Planets of the solar system in order. What is the solar system? All planets in order. Giant planets - the largest planets in the solar system

The solar system is a system of planets that includes its center, the Sun, as well as other objects in space. They revolve around the Sun. Until recently, “planet” was the name given to 9 objects in space that revolve around the Sun. Scientists have now established that beyond the boundaries of the solar system there are planets that orbit stars.

In 2006, the Union of Astronomers proclaimed that the planets of the solar system are spherical space objects revolving around the Sun. On the scale of the solar system, the Earth appears extremely small. In addition to the Earth, eight planets revolve around the Sun in their individual orbits. All of them are larger than the Earth in size. Rotate in the plane of the ecliptic.

Planets in the Solar System: types

Location of the terrestrial group in relation to the Sun

The first planet is Mercury, followed by Venus; Next comes our Earth and, finally, Mars.
Terrestrial planets do not have many satellites or moons. Of these four planets, only Earth and Mars have satellites.

Planets that belong to the terrestrial group are highly dense and consist of metal or stone. Basically, they are small and rotate around their axis. Their rotation speed is also low.

Gas giants

These are the four space objects that are at the greatest distance from the Sun: Jupiter is at No. 5, followed by Saturn, then Uranus and Neptune.

Jupiter and Saturn are impressively sized planets made of hydrogen and helium compounds. The density of gas planets is low. They rotate at high speeds, have satellites and are surrounded by rings of asteroids.
The “ice giants,” which include Uranus and Neptune, are smaller; their atmospheres contain methane and carbon monoxide.

Gas giants have a strong gravitational field, so they can attract many cosmic objects, unlike the terrestrial group.

According to scientists, asteroid rings are the remains of moons changed by the gravitational field of the planets.

Dwarf planet

Dwarfs are space objects whose size does not reach the size of a planet, but exceeds the dimensions of an asteroid. There are a great many such objects in the Solar System. They are concentrated in the Kuiper belt region. The satellites of the gas giants are dwarf planets that have left their orbit.

Planets of the Solar System: the process of emergence

According to the cosmic nebula hypothesis, stars are born in clouds of dust and gas, in nebulae.
Due to the force of attraction, substances come together. Under the influence of the concentrated force of gravity, the center of the nebula contracts and stars form. Dust and gases transform into rings. The rings rotate under the influence of gravity, and planetasimals are formed in the whirlpools, which increase in size and attract cosmetic objects to themselves.

Under the influence of gravity, planetesimals are compressed and acquire spherical shapes. The spheres can unite and gradually turn into protoplanets.



There are eight planets within the solar system. They revolve around the Sun. Their location is as follows:
The closest “neighbor” of the Sun is Mercury, followed by Venus, followed by the Earth, then Mars and Jupiter, further from the Sun are Saturn, Uranus and the last one, Neptune.

The solar system - our home - consists of 8 planets and many other cosmic bodies that revolve around a star. Large, medium, small in size, solid and consisting of gases, closest and farthest from the Sun, they live within the system according to a clearly established order.

Until 2006, it was believed that there were 9 planets in the solar system. However, then at the next International Astronomical Congress, the most distant object, Pluto, was crossed off the list. Scientists revised the criteria and left planets that fit the following parameters:

• orbital rotation around a star (Sun);
• gravity and spherical shape;
• the absence of other large cosmic bodies nearby, except for their own satellites.

These planets are in order from the Sun:

1. Mercury. Diameter – 4.9 thousand km.
2. Venus. Diameter – 12.1 thousand km.
3. Earth. Diameter – 12.7 thousand km.
4. Mars. Diameter – 6.8 thousand km.
5. Jupiter. Diameter – 139.8 thousand km.
6. Saturn. Diameter – 116.5 thousand km.
7. Uranus. Diameter – 50.7 thousand km.
8. Neptune. Diameter – 49.2 thousand km.

Attention! Scientists were prompted to revise the parameters by the discovery of another planet-like body - Eris, which turned out to be heavier than Pluto. Both objects were classified as dwarf planets.

Terrestrial planets: Mercury and Venus

The planets in the Solar System are divided into two groups: terrestrial (inner) and gas (outer). They are separated from each other by an asteroid belt. According to one hypothesis, it is a planet that could not form under the strong influence of Jupiter. The terrestrial group includes planets with a solid surface.

There are 8 planets

Mercury– the first object of the system from the sun. Its orbit is the smallest, and it revolves around the star faster than the others. A year here is equal to 88 Earth days. But Mercury rotates very slowly around its axis. The local day here is longer than the local year and amounts to 4224 Earth hours.

Attention! The movement of the sun in the black sky of Mercury is very different from that on Earth. Due to the peculiarities of rotation and orbit at different points, it may look as if the star is freezing, “backing away,” rising and setting several times a day.

Mercury is the smallest planet in the solar system. It is even smaller than some of the satellites of the gas group of planets. Its surface is covered with many craters with a diameter ranging from several meters to hundreds of kilometers. There is almost no atmosphere on Mercury, so the surface can be very hot during the day (+440°C) and cold at night (-180°C). But already at a depth of 1 m the temperature is stable and is approximately +75°C at any time.

Venus- the second planet from the Sun. Its powerful atmosphere of carbon dioxide (more than 96%) hid the surface from human eyes for a long time. Venus is very hot (+460°C), but unlike Mercury, the main reason for this is the greenhouse effect due to the density of the atmosphere. The pressure on the surface of Venus is 92 times greater than that on Earth. Under the clouds of sulfuric acid lie hurricanes and thunderstorms that never subside here.

Terrestrial planets: Earth and Mars

Earth- the largest of the inner group and the only planet in the system suitable for life. The Earth's atmosphere contains nitrogen, oxygen, carbon dioxide, argon, and water vapor. The surface is protected by an ozone layer and a magnetic field just enough for life to be born on it in the form in which it exists now. Earth's satellite is the Moon.

Mars closes the four terrestrial planets. The planet has a very thin atmosphere, a surface with craters, a topography with valleys, deserts, extinct volcanoes and polar glaciers. Including the huge Olympus volcano, which is the largest peak on the planets of the solar system - 21.2 km. It has been proven that the surface of the planet was once . But today there is only ice and dust devils.

The location of the planets in the solar system

Gas group planets

Jupiter- the largest planet in the solar system. It is more than 300 times heavier than the Earth, although it consists of gases: hydrogen and helium. Jupiter has quite powerful radiation to influence nearby objects. It has the most satellites - 67. Some of them are quite large bodies, different in structure.

Jupiter itself is covered in liquid. On its surface there are noticeable many stripes of light and dark colors moving parallel to the equator. These are clouds. Winds of up to 600 km/h rage beneath them. For several centuries, astronomers have been observing a red spot on the surface of Jupiter larger than the Earth, which is a giant storm.

Attention! Jupiter rotates around its axis faster than all the planets in the solar system. A day here is less than 10 hours.

Saturn popularly known as the ringed planet. They consist of ice and dust particles. The planet's atmosphere is dense, almost entirely consisting of hydrogen (more than 96%) and helium. Saturn has more than 60 open moons. The surface density is the smallest among the planets of the system, less than the density of water.

Uranus and Neptune They are classified as ice giants because they have a lot of ice on their surface. And the atmosphere consists of hydrogen and helium. Neptune is very stormy, Uranus is much calmer. As the most distant planet in the system, Neptune has the longest year - almost 165 Earth years. Behind Neptune is the little-studied Kuiper Belt, a cluster of small bodies of various structures and sizes. It is considered the outskirts of the solar system.

Space: video

> Planets of the Solar System in order

Explore planets of the solar system in order. High quality photos, the location of the Earth and a detailed description of each planet around the Sun: from Mercury to Neptune.

Let's look at the planets of the solar system in order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

What is a planet?

According to the criteria established by the IAU in 2006, an object is considered a planet:

• on an orbital path around the Sun;
• has sufficient massiveness for hydrostatic balance;
• cleared the surrounding area of ​​foreign bodies;

This led to the fact that Pluto could not meet the last point and moved into the ranks of dwarf planets. For the same reason, Ceres is no longer an asteroid, but has joined Pluto.

But there are also trans-Neptunian objects, which are considered a subcategory of dwarf planets and are called the plutoid class. These are celestial bodies rotating beyond the orbit of Neptune. These include Ceres, Pluto, Haumea, Eris and Makemake.

Planets of the Solar System in order

Let's now study our planets of the solar system in order of increasing distance from the Sun with high quality photos.

Mercury

Mercury is the first planet from the Sun, 58 million km away. Despite this, it is not considered the hottest planet.

Now considered the tiniest planet, second in size to its moon Ganymede.

• Diameter: 4,879 km
• Mass: 3.3011 × 10 23 kg (0.055 Earth).
• Length of year: 87.97 days.
• Length of day: 59 days.
• Included in the category of terrestrial planets. The crater surface resembles the Earth's Moon.
• If you weigh 45 kg on Earth, you will gain 17 kg on Mercury.
• No satellites.
• Temperature ranges from -173 to 427 °C (-279 to 801 degrees Fahrenheit)
• Only 2 missions were sent: Mariner 10 in 1974-1975. and MESSENGER, which flew past the planet three times before entering orbit in 2011.

Venus

It is 108 million km distant from the Sun and is considered an earthly sister because it is similar in parameters: 81.5% of the mass, 90% of the earth’s area and 86.6% of its volume.

Due to its thick atmospheric layer, Venus has become the hottest planet in the solar system, with temperatures rising to 462°C.

• Diameter: 12104 km.
• Mass: 4.886 x 10 24 kg (0.815 earth)
• Length of the year: 225 days.
• Length of day: 243 days.
• Temperature heating: 462°C.
• The dense and toxic atmospheric layer is filled with carbon dioxide (CO2) and nitrogen (N2) with drops of sulfuric acid (H2SO4).
• No satellites.
• Retrograde rotation is characteristic.
• If you weigh 45 kg on Earth, you will gain 41 kg on Venus.
• It was called the Morning and Evening Star because it is often brighter than any other object in the sky and is usually visible at dawn or dusk. Often even mistaken for a UFO.
• Sent over 40 missions. Magellan mapped 98% of the planet's surface in the early 1990s.

Earth

The Earth is our home, living at a distance of 150 million km from the star. So far the only world that has life.

• Diameter: 12760 km.
• Weight: 5.97 x 10 24 kg.
• Length of the year: 365 days.
• Length of day: 23 hours, 56 minutes and 4 seconds.
• Surface Heat: Average - 14°C, with ranges from -88°C to 58°C.
• The surface is constantly changing, and 70% is covered by oceans.
• There is one satellite.
• Atmospheric composition: nitrogen (78%), oxygen (21%) and other gases (1%).
• The only world with life.

Mars

The Red Planet, 288 million km distant. Received its second name because of the reddish tint created by iron oxide. Mars resembles Earth due to its axial rotation and tilt, which creates seasonality.

There are also many familiar surface features, such as mountains, valleys, volcanoes, deserts and ice caps. The atmosphere is thin, so the temperature drops to -63 o C.

• Diameter: 6787 km.
• Mass: 6.4171 x 10 23 kg (0.107 Earth).
• Length of the year: 687 days.
• Length of day: 24 hours and 37 minutes.
• Surface Temperature: Average - approximately -55°C with a range of -153°C to +20°C.
• Belongs to the category of terrestrial planets. The rocky surface has been affected by volcanoes, asteroid attacks and atmospheric effects such as dust storms.
• The thin atmosphere consists of carbon dioxide (CO2), nitrogen (N2) and argon (Ar). If you weigh 45 kg on Earth, you will gain 17 kg on Mars.
• There are two tiny moons: Phobos and Deimos.
• Called the Red Planet because iron minerals in the soil oxidize (rust).
• More than 40 spacecraft have been sent.

Jupiter

Jupiter is the largest planet in the solar system, living at a distance of 778 million km from the Sun. It is 317 times larger than the Earth and 2.5 times larger than all the planets together. Represented by hydrogen and helium.

The atmosphere is considered the most intense, where the wind accelerates to 620 km/h. There are also amazing auroras that almost never stop.

• Diameter: 428400 km.
• Mass: 1.8986 × 10 27 kg (317.8 Earth).
• Length of year: 11.9 years.
• Length of day: 9.8 hours.
• Temperature reading: -148°C.
• There are 67 known moons, and another 17 moons await confirmation of their discovery. Jupiter resembles a mini-system!
• In 1979, Voyager 1 spotted a faint ring system.
• If you weigh 45 kg on Earth, you will get 115 kg on Jupiter.
• The Great Red Spot is a large-scale storm (larger than the Earth) that has not stopped for hundreds of years. In recent years there has been a downward trend.
• Many missions have flown past Jupiter. The last one arrived in 2016 - Juno.

Saturn

Distant 1.4 billion km. Saturn is a gas giant with a gorgeous ring system. There are layers of gas concentrated around a solid core.

• Diameter: 120500 km.
• Mass: 5.66836 × 10 26 kg (95.159 Earth).
• Length of year: 29.5 years.
• Length of day: 10.7 hours.
• Temperature mark: -178 °C.
• Atmospheric composition: hydrogen (H2) and helium (He).
• If you weigh 45 kg on Earth, you will get about 48 kg on Saturn.
• There are 53 known satellites with an additional 9 awaiting confirmation.
• 5 missions were sent to the planet. Since 2004, Cassini has been studying the system.

Uranus

Lives at a distance of 2.9 billion km. It belongs to the class of ice giants due to the presence of ammonia, methane, water and hydrocarbons. Methane also creates a blue appearance.

Uranus is the frostiest planet in the system. The seasonal cycle is quite bizarre, as it lasts 42 years for each hemisphere.

• Diameter: 51120 km.
• Length of year: 84 years.
• Length of day: 18 hours.
• Temperature mark: -216°C.
• Most of the planetary mass is a hot, dense liquid of “icy” materials: water, ammonia and methane.
• Atmospheric composition: hydrogen and helium with a small admixture of methane. Methane causes a blue-green hue.
• If you weigh 45 kg on Earth, you will get 41 kg on Uranus.
• There are 27 satellites.
• There is a weak ring system.
• The only ship sent to the planet was Voyager 2.

Neptune

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 we take it as a full-fledged celestial 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 always turned the same side to the Sun, since periods of its visibility from 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 on the surface, 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 by 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, observations through a telescope indicate 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 the Mariner 4 spacecraft arrived at Mars in 1965, many scientists were shocked to see photographs of the murky, 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, with four large moons 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

The fifth planet from the Sun and the largest planet in 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 larger quantities than on the Sun.

There is an opinion that one of the four gas giants is actually a failed star. This theory is also supported by the largest number of satellites, of which Jupiter has many - 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. In comparison with other planets, it is most similar to the Sun in the composition of 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 arranged in order as follows:
1 - Mercury. The smallest real planet in the solar system
2 - Venus. The description of hell was taken from her: terrible heat, sulfur vapors and the eruptions of many volcanoes.
3 - Earth. The third planet in order from the Sun, our home.
4 - Mars. The most distant of the terrestrial planets in the Solar System.
Then there is the Main Asteroid Belt, where the dwarf planet Ceres and the minor planets Vesta, Pallas, and others are located.
Next in order are the four giant planets:
5 - Jupiter. The largest planet in the solar system.
6 - Saturn with its famous rings.
7 - Uranium. The coldest planet.
8 - Neptune. It is the farthest "real" planet in order from the Sun.
Here's what's more interesting:
9 - Pluto. A dwarf planet that is usually mentioned after Neptune. But Pluto's orbit is such that it is sometimes closer to the Sun than Neptune. For example, this was the case from 1979 to 1999.
No, Neptune and Pluto cannot collide :) - their orbits are such that they do not intersect.
The order of the planets of the solar system in the photo:

How many planets are there in the solar system

How many planets are there in the solar system? This is not so easy to answer. For a long time it was believed that there are nine planets in the solar system:
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

But, on August 24, 2006, Pluto ceased to be considered a planet. This was caused by the discovery of the planet Eris and other small planets of the solar system, in connection with which it was necessary to clarify which celestial bodies can be considered planets.
Several characteristics of “real” planets were identified and it turned out that Pluto does not fully satisfy them.
Therefore, Pluto was relegated to the category of dwarf planets, which includes, for example, Ceres, the former number 1 asteroid in the Main Asteroid Belt between Mars and Jupiter.

As a result, when trying to answer the question of how many planets are in the solar system, the situation became even more confused. Because in addition to the “real” ones, dwarf planets have now also appeared.
But there are also small planets, which were called large asteroids. For example Vesta, asteroid number 2 in the mentioned Main Asteroid Belt.
Recently, the same Eris, Make-Make, Haumea and several other small ones have been discovered planets of the solar system, data about which is insufficient and it is unclear whether they should be considered dwarf or small planets. Not to mention that some small asteroids are mentioned in the literature as minor planets! For example, the asteroid Icarus, whose size is only about 1 kilometer, is often referred to as a minor planet...
Which of these bodies should be taken into account when answering the question “how many planets are there in the solar system”???
In general, “we wanted the best, but it turned out as always.”

It is curious that many astronomers and even ordinary people come out “in defense” of Pluto, continuing to consider it a planet, sometimes organizing small demonstrations and diligently promoting this idea on the Internet (mainly abroad).

Therefore, when answering the question “how many planets are there in the solar system,” the easiest way is to briefly say “eight” and not even try to discuss anything... otherwise you will immediately discover that there is simply no exact answer :)

Giant planets - the largest planets in the solar system

There are four giant planets in the solar system: Jupiter, Saturn, Uranus and Neptune. Because these planets are located outside the Main Asteroid Belt, they are called the "outer" planets of the solar system.
In terms of size, two pairs clearly stand out among these giants.
The largest giant planet is Jupiter. Saturn is quite a bit inferior to him.
And Uranus and Neptune are sharply smaller than the first two planets and they are located further from the Sun.
Look at the comparative sizes of the giant planets relative to the Sun:

The giant planets protect the inner planets of the solar system from asteroids.
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 can learn more about the largest planets in the solar system here:

Terrestrial planets

The terrestrial planets are the four planets of the solar system that are similar in size and composition: Mercury, Venus, Earth and Mars.
Since one of them is the Earth, all these planets are classified as the terrestrial group. Their sizes are very similar, and Venus and Earth are generally almost the same. Their temperatures are relatively high, which is explained by their proximity to the Sun. All four planets are formed by rocks, while the giant planets are gas and ice worlds.

Mercury is the closest planet to the Sun and the smallest planet in the Solar System.
It is generally accepted that Mercury is very hot. Yes, that's right, the temperature on the sunny side can reach +427°C. But, there is almost no atmosphere on Mercury, so on the night side it can reach -170°C. And at the poles, due to the low Sun, a layer of underground permafrost is generally assumed...

Venus. For a long time it was considered the “sister” of the Earth, until Soviet research stations descended on its surface. It turned out to be real hell! Temperature +475°C, pressure of almost a hundred atmospheres and an atmosphere of toxic compounds of sulfur and chlorine. To colonize it, you will have to try very hard...

Mars. The famous red planet. It is the most distant terrestrial planet in the solar system.
Like Earth, Mars has satellites: Phobos and Deimos
It is generally a cold, rocky and dry world. Only at the equator at noon can it warm up to +20°C, the rest of the time there is severe frost, down to -153°C at the poles.
The planet does not have a magnetosphere and cosmic radiation mercilessly irradiates the surface.
The atmosphere is very rarefied and not suitable for breathing, however, its density is enough for powerful dust storms to sometimes occur on Mars.
Despite all the shortcomings. Mars is the most promising planet for colonization in the solar system.

More information about the terrestrial planets is described in the article The largest planets of the solar system

The largest planet in the solar system

The largest planet in the solar system is Jupiter. It is the fifth planet from the Sun, its orbit lies beyond the Main Asteroid Belt. Look at the size comparison between Jupiter and Earth:
Jupiter's diameter is 11 times larger than Earth's, and its mass is 318 times greater. Due to the large size of the planet, parts of its atmosphere rotate at different speeds, so the belts of Jupiter are clearly visible in the image. Below on the left you can see the famous Great Red Spot of Jupiter - a huge atmospheric vortex that has been observed for several centuries.

The smallest planet in the solar system

Which planet is the smallest planet in the solar system? This is not such a simple question...
Today it is generally accepted that the smallest planet in the solar system is Mercury, which we mentioned a little above. But, you already know that until August 24, 2006, Pluto was considered the smallest planet in the solar system.

More attentive readers may recall that Pluto is a dwarf planet. And there are five of them known. The smallest dwarf planet is Ceres, with a diameter of about 900 km.
But that's not all...

There are also so-called minor planets, the size of which starts at only 50 meters. Both the 1-kilometer Icarus and the 490-kilometer Pallas fall under this definition. It is clear that there are many of them, and it is difficult to choose the smallest one due to the complexity of observations and calculation of sizes. So, when answering the question “what is the name of the smallest planet in the solar system,” it all depends on what exactly is meant by the word “planet.”