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 new star The sun and our entire solar system.
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:
Planets terrestrial group: And . These planets are small in size with a rocky surface and are closest to the Sun.
Giant planets: And . This major planets, consisting mainly of gas and characterized by the presence of rings consisting of icy dust and many rocky pieces.
But does not fall into any group because, despite its location in the solar system, it is located too far from the Sun and has a very small diameter, only 2320 km, which is half the diameter of Mercury.
Planets of the Solar System
Let's begin a fascinating acquaintance with the planets of the Solar System in order of their location from the Sun, and also consider their main satellites and some other space objects (comets, asteroids, meteorites) in the gigantic expanses of our planetary system.
Rings and moons of Jupiter: Europa, Io, Ganymede, Callisto and others...
The planet Jupiter is surrounded by a whole family of 16 satellites, and each of them has its own unique features...
Rings and moons of Saturn: Titan, Enceladus and others...
Not only the planet Saturn has characteristic rings, but also other giant planets. The rings around Saturn are particularly visible because they are made up of billions of fine particles, which 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. Interesting fact that the Triton satellite has the opposite 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 state into steam) many kilometers into the atmosphere. During its mission, Voyager 2 discovered six more moons of the planet Neptune...
The new words couldn’t fit into my head. It also happened that a natural history textbook set us the goal of remembering the location of the planets of the solar system, and we were already selecting means to justify it. Among the many options for solving this problem, there are several interesting and practical ones.
Mnemonics in its purest form
The ancient Greeks came up with a solution for modern students. It is not for nothing that the term “mnemonics” comes from a consonant Greek word, literally meaning “the art of remembering.” This art gave rise to a whole system of actions aimed at memorizing a large amount of information - “mnemonics”.
They are very convenient to use if you simply need to store in memory a whole list of any names, a list important addresses or phones or remember the sequence of objects. In the case of the planets of our system, this technique is simply irreplaceable.
We play association or “Ivan gave birth to a girl...”
Each of us remembers and knows this poem from elementary school. This is a mnemonic counting rhyme. We are talking about that couplet, thanks to which it becomes easier for a child to remember the cases of the Russian language - “Ivan Gave Birth to a Girl - Ordered to Drag the Diaper” (respectively - Nominative, Genitive, Dative, Accusative, Instrumental and Prepositional).
Is it possible to do the same with the planets of the solar system? - Undoubtedly. Quite a large number of mnemonics have already been invented for this astronomical educational program. The main thing you need to know is that they are all based on associative thinking. For some it is easier to imagine an object similar in shape to the one being remembered, for others it is enough to imagine a chain of names in the form of a kind of “cipher”. Here are just a few tips on how best to record their location in memory, taking into account their distance from the central star.
Funny pictures
The order of removal of our planets star system from the Sun can be remembered through visual images. To begin, associate with each planet an image of an object or even a person. Then imagine these pictures one by one, in the sequence in which the planets are located inside the Solar System.
- Mercury. If you have never seen images of this ancient Greek god, try to remember the late lead singer of the group “Queen” - Freddie Mercury, whose surname is similar to the name of the planet. It is unlikely, of course, that children can know who this uncle is. Then we suggest you come up with simple phrases, where the first word would begin with the syllable MER, and the second with KUR. And they must necessarily describe specific items, which will then become a “picture” for Mercury (this method can be used as the most extreme option with each of the planets).
- Venus. Many people have seen the statue of Venus de Milo. If you show her to children, they will easily be able to remember this “armless aunt.” Plus, educate the younger generation. You can ask them to remember some acquaintance, classmate or relative with that name - in case there are such people in their social circle.
- Earth. Everything is simple here. Everyone must imagine themselves, an inhabitant of the Earth, whose “picture” stands between two planets located in space before and after ours.
- Mars. In this case, advertising can become not only an “engine of trade”, but also scientific knowledge. We think you understand that you need to imagine the popular imported chocolate bar in place of the planet.
- Jupiter. Try to imagine some landmark of St. Petersburg, for example, the Bronze Horseman. Yes, even if the planet begins in the south, but “ Northern capital» Locals call it Peter. For children, such an association may not be beneficial, so invent a phrase with them.
- Saturn. Such a “handsome man” does not need any visual image, because everyone knows him as a planet with rings. If you still have difficulties, imagine a sports stadium with a running track. Moreover, such an association has already been used by the creators of one animated film on a space theme.
- Uranus. The most effective in this case will be a “picture” in which someone is very happy about some achievement and seems to shout “Hurray!” Agree - every child is capable of adding one letter to this exclamation.
- Neptune. Show your children the cartoon "The Little Mermaid" - let them remember Ariel's dad - the King with a mighty beard, impressive muscles and a huge trident. And it doesn’t matter that in the story His Majesty’s name is Triton. Neptune also had this tool in his arsenal.
Now, once again mentally imagine everything (or everyone) that reminds you of the planets of the solar system. Flip through these images, like pages in a photo album, from the first “picture”, which is closest to the Sun, to the last, whose distance from the star is the greatest.
“Look, what kind of rhymes have turned out...”
Now - to mnemonics, which are based on the “initials” of the planets. Remembering the order of the planets of the solar system is indeed easiest to do by the first letters. This type of “art” is ideal suitable for those, who is not so clearly developed imaginative thinking, but its associative form is fine.
The most striking examples of versification in order to record the order of planets in memory are the following:
“The Bear Comes Out Behind the Raspberry - The Lawyer Managed to Escape the Lowlands”;
“We Know Everything: Yulia’s Mom Stood on Stilts in the Morning.”
You can, of course, not write a poem, but simply choose words for the first letters in the names of each of the planets. A little advice: in order not to confuse the places of Mercury and Mars, which begin with the same letter, put the first syllables at the beginning of your words - ME and MA, respectively.
For example: In some places Golden Cars could be seen, Julia seemed to see Us.
You can come up with such proposals ad infinitum - as much as your imagination allows. In a word, try, practice, remember...
Planets of the solar system - a little history
Previously, a planet was considered to be any body that orbits a star, glows with light reflected from it, and is larger than an asteroid.
Even in Ancient Greece, they mentioned seven luminous bodies that move across the sky against the backdrop of fixed stars. These cosmic bodies were: the Sun, Mercury, Venus, Moon, Mars, Jupiter and Saturn. The earth was not included in this list, since the ancient Greeks considered the earth to be the center of all things.
And only in the 16th century Nicolaus Copernicus in his scientific work entitled “On the Revolution of the Celestial Spheres,” he came to the conclusion that it was not the Earth, but the Sun that should be at the center of the planetary system. Therefore, the Sun and Moon were removed from the list, and the Earth was added to it. And after the advent of telescopes, Uranus and Neptune were added, in 1781 and 1846, respectively.
Last open planet The solar system from 1930 until recently was considered Pluto.
And now, almost 400 years after the creation of the world's first telescope for observing stars by Galileo Galilei, astronomers came to the following definition planets.
Planet- This celestial body, which must satisfy four conditions:
the body must revolve around a star (for example, around the Sun);
the body must have sufficient gravity to have a spherical or close to it shape;
the body should not have other large bodies near its orbit;
the body should not be a star.
In turn polar star is a cosmic body that emits light and is a powerful source of energy. This is explained, firstly, by the events occurring in it thermonuclear reactions, and secondly, the processes gravitational compression, as a result of which the release huge amount energy.
Planets of the Solar System today
solar system is a planetary system that consists of a central star - the Sun - and all natural space objects, revolving around it.
So, today the solar system consists of eight planets: four inner, so-called terrestrial planets, and four outer planets, called gas giants.
The terrestrial planets include Earth, Mercury, Venus and Mars. All of them consist mainly of silicates and metals.
The outer planets are Jupiter, Saturn, Uranus and Neptune. Gas giants are composed mainly of hydrogen and helium.
The sizes of the planets of the Solar System vary both within groups and between groups. Thus, gas giants are much larger and more massive than terrestrial planets.
Mercury is closest to the Sun, then as it moves away: Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
It would be wrong to consider the characteristics of the planets of the Solar System without paying attention to its main component: the Sun itself. Therefore, we will start with it. 
The sun planet is the star that gave rise to all life in the solar system. Planets, dwarf planets and their satellites, asteroids, comets, meteorites and cosmic dust revolve around it.
The Sun arose about 5 billion years ago, is a spherical, hot plasma ball and has a mass that is more than 300 thousand times the mass of the Earth. The surface temperature is more than 5000 degrees Kelvin, and the core temperature is more than 13 million K.
The sun is one of the largest and most bright stars in our galaxy, which is called galaxy Milky Way. The Sun is located at a distance of about 26 thousand light years from the center of the Galaxy and makes full turn around it for about 230-250 million years! For comparison, the Earth makes a full revolution around the Sun in 1 year.
Mercury planet
Mercury is the smallest planet in the system, which is closest to the Sun. Mercury has no satellites.
The surface of the planet is covered with craters that appeared about 3.5 billion years ago as a result of massive bombardment by meteorites. The diameter of the craters can range from a few meters to more than 1000 km.
The atmosphere of Mercury is very thin, consists mainly of helium and is inflated solar wind. Since the planet is located very close to the Sun and does not have an atmosphere that would retain heat at night, the surface temperature ranges from -180 to +440 degrees Celsius.
By earthly standards, Mercury completes a full revolution around the Sun in 88 days. But a Mercury day is equal to 176 Earth days.
Venus planet
Venus is the second planet closest to the Sun in the solar system. Venus is only slightly smaller in size than Earth, which is why it is sometimes called “Earth’s sister.” Has no satellites.
The atmosphere consists of carbon dioxide mixed with nitrogen and oxygen. The air pressure on the planet is more than 90 atmospheres, which is 35 times more than on Earth.
Carbon dioxide and, as a consequence, greenhouse effect, dense atmosphere, as well as proximity to the Sun allow Venus to bear the title of “the most hot planet" The temperature on its surface can reach 460°C.
Venus is one of the brightest objects in the earth's sky after the Sun and Moon.
Planet Earth 
Earth is the only planet known today in the Universe on which there is life. The earth has largest sizes, mass and density among the so-called inner planets Solar system.
The age of the Earth is about 4.5 billion years, and life appeared on the planet about 3.5 billion years ago. Moon - natural satellite, the largest of the satellites of the terrestrial planets.
The Earth's atmosphere is fundamentally different from the atmospheres of other planets due to the presence of life. Most The atmosphere consists of nitrogen, and also includes oxygen, argon, carbon dioxide and water vapor. Ozone layer and the Earth's magnetic field, in turn, weaken the life-threatening influence of solar and cosmic radiation.
Due to the carbon dioxide contained in the atmosphere, the greenhouse effect also occurs on Earth. It is not as pronounced as on Venus, but without it the air temperature would be about 40°C lower. Without an atmosphere, temperature fluctuations would be very significant: according to scientists, from -100°C at night to +160°C during the day.
About 71% of the Earth's surface is occupied by the world's oceans, the remaining 29% are continents and islands.
Mars planet
Mars is the seventh largest planet in the solar system. "Red Planet", as it is also called due to the presence large quantity iron oxide in the soil. Mars has two satellites: Deimos and Phobos.
The atmosphere of Mars is very thin, and the distance to the Sun is almost one and a half times greater than that of the Earth. Therefore, the average annual temperature on the planet is -60°C, and temperature changes in some places reach 40 degrees during the day.
Distinctive features of the surface of Mars are impact craters and volcanoes, valleys and deserts, icy polar ice caps like those on earth. The tallest mountain in the solar system is located on Mars: extinct volcano Olympus, whose height is 27 km! And also the largest canyon: Valles Marineris, whose depth reaches 11 km and length – 4500 km 
Jupiter planet
Jupiter is the most big planet Solar system. It is 318 times heavier than the Earth, and almost 2.5 times more massive than all the planets in our system combined. In its composition, Jupiter resembles the Sun - it consists mainly of helium and hydrogen - and emits a huge amount of heat equal to 4 * 1017 W. However, in order to become a star like the Sun, Jupiter must be 70-80 times heavier.
Jupiter has as many as 63 satellites, of which it makes sense to list only the largest - Callisto, Ganymede, Io and Europa. Ganymede is the largest moon in the solar system, even larger than Mercury.
Due to certain processes in internal atmosphere Jupiter, in its outer atmosphere there are many vortex structures, for example, bands of clouds in brown-red hues, as well as the Great Red Spot, a giant storm known since the 17th century.
Saturn planet
Saturn is the second largest planet in the solar system. Business card Saturn is, of course, its ring system, which consists mainly of icy particles of various sizes (from tenths of a millimeter to several meters), as well as rocks and dust.
Saturn has 62 moons, the largest of which are Titan and Enceladus.
In its composition, Saturn resembles Jupiter, but in density it is inferior even to ordinary water.
The planet's outer atmosphere appears calm and uniform, which is explained by a very dense layer of fog. However, wind speeds in some places can reach 1800 km/h.
Uranus planet
Uranus is the first planet discovered using a telescope, and also the only planet in the solar system, which revolves around the sun, “lying on its side.”
Uranus has 27 moons, which are named after Shakespearean heroes. The largest of them are Oberon, Titania and Umbriel.
The composition of the planet differs from gas giants in the presence of a large number of high-temperature modifications of ice. Therefore, along with Neptune, scientists have classified Uranus as an “ice giant.” And if Venus has the title of “hottest planet” in the solar system, then Uranus is the most cold planet With minimum temperature about -224°C.
Neptune planet
Neptune is the most distant planet in the solar system from the center. The story of its discovery is interesting: before observing the planet through a telescope, scientists used mathematical calculations to calculate its position in the sky. This happened after the discovery of inexplicable changes in the movement of Uranus in its own orbit.
Today, 13 satellites of Neptune are known to science. The largest of them, Triton, is the only satellite that moves in the direction opposite to the rotation of the planet. The most winds also blow against the rotation of the planet. fast winds in the solar system: their speed reaches 2200 km/h.
Neptune's composition is very similar to Uranus, therefore it is the second “ice giant”. However, like Jupiter and Saturn, Neptune has internal source heat and emits 2.5 times more energy than it receives from the Sun.
The blue color of the planet is given by traces of methane in the outer layers of the atmosphere.
Conclusion
Pluto, unfortunately, did not manage to get into our parade of planets in the solar system. But there is absolutely no need to worry about this, because all the planets remain in their places, despite changes in scientific views and concepts.
So, we answered the question how many planets are there in the solar system. There are only 8 .
Theories on how it arose , a great many. The first of these was the famous theory put forward by the German philosopher Immanuel Kant in 1755. He believed that the emergence solar system originated from some primary matter, before which it was freely dispersed in space.
One of the subsequent cosmogonic theories is the theory of “catastrophes”. According to it, our planet Earth was formed after some kind of external intervention, for example, a meeting of the Sun with some other star, this meeting could cause the eruption of a certain part of the solar substance. Due to incandescence, gaseous matter quickly cooled and became denser, while forming many small solid particles, their accumulations were a kind of embryos of planets.
Planets of the solar system
The central body in our system is the Sun. It belongs to the class of yellow dwarf stars. The sun represents the most massive object our system of planets. The closest star to Earth, as well as the main body in our planetary system. In our system, the planets are more or less ordinary. There are none, for example, that almost do not reflect light. Images of planets are often used in interior signs.
The very first planet from the Sun in our solar system is Mercury - it is also the smallest planet in the terrestrial group (in addition to Earth and Mercury, it includes Mars and Venus).
Next, second in line, comes Venus. Next comes the Earth - the shelter of all humanity. Our planet has a satellite - the Moon, which is almost 80 times lighter than the Earth. The moon is only companion Earth revolving around the Earth in orbit. After the Sun this is the most bright object in the sky. The fourth planet is Mars - this desert planet has two satellites. Next comes a large group of planets - the so-called giant planets.
The sun and other planets played a big role in different. There were many religions that worshiped the Sun. And astrology, which studies the effect of planets on humans, still influences many people. Astrology used to be considered a science, but nowadays many people consider it a science.
The largest and most massive of all the giants is Jupiter, which represents our solar system in miniature. Jupiter has more than 40 satellites, the largest of which are Ganymede, Io, Europa, and Callisto. These satellites have another name - Galilean, in honor of the man who discovered them - Galileo Galilei.
Next comes the giant planet Uranus - it is unusual in that it has a “lying on its side” position - which is why there is enough abrupt change seasons. It has 21 satellites and a distinctive feature in the form of rotation in the opposite direction.
The last giant planet is Neptune (Neptune’s largest satellite is Triton). All giant planets have distinctive feature in the form of many satellites, as well as a system of rings.
But the farthest and last planet in the solar system is Pluto, which is also the smallest planet in our system. Pluto has one satellite, Charon, which is slightly smaller than the planet itself.
