaching speeds of up to 2200 km per hour. The compositions of Neptune and Uranus are similar, but it is also similar in composition to Jupiter and Saturn. The planet has an internal heat source, from which it receives 2.5 times more energy than from the Sun. The outer layers of the atmosphere contain methane, which gives the planet a blue tint.

That's how mysterious the world of space is. Many satellites and planets have their own characteristics. Scientists are making changes to this world, for example, excluding Pluto from the list of planets.

Explore the planets on the portal site - it's very interesting.

The rotation of the planets

All planets, in addition to their orbit, also rotate around their axis. The period for which they make a complete revolution is defined as the epoch. Large quantity planets in the solar system rotate in the same direction around the axis as around the sun, but Uranus and Venus rotate in the opposite direction. Scientists observe a large difference in the length of the day on the planets - Venus takes 243 Earth days to complete one rotation around its axis, while the planets of the gas giant group need only a couple of hours. The rotation period of exoplanets is not known, but their close location to the stars means that eternal day reigns on one side, and eternal night reigns on the other.

Why are all planets so different? Due to the high temperature closer to the star, the ice and gas evaporated very quickly. The giant planets could not form, but there was an accumulation of metal particles. Thus, Mercury was formed, which contains the largest amount of metals. The farther we are from the center, the lower the temperature. Celestial bodies appeared, where a significant percentage was made up of rocks. The four planets that are closer to the center of the solar system are called the inner planets. With the discovery of new systems, more and more questions arise. New research will help answer them.

Scientists claim that our system is unique. All planets are built in a strict order. The largest is closer to the Sun, respectively, the smallest is farther. Our system has a more complex structure, because the planets are not lined up by their mass. The sun makes up more than 99 percent of all objects in the system.

The solar system is a planetary system that includes the central star - the Sun - and all the natural objects of space revolving around it. It was formed by gravitational compression of a gas and dust cloud about 4.57 billion years ago. We will find out which planets are part of the solar system, how they are located in relation to the Sun and their brief description.

Brief information about the planets of the solar system

The number of planets in the solar system is 8, and they are classified in order of distance from the Sun:

• Inner planets or terrestrial planets- Mercury, Venus, Earth and Mars. They consist mainly of silicates and metals.
• outer planets- Jupiter, Saturn, Uranus and Neptune are the so-called gas giants. They are much more massive than the terrestrial planets. The largest planets in the solar system, Jupiter and Saturn, are composed mainly of hydrogen and helium; smaller gas giants, Uranus and Neptune, in addition to hydrogen and helium, contain methane and carbon monoxide in their atmospheres.

Rice. 1. Planets of the solar system.

The list of planets in the solar system in order from the sun is as follows: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. By listing the planets from largest to smallest, this order changes. The largest planet is Jupiter, followed by Saturn, Uranus, Neptune, Earth, Venus, Mars and finally Mercury.

All planets revolve around the Sun in the same direction as the Sun's rotation (counterclockwise as viewed from the north pole of the Sun).

Mercury has the highest angular velocity - it manages to make a complete revolution around the Sun in just 88 Earth days. And for the most distant planet - Neptune - the period of revolution is 165 Earth years.

Most of the planets rotate around their axis in the same direction as they revolve around the Sun. The exceptions are Venus and Uranus, and Uranus rotates almost "lying on its side" (axis tilt is about 90 degrees).

TOP 2 articleswho read along with this

Table. The sequence of the planets in the solar system and their features.

Planet	Distance from the Sun	Period of circulation	Rotation period	Diameter, km.	Number of satellites	Density g / cu. cm.
Mercury

Terrestrial planets (inner planets)

The four planets closest to the Sun consist mainly of heavy elements, have a small number of satellites, and have no rings. They are largely composed of refractory minerals such as silicates that form their mantle and crust, and metals such as iron and nickel that form their core. Three of these planets - Venus, Earth and Mars - have an atmosphere.

• Mercury- is the closest planet to the Sun and the smallest planet in the system. The planet has no satellites.
• Venus- is close in size to the Earth and, like the Earth, has a thick silicate shell around the iron core and atmosphere (because of this, Venus is often called the "sister" of the Earth). However, the amount of water on Venus is much less than on Earth, and its atmosphere is 90 times denser. Venus has no satellites.

Venus is the hottest planet in our system, with surface temperatures exceeding 400 degrees Celsius. Most probable cause such a high temperature is the greenhouse effect that occurs due to the dense atmosphere rich in carbon dioxide.

Rice. 2. Venus is the hottest planet in the solar system

• Earth- is the largest and densest of the terrestrial planets. The question of whether life exists anywhere other than Earth remains open. Among the terrestrial planets, the Earth is unique (primarily due to the hydrosphere). Earth's atmosphere is radically different from the atmospheres of other planets - it contains free oxygen. The Earth has one natural satellite - the Moon, the only large satellite of the planets of the terrestrial group of the solar system.
• Mars smaller than Earth and Venus. It has an atmosphere composed mainly of carbon dioxide. On its surface there are volcanoes, the largest of which, Olympus, exceeds the size of all terrestrial volcanoes, reaching a height of 21.2 km.

Outer region of the solar system

The outer region of the solar system is the location of the gas giants and their satellites.

• Jupiter- has a mass of 318 times more than the earth, and 2.5 times more massive than all the other planets combined. It consists mainly of hydrogen and helium. Jupiter has 67 moons.
• Saturn- known for its extensive ring system, it is the least dense planet in the solar system (its average density is less than that of water). Saturn has 62 moons.

Rice. 3. Planet Saturn.

• Uranus- the seventh planet from the Sun is the lightest of the giant planets. What makes it unique among other planets is that it rotates "lying on its side": the inclination of its axis of rotation to the plane of the ecliptic is approximately 98 degrees. Uranus has 27 moons.
• Neptune is the last planet in the solar system. Although slightly smaller than Uranus, it is more massive and therefore denser. Neptune has 14 known moons.

What have we learned?

One of the interesting topics of astronomy is the structure of the solar system. We learned what names of the planets of the solar system are, in what order they are located in relation to the Sun, what are their distinctive features and brief characteristics. This information so interesting and informative that it will be useful even for children in grade 4.

Topic quiz

Report Evaluation

Average rating: 4.5. Total ratings received: 609.