Inner planets terrestrial planets closest to the Sun 4 large planets - Mercury, Venus, Earth, Mars - having a number of similar physical characteristics. See Planets.
Big Soviet encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .
See what “Inner planets” are in other dictionaries:
solar system Mercury, Venus, Earth and Mars. They are also called terrestrial planets, in contrast to the outer planets of the giant planets. According to a number of cosmogonic theories, in a significant part of extrasolar planetary systems, exoplanets are also... ... Wikipedia
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- (late Lat., singular planeta, from Greek. astèr planétes wandering star) large celestial bodies moving around the Sun and glowing with reflected sunlight; The size and mass of the planet are several orders of magnitude smaller than that of the Sun.... ... Great Soviet Encyclopedia
Comparative sizes of the terrestrial planets The terrestrial planets are four planets ... Wikipedia
Gas giants compared to the Sun Gas planets (giant planets, gas giants) are planets that have a significant proportion of gas in their composition (mainly hydrogen and helium). In the Solar System it is Jup... Wikipedia
Inner and outer planets. Configurations of the planets Movements of the Sun and planets celestial sphere display only their visible, that is, movements that appear to an earthly observer. Moreover, any movements of luminaries across the celestial sphere are not related to... ... Wikipedia
The sun and the celestial bodies orbiting around it are 9 planets, more than 63 satellites, four ring systems of the giant planets, tens of thousands of asteroids, a myriad of meteoroids ranging in size from boulders to dust grains, as well as millions of comets. IN… … Collier's Encyclopedia
Image of the Solar System from Andreas Cellarius' book Harmonia Macrocosmica (1708) Heliocentric system world the idea that the Sun is the central celestial body around which the Earth and others revolve ... Wikipedia
Main article: Cosmogony Cosmogony hypotheses aim to explain the uniformity of the movement and composition of celestial bodies. They proceed from the concept of the initial state of matter, filling all space, which has certain properties... ... Wikipedia
Books
- Persepolis Rising, Corey James. "The Rise of Persepolis" is a dizzying, adventurous SF, the seventh book in the "Space" series. An old enemy returns. In a thousand star systems covered by the expansion of humanity, they are looking for...
- Earth --- a restless planet: Atmosphere, hydrosphere, lithosphere: A book for schoolchildren... and not only, Tarasov L.V.. This popular educational book opens to the inquisitive reader the world of the natural spheres of the Earth - the atmosphere, hydrosphere, lithosphere. The book describes in an interesting and intelligible form...
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 in many times more than Earth, but compared to the Sun, they are not large at all:
Computer calculations have shown that the giant planets are playing 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” the word from a sling at 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 so, then nuclear reactions They have to go already, otherwise the energy simply won’t come from anywhere. And this is a sign of a star, not a planet... 
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, having 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 of the moons of Jupiter, is also the largest of the moons of the planets 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.
Next comes an equally famous body of the solar system - the giant planet Saturn, which is known primarily 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, whose size is more 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 companion 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! 
The Cassini research station has been orbiting 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, the density of Saturn is approximately 9.1 times less than the density of the 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 is an 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, he turns to the Sun, now Southern, then 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... The reason for this is, again, low density 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 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. 
Neptune, 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 Galii observed Neptune long before this, back in 1612, with his first telescope! But... he did not recognize it as a planet, 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 force is only 1.14 g, that is, almost the same as on Earth, like the two previous giant planets.
or tell your friends:Planets of the Solar System
According to the official position of the International Astronomical Union (IAU), the organization that assigns names to astronomical objects, there are only 8 planets.
Pluto was removed from the planet category in 2006. because There are objects in the Kuiper Belt that are larger/equal in size to Pluto. Therefore, even if it is taken as a full-fledged heavenly body, then it is necessary to add Eris to this category, which has almost the same size as Pluto.
By MAC definition, there are 8 known planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
All planets are divided into two categories depending on their physical characteristics: terrestrial planets and gas giants.
Schematic representation of the location of the planets
Terrestrial planets
Mercury
The smallest planet in the solar system has a radius of only 2440 km. The period of revolution around the Sun, equated to an earthly year for ease of understanding, is 88 days, while Mercury manages to rotate around its own axis only one and a half times. Thus, his day lasts approximately 59 Earth days. For a long time it was believed that this planet was always turned to the Sun with the same side, since the periods of its visibility from the Earth were repeated with a frequency approximately equal to four Mercury days. This misconception was dispelled with the advent of the ability to use radar research and conduct continuous observations using space stations. The orbit of Mercury is one of the most unstable; not only the speed of movement and its distance from the Sun change, but also the position itself. Anyone interested can observe this effect.
Mercury in color, image from the MESSENGER spacecraft
Its proximity to the Sun is the reason why Mercury is subject to the largest temperature changes among the planets in our system. The average daytime temperature is about 350 degrees Celsius, and the nighttime temperature is -170 °C. Sodium, oxygen, helium, potassium, hydrogen and argon were detected in the atmosphere. There is a theory that it was previously a satellite of Venus, but so far this remains unproven. It does not have its own satellites.
Venus
The second planet from the Sun, the atmosphere is almost entirely composed of carbon dioxide. It is often called the Morning Star and the Evening Star, because it is the first of the stars to become visible after sunset, just as before dawn it continues to be visible even when all the other stars have disappeared from view. The percentage of carbon dioxide in the atmosphere is 96%, there is relatively little nitrogen in it - almost 4%, and water vapor and oxygen are present in very small quantities.
Venus in the UV spectrum
Such an atmosphere creates a greenhouse effect; the temperature on the surface is even higher than that of Mercury and reaches 475 °C. Considered the slowest, a Venusian day lasts 243 Earth days, which is almost equal to a year on Venus - 225 Earth days. Many call it Earth's sister because of its mass and radius, the values of which are very close to those of Earth. The radius of Venus is 6052 km (0.85% of Earth's). Like Mercury, there are no satellites.
The third planet from the Sun and the only one in our system where there is liquid water, without which life on the planet could not have developed. At least life as we know it. The radius of the Earth is 6371 km and, unlike other celestial bodies in our system, more than 70% of its surface is covered with water. The rest of the space is occupied by continents. Another feature of the Earth is the tectonic plates hidden under the planet's mantle. At the same time, they are able to move, albeit at a very low speed, which over time causes changes in the landscape. The speed of the planet moving along it is 29-30 km/sec.
Our planet from space
One revolution around its axis takes almost 24 hours, and a complete passage through the orbit lasts 365 days, which is much longer in comparison with its closest neighboring planets. The Earth's day and year are also accepted as a standard, but this is done only for the convenience of perceiving time periods on other planets. The Earth has one natural satellite - the Moon.
Mars
The fourth planet from the Sun, known for its thin atmosphere. Since 1960, Mars has been actively explored by scientists from several countries, including the USSR and the USA. Not all exploration programs have been successful, but water found at some sites suggests that primitive life exists on Mars, or existed in the past.
The brightness of this planet allows it to be seen from Earth without any instruments. Moreover, once every 15-17 years, during the Confrontation, it becomes the brightest object in the sky, eclipsing even Jupiter and Venus.
The radius is almost half that of Earth and is 3390 km, but the year is much longer - 687 days. He has 2 satellites - Phobos and Deimos .
Visual model of the solar system
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Sun
The Sun is a star that is a hot ball of hot gases at the center of our Solar System. Its influence extends far beyond the orbits of Neptune and Pluto. Without the Sun and its intense energy and heat, there would be no life on Earth. There are billions of stars like our Sun scattered throughout the Milky Way galaxy.
Mercury
Sun-scorched Mercury is only slightly larger than Earth's satellite the Moon. Like the Moon, Mercury is practically devoid of an atmosphere and cannot smooth out the traces of impact from falling meteorites, so it, like the Moon, is covered with craters. The day side of Mercury gets very hot from the Sun, while on the night side the temperature drops hundreds of degrees below zero. There is ice in the craters of Mercury, which are located at the poles. Mercury completes one revolution around the Sun every 88 days.
Venus
Venus is a world of monstrous heat (even more than on Mercury) and volcanic activity. Similar in structure and size to Earth, Venus is covered in a thick and toxic atmosphere that creates a strong Greenhouse effect. This scorched world is hot enough to melt lead. Radar images through the powerful atmosphere revealed volcanoes and deformed mountains. Venus rotates in the opposite direction from the rotation of most planets.
Earth is an ocean planet. Our home, with its abundance of water and life, makes it unique in our solar system. Other planets, including several moons, also have ice deposits, atmospheres, seasons and even weather, but only on Earth did all these components come together in a way that made life possible.
Mars
Although details of the surface of Mars are difficult to see from Earth, telescope observations show that Mars has seasons and white spots at the poles. For decades, people believed that the bright and dark areas on Mars were patches of vegetation, that Mars might be a suitable place for life, and that water existed in the polar ice caps. When spacecraft Mariner 4 arrived at Mars in 1965, and many scientists were shocked to see photographs of the gloomy, cratered planet. Mars turned out to be a dead planet. More recent missions, however, have revealed that Mars holds many mysteries that remain to be solved.
Jupiter
Jupiter is the most massive planet in our solar system, has four large satellites and many small moons. Jupiter forms a kind of miniature solar system. To become a full-fledged star, Jupiter needed to become 80 times more massive.
Saturn
Saturn is the farthest of the five planets known before the invention of the telescope. Like Jupiter, Saturn is composed primarily of hydrogen and helium. Its volume is 755 times greater than that of the Earth. Winds in its atmosphere reach speeds of 500 meters per second. These fast winds, combined with heat rising from the planet's interior, cause the yellow and golden streaks we see in the atmosphere.
Uranus
The first planet found using a telescope, Uranus was discovered in 1781 by astronomer William Herschel. The seventh planet is so far from the Sun that one revolution around the Sun takes 84 years.
Neptune
Distant Neptune rotates almost 4.5 billion kilometers from the Sun. It takes him 165 years to complete one revolution around the Sun. It is invisible to the naked eye due to its vast distance from Earth. Interestingly, its unusual elliptical orbit intersects with the orbit of the dwarf planet Pluto, which is why Pluto is inside the orbit of Neptune for about 20 years out of 248 during which it makes one revolution around the Sun.
Pluto
Tiny, cold and incredibly distant, Pluto was discovered in 1930 and was long considered the ninth planet. But after discoveries of Pluto-like worlds that were even further away, Pluto was reclassified as a dwarf planet in 2006.
Planets are giants
There are four gas giants located beyond the orbit of Mars: Jupiter, Saturn, Uranus, Neptune. They are located in the outer solar system. They are distinguished by their massiveness and gas composition.
Planets of the solar system, not to scale
Jupiter
Fifth in a row from the Sun and largest planet our system. Its radius is 69912 km, it is 19 times larger than the Earth and only 10 times smaller than the Sun. The year on Jupiter is not the longest in the solar system, lasting 4333 Earth days (less than 12 years). His own day has a duration of about 10 Earth hours. The exact composition of the planet’s surface has not yet been determined, but it is known that krypton, argon and xenon are present on Jupiter in much greater quantities. large quantities than on the Sun.
There is an opinion that one of the four gas giants is actually a failed star. This theory is supported by the most a large number of Jupiter has many satellites - as many as 67. To imagine their behavior in the planet’s orbit, you need a fairly accurate and clear model of the solar system. The largest of them are Callisto, Ganymede, Io and Europa. Moreover, Ganymede is the largest satellite of the planets in the entire solar system, its radius is 2634 km, which is 8% greater than the size of Mercury, the smallest planet in our system. Io has the distinction of being one of only three moons with an atmosphere.
Saturn
The second largest planet and the sixth in the solar system. Compared to other planets, its composition is most similar to the Sun chemical elements. The radius of the surface is 57,350 km, the year is 10,759 days (almost 30 Earth years). A day here lasts a little longer than on Jupiter - 10.5 Earth hours. In terms of the number of satellites, it is not much behind its neighbor - 62 versus 67. The largest satellite of Saturn is Titan, just like Io, which is distinguished by the presence of an atmosphere. Slightly smaller in size, but no less famous are Enceladus, Rhea, Dione, Tethys, Iapetus and Mimas. It is these satellites that are the objects for the most frequent observation, and therefore we can say that they are the most studied in comparison with the others.
For a long time, the rings on Saturn were considered a unique phenomenon unique to it. Only recently it was established that all gas giants have rings, but in others they are not so clearly visible. Their origin has not yet been established, although there are several hypotheses about how they appeared. In addition, it was recently discovered that Rhea, one of the satellites of the sixth planet, also has some kind of rings.
The planets of the Solar System are divided into internal (in which the orbits are located inside the Earth's orbit) and external (orbits larger than the Earth's orbit). For various studies Both (inner planets) and , (outer planets) are easily accessible.
Keeping an eye on the inner planet from Earth, you will notice the following points: a conjunction where the planet is located behind the Sun and is not visible. After a certain time, the planet on the left emerges from behind the Sun and becomes available for contemplation in the rays of the evening dawn in the west.
Little by little, the planet is able to reach the greatest distance from the Sun, at which the conditions of evening visibility are most favorable, and then begins to approach the Sun and again connects with the Sun, appearing before it. If the plane of its orbit coincided with the flat orbit of the Earth, then at the moment the planet would be projected on the disk of the Sun and could become visible as a black spot. Usually the planet is located below or above the Sun and does not enter into conjunction.
After conjunctions, the planet falls with right side from the Sun, reaches western elongation, passes through a close crescent to disk phase, and is visible in the morning in the east. Then the movement changes to reverse side, from right to left, when the planet moves towards the Sun, decreasing in angle size, and approaching full phase.
Following its exit from behind the Sun, the planet is visible in perfect phase, and in eastern elongation only half of the entire illuminated disk is visible, then the phase decreases, but the angular size of the crescent increases as the planet approaches the Earth.
The inner planet does not move far from the Sun and is always observed in the rays of the evening or morning dawn. The magnitude of Mercury's elongation is not very large - no more than twenty-eight degrees Celsius; the rest of the time Mercury always hides near the Sun, and is visible only next to elongation.
Venus is capable of moving away from the Sun by forty-five to forty-eight degrees and is easily noted as an evening or morning star as the most bright object in the sky. In approximately 1.5 years, the position of Venus will repeat.
The outer planets are capable of moving away from the Sun at any distance, and are always visible in perfect phase. While the outer planet is visible in the west after sunset, it is able to move among the stars in a straight motion like the Sun.
solar system– these are 8 planets and more than 63 of their satellites, which are being discovered more and more often, several dozen comets and a large number of asteroids. All cosmic bodies move along their own clearly directed trajectories around the Sun, which is 1000 times heavier than all the bodies in the solar system combined. The center of the solar system is the Sun, a star around which the planets orbit. They do not emit heat and do not glow, but only reflect the light of the Sun. There are now 8 officially recognized planets in the solar system. Let us briefly list them all in order of distance from the sun. And now a few definitions.
Planet is a celestial body that must satisfy four conditions:
1. the body must revolve around a star (for example, around the Sun);
2. the body must have sufficient gravity to have a spherical or close to it shape;
3. the body should not have other large bodies near its orbit;
4. the body should not be a star
Satellites of the planets. The solar system also includes the Moon and natural satellites other planets that they all have, except Mercury and Venus. Over 60 satellites are known. Most of the satellites of the outer planets were discovered when they received photographs taken by robotic spacecraft. Jupiter's smallest satellite, Leda, is only 10 km across.
is a star without which life on Earth could not exist. It gives us energy and warmth. According to the classification of stars, the Sun is a yellow dwarf. Age about 5 billion years. It has a diameter at the equator of 1,392,000 km, 109 times larger than that of Earth. The rotation period at the equator is 25.4 days and 34 days at the poles. The mass of the Sun is 2x10 to the 27th power of tons, approximately 332,950 times the mass of the Earth. The temperature inside the core is approximately 15 million degrees Celsius. The surface temperature is about 5500 degrees Celsius. By chemical composition The sun is made up of 75% hydrogen, and the other 25% elements are mostly helium. Now let’s figure out in order how many planets revolve around the sun, in the solar system and the characteristics of the planets.
The four inner planets (closest to the Sun) - Mercury, Venus, Earth and Mars - have a solid surface. They are smaller than the four giant planets. Mercury moves faster than other planets, being burned by the sun's rays during the day and freezing at night.
Period of revolution around the Sun: 87.97 days. Diameter at the equator: 4878 km.
Rotation period (rotation around an axis): 58 days.
Surface temperature: 350 during the day and -170 at night.
Atmosphere: very rarefied, helium.
How many satellites: 0.
The main satellites of the planet: 0.
More similar to Earth in size and brightness. Observing it is difficult due to the clouds enveloping it. The surface is a hot rocky desert. 
Period of revolution around the Sun: 224.7 days.
Diameter at the equator: 12104 km.
Rotation period (rotation around an axis): 243 days.
Surface temperature: 480 degrees (average).
Atmosphere: dense, mostly carbon dioxide.
How many satellites: 0.
The main satellites of the planet: 0.
Apparently, the Earth was formed from a gas and dust cloud, like other planets. Particles of gas and dust collided and gradually “grew” the planet. The temperature on the surface reached 5000 degrees Celsius. Then the Earth cooled and became covered with a hard rock crust. But the temperature in the depths is still quite high - 4500 degrees. Rocks in the depths are molten and during volcanic eruptions they flow to the surface. Only on earth there is water. That's why life exists here. It is located relatively close to the Sun in order to receive the necessary heat and light, but far enough so as not to burn out.
Period of revolution around the Sun: 365.3 days. Diameter at the equator: 12756 km.
Period of rotation of the planet (rotation around its axis): 23 hours 56 minutes.
Surface temperature: 22 degrees (average).
Atmosphere: Mainly nitrogen and oxygen.
Number of satellites: 1.
The main satellites of the planet: the Moon.
Because of its resemblance to Earth, it was believed that life existed here. But the spacecraft that descended to the surface of Mars found no signs of life. This is the fourth planet in order. 
Period of revolution around the Sun: 687 days.
Diameter of the planet at the equator: 6794 km.
Rotation period (rotation around an axis): 24 hours 37 minutes.
Surface temperature: –23 degrees (average).
The planet's atmosphere: thin, mostly carbon dioxide.
How many satellites: 2.
The main satellites in order: Phobos, Deimos.
Jupiter, Saturn, Uranus and Neptune are made of hydrogen and other gases. Jupiter exceeds Earth by more than 10 times in diameter, 300 times in mass and 1300 times in volume. It is more than twice as massive as all the planets in the solar system combined. How long does it take for planet Jupiter to become a star? We need to increase its mass by 75 times!
Period of revolution around the Sun: 11 years 314 days. Diameter of the planet at the equator: 143884 km.
Rotation period (rotation around an axis): 9 hours 55 minutes.
Planet surface temperature: –150 degrees (average).
Number of satellites: 16 (+ rings).
The main satellites of the planets in order: Io, Europa, Ganymede, Callisto.
It is number 2, the largest of the planets in the solar system. Saturn attracts attention thanks to its ring system formed of ice, rocks and dust that orbit the planet. There are three main rings with an outer diameter of 270,000 km, but their thickness is about 30 meters. 
Period of revolution around the Sun: 29 years 168 days.
Diameter of the planet at the equator: 120536 km.
Rotation period (rotation around an axis): 10 hours 14 minutes.
Surface temperature: –180 degrees (average).
Atmosphere: Mainly hydrogen and helium.
Number of satellites: 18 (+ rings).
Main satellites: Titan.
A unique planet in the solar system. Its peculiarity is that it rotates around the Sun not like everyone else, but “lying on its side.” Uranus also has rings, although they are harder to see. In 1986, Voyager 2 flew at a distance of 64,000 km, he had six hours to take photographs, which he successfully implemented.
Orbital period: 84 years 4 days. Diameter at the equator: 51118 km.
Period of rotation of the planet (rotation around its axis): 17 hours 14 minutes.
Surface temperature: -214 degrees (average).
Atmosphere: Mainly hydrogen and helium.
How many satellites: 15 (+ rings).
Main satellites: Titania, Oberon.
At the moment, Neptune is considered the last planet in the solar system. Its discovery took place through mathematical calculations, and then it was seen through a telescope. In 1989, Voyager 2 flew past. He took stunning photographs of the blue surface of Neptune and its largest moon, Triton. 
Period of revolution around the Sun: 164 years 292 days.
Diameter at the equator: 50538 km.
Rotation period (rotation around an axis): 16 hours 7 minutes.
Surface temperature: –220 degrees (average).
Atmosphere: Mainly hydrogen and helium.
Number of satellites: 8.
Main satellites: Triton.
On August 24, 2006, Pluto lost its planetary status. The International Astronomical Union has decided which celestial body should be considered a planet. Pluto does not meet the requirements of the new formulation and loses its “planetary status”, at the same time Pluto takes on a new quality and becomes the prototype of a separate class of dwarf planets.
How did the planets appear? Approximately 5–6 billion years ago, one of the gas and dust clouds of our big galaxy (milky way), having the shape of a disk, began to shrink towards the center, little by little forming the present Sun. Further, according to one theory, under the influence of powerful forces of attraction, a large number of dust and gas particles revolving around the Sun began to stick together into balls - forming future planets. As another theory says, the gas and dust cloud immediately broke up into separate clusters of particles, which compressed and became denser, forming the current planets. Now 8 planets revolve around the Sun constantly.
