The science

We all know from childhood that at the center of our solar system is the Sun, around which the four closest terrestrial planets revolve, including Mercury, Venus, Earth and Mars. They are followed by four gas giant planets: Jupiter, Saturn, Uranus and Neptune.

After Pluto ceased to be considered a planet in the solar system in 2006 and became a dwarf planet, the number of main planets was reduced to 8.

Although many people know general structure, there are many myths and misconceptions regarding the solar system.

Here are 10 facts you might not know about the solar system.

1. The hottest planet is not closest to the Sun

Many people know that Mercury is the planet closest to the Sun, whose distance is almost two times less than the distance from the Earth to the Sun. It's no wonder that many people believe that Mercury is the hottest planet.



In fact Venus is the hottest planet in the solar system- the second planet close to the Sun, where the average temperature reaches 475 degrees Celsius. This is enough to melt tin and lead. In the same time Maximum temperature on Mercury is about 426 degrees Celsius.

But due to the lack of an atmosphere, the surface temperature of Mercury can vary by hundreds of degrees, while the carbon dioxide on the surface of Venus maintains a virtually constant temperature at any time of the day or night.

2. The edge of the solar system is a thousand times further from Pluto

We are used to thinking that the solar system extends to the orbit of Pluto. Today, Pluto is not even considered a major planet, but this idea remains in the minds of many people.



Scientists have discovered many objects orbiting the Sun that are much further than Pluto. These are the so-called trans-Neptunian or Kuiper belt objects. The Kuiper Belt extends over 50-60 astronomical units (An astronomical unit, or the average distance from the Earth to the Sun, is 149,597,870,700 m).

3. Almost everything on planet Earth is a rare element

The earth is mainly composed of iron, oxygen, silicon, magnesium, sulfur, nickel, calcium, sodium and aluminum.



Although all of these elements have been found in different places throughout the universe, they are only traces of elements that dwarf the abundance of hydrogen and helium. Thus, the Earth is mostly composed of rare elements. This does not indicate any special place on planet Earth, since the cloud from which the Earth was formed contained a large number of hydrogen and helium. But because they are light gases, they were carried into space by the sun's heat as the Earth formed.

4. The solar system has lost at least two planets

Pluto was originally considered a planet, but due to its very small size (much smaller than our Moon), it was renamed a dwarf planet. Astronomers also the planet Vulcan was once believed to exist, which is closer to the Sun than Mercury. Its possible existence was discussed 150 years ago to explain some features of Mercury's orbit. However, later observations ruled out the possibility of Vulcan's existence.



In addition, recent research has shown that it may someday there was a fifth giant planet, similar to Jupiter, which orbited the Sun, but was thrown out of the Solar System due to gravitational interaction with other planets.

5. Jupiter has the largest ocean of any planet

Jupiter, which orbits in cold space five times farther from the sun than planet Earth, was able to hold much more high level hydrogen and helium during formation than our planet.



One could even say that Jupiter is mainly composed of hydrogen and helium. Considering the mass of the planet and chemical composition, as well as the laws of physics, under cold clouds, an increase in pressure should lead to the transition of hydrogen into a liquid state. That is, on Jupiter there should be deepest ocean of liquid hydrogen.

According to computer models, this planet not only has the largest ocean in the solar system, its depth is approximately 40,000 km, that is, equal to the circumference of the Earth.

6. Even the smallest bodies in the solar system have satellites

It was once believed that only large objects such as planets could have natural satellites or moons. The existence of moons is sometimes even used to determine what a planet actually is. It seems counterintuitive that small cosmic bodies could have enough gravity to hold a satellite. After all, Mercury and Venus don't have any, and Mars only has two tiny moons.



But in 1993, the Galileo interplanetary station discovered a Dactyl satellite near the asteroid Ida, only 1.6 km wide. Since then it has been found moons orbiting about 200 other small planets, which made defining a “planet” much more difficult.

7. We live inside the Sun

We usually think of the Sun as a huge hot ball of light located at a distance of 149.6 million km from Earth. In fact The Sun's outer atmosphere extends much further than the visible surface.



Our planet orbits within its thin atmosphere, and we can see this when gusts of solar wind cause the aurora to appear. In this sense, we live inside the Sun. But the solar atmosphere does not end on Earth. The aurora can be observed on Jupiter, Saturn, Uranus and even distant Neptune. The outermost region of the solar atmosphere is the heliosphere extends over at least 100 astronomical units. This is about 16 billion kilometers. But since the atmosphere is drop-shaped due to the movement of the Sun in space, its tail can reach from tens to hundreds of billions of kilometers.

8. Saturn isn't the only planet with rings

While Saturn's rings are by far the most beautiful and easy to observe, Jupiter, Uranus and Neptune also have rings. While Saturn's bright rings are made of icy particles, Jupiter's very dark rings are mostly dust particles. They may contain minor fragments of disintegrated meteorites and asteroids and possibly particles of the volcanic moon Io.



Uranus's ring system is slightly more visible than Jupiter's and may have formed after the collision of small moons. Neptune's rings are faint and dark, just like Jupiter's. Faint rings of Jupiter, Uranus and Neptune impossible to see through small telescopes from Earth, because Saturn became most famous for its rings.

Contrary to popular belief, there is a body in the solar system with an atmosphere essentially similar to that of Earth. This is Saturn's moon Titan.. It is larger than our Moon and is close in size to the planet Mercury. Unlike the atmosphere of Venus and Mars, which are much thicker and thinner, respectively, than that of Earth, and consist of carbon dioxide, Titan's atmosphere is mostly nitrogen.



The Earth's atmosphere is approximately 78 percent nitrogen. The similarity with the Earth's atmosphere, and especially the presence of methane and other organic molecules, led scientists to believe that Titan could be considered an analogue early earth, or there is some kind of biological activity present. For this reason, Titan is considered best place in the solar system to search for signs of life.


The planetary system, called the Solar system, includes the central luminary - the Sun, as well as many space objects of different sizes and status. This system was formed as a result of the compression of a cloud of dust and gas more than 4 billion years ago. Main part of the mass solar planet centered on the Sun. Eight large planets orbit the star in nearly circular orbits located within a flat disk.

The inner planets of the solar system are considered to be Mercury, Venus, Earth and Mars (in order of distance from the Sun). These celestial bodies are classified as terrestrial planets. Next come the largest planets - Jupiter and Saturn. The series is completed by Uranus and Neptune, located farthest from the center. Orbiting the dwarf planet Pluto at the very edge of the system.

Earth is the third planet in the solar system. Like other large bodies, it revolves around the Sun in a closed orbit, subject to the gravitational force of the star. The sun attracts celestial bodies to itself, preventing them from approaching the center of the system or flying away into space. Together with the planets, smaller bodies - meteors, comets, asteroids - rotate around the central star.

Features of planet Earth

The average distance from Earth to the center of the solar system is 150 million km. The location of the third planet turned out to be extremely favorable from the point of view of the emergence and development of life. The Earth receives a tiny amount of heat from the Sun, but this energy is quite enough for living organisms to exist within the planet. On Venus and Mars, the closest neighbors of the Earth, conditions in this regard are less favorable.

Among the planets of the so-called terrestrial group, the Earth stands out for its greatest density and size. The composition of the local atmosphere, which contains free oxygen, is unique. The presence of a powerful hydrosphere also gives the Earth its originality. These factors have become one of the main conditions for the existence of biological forms. Scientists believe that the formation internal structure The Earth still continues due to tectonic processes occurring in its depths.

The Moon, its natural satellite, is located in close proximity to the Earth. This is the only space object that people have visited to date. The average distance between the Earth and its satellite is about 380 thousand km. The lunar surface is covered with dust and rocky debris. There is no atmosphere on the Earth's satellite. It is possible that in the distant future the territory of the Moon will be developed by earthly civilization.

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 strong impact 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%) for a long time hid the surface from human eyes. Venus is very hot (+460°C), but unlike Mercury, the main reason for this is 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 most major 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 most long 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

The solar system is a group of planets revolving in specific orbits around a bright star - the Sun. This star is the main source of heat and light in the solar system.

It is believed that our planetary system was formed as a result of the explosion of one or more stars and this happened about 4.5 billion years ago. At first, the solar system was an accumulation of gas and dust particles, however, over time and under the influence of its own mass, the Sun and other planets arose.

Planets of the Solar System

At the center of the solar system is the Sun, around which eight planets move in their orbits: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Until 2006, Pluto also belonged to this group of planets; it was considered the 9th planet from the Sun, however, due to its significant distance from the Sun and small size, it was excluded from this list and called a dwarf planet. More precisely, it is one of several dwarf planets in the Kuiper belt.

All of the above planets are usually divided into two large groups: the terrestrial group and the gas giants.

The terrestrial group includes such planets as: Mercury, Venus, Earth, Mars. They are distinguished by their small size and rocky surface, and in addition, they are located closest to the Sun.

Gas giants include: Jupiter, Saturn, Uranus, Neptune. They are characterized by big sizes and the presence of rings representing ice dust and rocky chunks. These planets consist mainly of gas.

Sun

The Sun is the star around which all the planets and satellites in the solar system revolve. It consists of hydrogen and helium. The Sun is 4.5 billion years old and is only halfway through its life cycle, gradually increases in size. Now the diameter of the Sun is 1,391,400 km. In just the same number of years, this star will expand and reach the orbit of the Earth.

The sun is the source of heat and light for our planet. Its activity increases or becomes weaker every 11 years.

Due to the extremely high temperatures on its surface, a detailed study of the Sun is extremely difficult, but attempts to launch a special device as close to the star as possible continue.

Terrestrial group of planets

Mercury

This planet is one of the smallest in the solar system, its diameter is 4,879 km. In addition, it is closest to the Sun. This proximity predetermined a significant temperature difference. average temperature on Mercury in daytime is +350 degrees Celsius, and at night - -170 degrees.

If we take the Earth year as a guide, Mercury makes a full revolution around the Sun in 88 days, and one day there lasts 59 Earth days. It was noticed that this planet can periodically change the speed of its rotation around the Sun, its distance from it and its position.

There is no atmosphere on Mercury; therefore, it is often attacked by asteroids and leaves behind a lot of craters on its surface. Sodium, helium, argon, hydrogen, and oxygen were discovered on this planet.

A detailed study of Mercury is very difficult due to its close proximity to the Sun. Sometimes Mercury can be seen from Earth with the naked eye.

According to one theory, it is believed that Mercury was previously a satellite of Venus, however, this assumption has not yet been proven. Mercury does not have its own satellite.

Venus

This planet is the second from the Sun. In size it is close to the diameter of the Earth, the diameter is 12,104 km. In all other respects, Venus differs significantly from our planet. A day here lasts 243 Earth days, and a year lasts 255 days. The atmosphere of Venus is 95% carbon dioxide, which creates a greenhouse effect on its surface. This results in an average temperature on the planet of 475 degrees Celsius. The atmosphere also contains 5% nitrogen and 0.1% oxygen.

Unlike the Earth, most of whose surface is covered with water, there is no liquid on Venus, and almost the entire surface is occupied by solidified basaltic lava. According to one theory, there used to be oceans on this planet, however, as a result of internal heating, they evaporated, and the vapors were carried away by the solar wind into outer space. Near the surface of Venus, weak winds blow, however, at an altitude of 50 km their speed increases significantly and amounts to 300 meters per second.

Venus has many craters and hills that resemble the earth's continents. The formation of craters is associated with the fact that the planet previously had a less dense atmosphere.

A distinctive feature of Venus is that, unlike other planets, its movement occurs not from west to east, but from east to west. It can be seen from Earth even without the help of a telescope after sunset or before sunrise. This is due to the ability of its atmosphere to reflect light well.

Venus has no satellite.

Earth

Our planet is located at a distance of 150 million km from the Sun, and this allows us to create on its surface a temperature suitable for the existence of liquid water, and, therefore, for the emergence of life.

Its surface is 70% covered with water, and it is the only planet to contain such an amount of liquid. It is believed that many thousands of years ago, steam contained in the atmosphere created the temperature on the Earth's surface necessary for the formation of water in liquid form, and solar radiation contributed to photosynthesis and the birth of life on the planet.

The peculiarity of our planet is that under the earth’s crust there are huge tectonic plates, which, moving, collide with each other and lead to changes in the landscape.

The diameter of the Earth is 12,742 km. An earthly day lasts 23 hours 56 minutes 4 seconds, and a year lasts 365 days 6 hours 9 minutes 10 seconds. Its atmosphere is 77% nitrogen, 21% oxygen and a small percentage of other gases. None of the atmospheres of other planets in the solar system has such an amount of oxygen.

According to scientists, the age of the Earth is 4.5 billion years, approximately the same age that its only satellite, the Moon, has existed. It is always turned to our planet with only one side. There are many craters, mountains and plains on the surface of the Moon. It reflects sunlight very weakly, so it is visible from Earth in the pale moonlight.

Mars

This planet is the fourth from the Sun and is 1.5 times more distant from it than the Earth. The diameter of Mars is smaller than Earth's and is 6,779 km. The average air temperature on the planet ranges from -155 degrees to +20 degrees at the equator. The magnetic field on Mars is much weaker than that of Earth, and the atmosphere is quite thin, which allows solar radiation to unimpededly affect the surface. In this regard, if there is life on Mars, it is not on the surface.

When surveyed with the help of Mars rovers, it was found that there are many mountains on Mars, as well as dried up river beds and glaciers. The surface of the planet is covered with red sand. It is iron oxide that gives Mars its color.

One of the most frequent events on the planet are dust storms, which are voluminous and destructive. It was not possible to detect geological activity on Mars, however, it is reliably known that significant geological events previously occurred on the planet.

The atmosphere of Mars consists of 96% carbon dioxide, 2.7% nitrogen and 1.6% argon. Oxygen and water vapor are present in minimal quantities.

A day on Mars is similar in length to those on Earth and is 24 hours 37 minutes 23 seconds. A year on the planet lasts twice as long as on Earth - 687 days.

The planet has two satellites Phobos and Deimos. They have small sizes and an uneven shape reminiscent of asteroids.

Sometimes Mars is also visible from Earth with the naked eye.

Gas giants

Jupiter

This planet is the largest in the solar system and has a diameter of 139,822 km, which is 19 times larger than Earth. A day on Jupiter lasts 10 hours, and a year is approximately 12 Earth years. Jupiter is mainly composed of xenon, argon and krypton. If it were 60 times larger, it could become a star due to a spontaneous thermonuclear reaction.

The average temperature on the planet is -150 degrees Celsius. The atmosphere consists of hydrogen and helium. There is no oxygen or water on its surface. There is an assumption that there is ice in the atmosphere of Jupiter.

Jupiter has a huge number of satellites - 67. The largest of them are Io, Ganymede, Callisto and Europa. Ganymede is one of the largest moons in the Solar System. Its diameter is 2634 km, which is approximately the size of Mercury. In addition, a thick layer of ice can be seen on its surface, under which there may be water. Callisto is considered the most ancient of the satellites, since it is its surface that has the largest number of craters.

Saturn

This planet is the second largest in the solar system. Its diameter is 116,464 km. It is most similar in composition to the Sun. A year on this planet lasts quite a long time, almost 30 Earth years, and a day lasts 10.5 hours. The average surface temperature is -180 degrees.

Its atmosphere consists mainly of hydrogen and a small amount of helium. In her upper layers Thunderstorms and auroras often occur.

Saturn is unique in that it has 65 moons and several rings. The rings are made up of small particles of ice and rock formations. Ice dust perfectly reflects light, so Saturn's rings are very clearly visible through a telescope. However, it is not the only planet with a diadem; it is just less noticeable on other planets.

Uranus

Uranus is the third largest planet in the solar system and the seventh from the Sun. It has a diameter of 50,724 km. It is also called the “ice planet”, as the temperature on its surface is -224 degrees. A day on Uranus lasts 17 hours, and a year lasts 84 Earth years. Moreover, summer lasts as long as winter - 42 years. This a natural phenomenon This is due to the fact that the axis of that planet is located at an angle of 90 degrees to the orbit and it turns out that Uranus seems to be “lying on its side.”

Uranus has 27 moons. The most famous of them are: Oberon, Titania, Ariel, Miranda, Umbriel.

Neptune

Neptune is the eighth planet from the Sun. It is similar in composition and size to its neighbor Uranus. The diameter of this planet is 49,244 km. A day on Neptune lasts 16 hours, and a year is equal to 164 Earth years. Neptune is an ice giant and for a long time it was believed that no weather phenomena occur on its icy surface. However, it was recently discovered that Neptune has raging vortices and wind speeds that are the highest among the planets in the solar system. It reaches 700 km/h.

Neptune has 14 moons, the most famous of which is Triton. It is known to have its own atmosphere.

Neptune also has rings. This planet has 6 of them.

Interesting facts about the planets of the solar system

Compared to Jupiter, Mercury seems like a dot in the sky. These are the actual proportions in the solar system:

Venus is often called the Morning and Evening Star, since it is the first of the stars visible in the sky at sunset and the last to disappear from visibility at dawn.

An interesting fact about Mars is the fact that methane was found on it. Due to the thin atmosphere, it constantly evaporates, which means that the planet has a constant source of this gas. Such a source could be living organisms inside the planet.

There are no seasons on Jupiter. The biggest mystery is the so-called “Great Red Spot”. Its origin on the surface of the planet has not yet been fully elucidated. Scientists suggest that it was formed by a huge hurricane, which has been rotating at very high speed for several centuries.

An interesting fact is that Uranus, like many planets in the solar system, has its own ring system. Due to the fact that the particles that make up them do not reflect light well, the rings could not be detected immediately after the discovery of the planet.

Neptune has a rich blue color, so it was named after the ancient Roman god - the master of the seas. Due to its distant location, this planet was one of the last to be discovered. At the same time, its location was calculated mathematically, and after time it was able to be seen, and precisely in the calculated place.

Light from the Sun reaches the surface of our planet in 8 minutes.

The solar system, despite its long and careful study, still conceals many mysteries and secrets that have yet to be revealed. One of the most fascinating hypotheses is the assumption of the presence of life on other planets, the search for which is actively continuing.

Previously, any planet was called cosmic body, orbiting a star, emitting light that is reflected by that star, 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. Please note that the Sun is indicated here, which is a star, and the Moon is a satellite of our Earth. The earth is not included in this list because the Greeks considered it the center of everything.

In the 15th century, Copernicus discovered that the center of the system was the Sun, not the Earth. He laid out his statements in his work “On the Revolution of the Celestial Spheres.” The Moon and Sun were removed from the list, and 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, more planet doesn't count.

On this moment researchers give a new meaning to the word “planet”, namely: it is a celestial body that satisfies 4 conditions:

  • The body must rotate around the star.
  • Have a spherical or approximately spherical 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 near its 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 orbit the sun. 4.5 billion years ago, condensations of clouds of stellar matter began to form in the Galaxy. The gases heated up and radiated heat. As a result of an increase in temperature and density, nuclear reactions began, hydrogen turned into helium. This is how the most powerful source of energy arose - the Sun. This process took tens of millions of years. Planets with satellites were created. The formation of the solar system ended completely about 4 billion years ago.

Today, 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 composed of hydrogen and helium. The planets have 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, followed by Neptune. Before characterizing the planets of the Solar System, we need to talk about its main object - the Sun. This is the star through which all living and nonliving 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 core temperature is 13 million degrees Kelvin, and at the surface - 5 thousand degrees Kelvin (4727 degrees Celsius). In the Milky Way galaxy, the Sun is one of the largest and brightest 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 every 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 composed mainly of helium and is blown by wind from the Sun. Temperatures can reach +440 degrees Celsius. The planet completes a revolution around the Sun in 88 Earth days. A day on the planet is equal to 176 Earth hours.

Venus

Venus is the second planet from the Sun. Its dimensions are close to the size of the Earth. The planet has no satellites. The atmosphere consists of carbon dioxide with admixtures of nitrogen and oxygen. The air pressure is 90 atmospheres, which is 35 times more than on Earth. Venus is called the hottest planet because its dense atmosphere, carbon dioxide, proximity to the Sun and the greenhouse effect create very high temperatures on the planet's surface. It can reach 460 degrees Celsius. Venus can be seen from the surface of the Earth. This is the brightest cosmic object after the Moon and the Sun.

Earth

The only planet suitable for life. Maybe it exists on other planets, but no one can say this with certainty yet. It is the largest in its group in terms of mass, density and size. Its age is more than 4 billion years. Life began here more than 3 billion years ago. Earth's satellite is the Moon. The atmosphere on the planet is radically different from others. Most of it consists of nitrogen. This also includes carbon dioxide, oxygen, water vapor and argon. The ozone layer and magnetic field make the level of solar and cosmic radiation less. 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 lower. Islands and continents occupy 29% of the planet's surface, and the rest is the World Ocean.

Mars

It is also called the “red planet” due to the presence of large amounts 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 thin 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 changes can reach 40 degrees. The presence of volcanoes and craters, deserts and valleys, and polar ice caps distinguishes Mars from other planets in the solar system. Also here is the most high mountain- the extinct Olympus volcano, which reached a height of 27 kilometers. Valles Marineris is the largest canyon among the planets. Its length is 4500 km and its 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 components of the planet are helium and hydrogen. Jupiter emits a lot of heat - 4 * 1017 W. To become a star like the Sun, it must reach 70 times its current mass. 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 hosts many vortices that have a brownish-red colored 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. The ring system, which consists of particles of ice 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 homogeneous and calm, which can be explained by a dense layer of fog. Saturn has enormous wind speeds, it can reach 1800 km per hour.

Uranus

This planet was discovered first using a telescope. Uranus is the only planet in the solar system that lies on its side and orbits the sun. Uranus has 27 moons, which are named after characters in 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 farthest 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. Most blow in the same direction strong winds Solar system, the speed of which reaches 2200 km per hour. Neptune and Uranus have similar compositions, 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. There is methane in the outer layers of the atmosphere, 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, they excluded Pluto from the list of planets.

Study the planets on the portal website - it’s very interesting.

Rotation of planets

All planets, in addition to their orbit, also rotate around their own axis. The period during which they make a full revolution is defined as an epoch. Most of the planets in the Solar System rotate in the same direction on the axis as the Sun, but Uranus and Venus rotate in the opposite direction. Scientists observe a big difference in the length of the day on the planets - Venus takes 243 Earth days to complete one revolution around its axis, while the gas giant planets need only a couple of hours. The rotation period of exoplanets is unknown, but their close proximity to the stars means that eternal day reigns on one side, and eternal night on the other.

Why are all the planets so different? Thanks to high temperature Closer to the star, the ice and gas evaporated very quickly. The giant planets failed to form, but an accumulation of metal particles occurred. Thus, Mercury was formed, which contains the largest amount of metals. The further 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 located closer to the center of the solar system are called the inner ones. 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 strict order. The largest one is closer to the Sun, respectively, the smallest one is further away. Our system has a more complex structure, because the planets are not arranged according to their mass. The sun makes up more than 99 percent of all objects in the system.