Our home in space is the Solar System - a star system made up of eight planets and part of the Milky Way galaxy. In the center is a star named the Sun. The solar system is four and a half billion years old. We live on the third planet from the sun. Do you know about other planets Solar system?! Now we will tell you a little about them.
Mercury - the smallest planet in the solar system. Its radius is 2440 km. The period of revolution around the Sun is 88 Earth days. During this time, Mercury manages to complete a revolution around its own axis only one and a half times. A day on Mercury lasts approximately 59 Earth days. The orbit of Mercury is one of the most unstable: there changes not only the speed of movement and its distance from the Sun, but also the position itself. There are no satellites.
Neptune - the eighth planet of the solar system. Located close enough to Uranus. The radius of the planet is 24547 km. A year on Neptune is 60190 days, that is, somewhere around 164 earth years... Has 14 satellites. It has an atmosphere in which the strongest wind was recorded - up to 260 m / s.
By the way, Neptune was discovered not through observation, but through mathematical calculations.
Uranus - the seventh planet in the solar system. Radius - 25267 km. The coldest planet - the surface temperature is -224 degrees. A year on Uranus is equal to 30,685 Earth days, that is, approximately 84 years. Day - 17 hours. Has 27 satellites.
Saturn - the sixth planet of the solar system. The radius of the planet is 57350 km. It is the second largest after Jupiter. A year on Saturn is equal to 10759 days, which is almost 30 Earth years. A day on Saturn is almost equal to a day on Jupiter - 10.5 Earth hours. The most similar to the Sun in the composition of chemical elements.
Has 62 satellites.
The main feature of Saturn is its rings. Their origin has not yet been established.
Jupiter - the fifth planet from the Sun. Is an largest planet Solar system. The radius of Jupiter is 69912 km. This is 19 times the size of the Earth. A year there lasts as much as 4333 Earth days, that is, almost incomplete 12 years. A day has a duration of about 10 Earth hours.
Jupiter has 67 satellites. The largest of them are Callisto, Ganymede, Io and Europa. Moreover, Ganymede is 8% larger than the size of Mercury, the smallest planet in our system and has an atmosphere.
Mars - the fourth planet of the solar system. Its radius is 3390 km, which is almost half the size of the Earth. A year on Mars is 687 Earth days. Has 2 satellites - Phobos and Deimos.
The atmosphere of the planet is rarefied. The water found in some areas of the surface suggests that some kind of primitive life on Mars was once or even exists now.
Venus - the second planet of the solar system. In terms of mass and radius, it is similar to the Earth. There are no satellites.
The atmosphere of Venus is almost entirely carbon dioxide. The percentage of carbon dioxide in the atmosphere is 96%, nitrogen is about 4%. Water vapor and oxygen are also present, but in very small amounts. Due to the fact that this atmosphere creates a greenhouse effect, the temperature on the planet's surface reaches 475 ° C. A day on Venus is equal to 243 Earth days. The year on Venus is 255 days.
Pluto Is a dwarf planet at the borders of the solar system, which is the dominant object in a distant system of 6 small cosmic bodies. The radius of the planet is 1195 km. Pluto's orbital period around the Sun is approximately 248 Earth years. A day on Pluto is equal to 152 hours. The mass of the planet is approximately 0.0025 of the mass of the Earth.
It is noteworthy that Pluto was excluded from the category of planets in 2006 due to the fact that there are objects in the Kuiper belt that are larger or equal in size to Pluto, which is why, even if it is taken as a full-fledged planet, then in this case it is necessary add Eris to this category - she is almost the same size as Pluto.
\u003e Planets of the solar system in order
Explore planets of the solar system in order... High quality photo, place of the Earth and detailed description every 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:
- staying on an orbital path around the sun;
- is robust enough for hydrostatic balance;
- cleared the surroundings of foreign bodies;
This led to the fact that Pluto could not meet the last point and went into the categories of dwarf planets. For the same reason, Ceres is no longer an asteroid, but has joined Pluto.
But there are also trans-Neptunian objects that are considered a subcategory of dwarf planets and are called the plutoid class. These are celestial bodies revolving beyond the orbit of Neptune. This includes Ceres, Pluto, Haumea, Eris, and Makemake.
The planets of the solar system in order
Let's now examine our planets in the solar system in order of increasing distance from the sun with a high quality photo.
Mercury
Mercury is the first planet from the Sun, at a distance of 58 million km. Despite this, it is not considered the hottest planet.
Now considered the smallest planet, inferior in size to the satellite Ganymede.
- Diameter: 4,879 km
- Mass: 3.3011 × 10 23 kg (0.055 Earth).
- Length of a year: 87.97 days.
- Length of a 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 get 17 kg on Mercury.
- There are no satellites.
- Temperature reading 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 located at a distance of 108 million km 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 the thick atmospheric layer, Venus has become the hottest planet in the solar system, where temperatures rise to 462 ° C.
- Diameter: 12104 km.
- Weight: 4.886 x 10 24 kg (0.815 earth)
- Length of the year: 225 days.
- Length of a day: 243 days.
- Temperature heating: 462 ° C.
- The dense and toxic atmosphere is filled with carbon dioxide (CO2) and nitrogen (N2) with droplets of sulfuric acid (H2SO4).
- There are no satellites.
- Retrograde rotation is characteristic.
- If you weigh 45 kg on Earth, you will get 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 seen at dawn or dusk. It is often even mistaken for a UFO.
- Over 40 missions have been sent. Magellan mapped 98% of the planet's surface in the early 1990s.
Land
Land - native homeliving at a distance of 150 million km from the star. So far, the only world that has life.
- Diameter: 12,760 km.
- Weight: 5.97 x 10 24 kg.
- Duration of the year: 365 days.
- Length of a day: 23 hours, 56 minutes and 4 seconds.
- Surface heating: medium - 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, distant 288 million km. Received the second name because of the reddish hue created by iron oxide. Mars resembles Earth due to its axial rotation and tilt, which shape 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 ° C.
- Diameter: 6787 km.
- Weight: 6.4171 x 10 23 kg (0.107 Earth).
- Length of the year: 687 days.
- Day length: 24 hours and 37 minutes.
- Surface temperature: Medium - about -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 is represented by carbon dioxide (CO2), nitrogen (N2) and argon (Ar). If you weigh 45 kg on Earth, you will get 17 kg on Mars.
- There are two tiny moons: Phobos and Deimos.
- It is called the Red Planet because the iron minerals in the soil are oxidized (rust).
- More than 40 spacecraft were 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 Earth and 2.5 times larger than all the planets combined. Represented by hydrogen and helium.
The atmosphere is considered the most intense, where the wind speeds up to 620 km / h. There are also some amazing auroras that practically never stop.
- Diameter: 428 400 km.
- Mass: 1.8986 × 10 27 kg (317.8 Earth).
- Length of a year: 11.9 years.
- Length of a day: 9.8 hours.
- Temperature index: -148 ° C.
- There are 67 known satellites, with 17 more moons awaiting confirmation of their discovery. Jupiter looks like a mini-system!
- In 1979, Voyager 1 noticed a weak ring system.
- If you weigh 45 kg on Earth, you 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 last years there is a downward trend.
- Many missions have flown past Jupiter. The last one arrived in 2016 - Juno.
Saturn
It is 1.4 billion km away. Saturn is a gas giant with a gorgeous ring system. There are gas layers concentrated around a solid core.
- Diameter: 120,500 km.
- Mass: 5.66836 × 10 26 kg (95.159 Earth).
- Length of a year: 29.5 years.
- Length of a day: 10.7 hours.
- Temperature mark: -178 ° С.
- Atmospheric composition: hydrogen (H2) and helium (He).
- If you weigh 45 kg on Earth, you will get about 48 kg on Saturn.
- Yes 53 famous satellite with an additional 9 pending confirmation.
- 5 missions were sent to the planet. Since 2004, Cassini has been involved in 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 coldest planet in the system. The seasonal cycle is quite bizarre, as it lasts 42 years for each hemisphere.
- Diameter: 51,120 km.
- Duration of the year: 84 years.
- Length of a day: 18 hours.
- Temperature mark: -216 ° С.
- Most of the planetary mass is represented by a hot dense liquid made of "ice" materials: water, ammonia and methane.
- Atmospheric composition: hydrogen and helium with a small admixture of methane. Methane produces a blue-green cast.
- If you weigh 45 kg on Earth, you get 41 kg on Uranus.
- There are 27 satellites.
- There is a weak ring system.
- The only ship was sent to the planet - Voyager 2.
Neptune
The planets of the solar system are arranged in order in the following sequence:
1 - Mercury. The smallest true planets in the solar system
2 - Venus. The description of hell was taken from her: the terrible heat, evaporation of sulfur and the eruption of many volcanoes.
3 - Earth. The third planet in order from the Sun, our home.
4 - Mars. The most distant of the terrestrial planets of the solar system.
Then the Main Asteroid Belt is located, where the dwarf planet Ceres and the minor planets Vesta, Pallas, etc. are located.
Further in order are four giant planets:
5 - Jupiter. The largest planet in the solar system.
6 - Saturn with its famous rings.
7 - Uranus. The coldest planet.
8 - Neptune. This is the farthest "real" planet in order from the Sun.
But further curious:
9 - Pluto. A dwarf planet commonly referred to 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 arrangement of the planets of the solar system in order in the photo: 
How many planets are in the solar system
How many planets are in the solar system? This is not an easy 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 signs of "real" planets have been identified, and it turns out that Pluto does not fully satisfy them.
Therefore, Pluto was transferred to the category of dwarf planets, which include, for example, Ceres - the former asteroid number 1 in the main asteroid belt between Mars and Jupiter.
As a result, when trying to answer the question how many planets are in the solar system, the state of affairs became even more confusing. Because besides "real" dwarf planets have now appeared.
But there are also small planets, which were called large asteroids. For example Vesta, asteroid number 2 in the aforementioned Main Asteroid Belt.
IN recent times the very same Eris, Make-Make, Haumeya and several other small planets of the solar system, data about which is insufficient and it is not clear what to consider them - dwarf or minor planets. Not to mention the fact that some small asteroids are mentioned in the literature as minor planets! For example, the asteroid Icarus, which is only about 1 kilometer in size, is often referred to as a minor planet ...
Which of these bodies should be considered when answering the question "How many planets are 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 are "in defense" of Pluto, continuing to consider it a planet, sometimes arrange small demonstrations and diligently promote this idea on the Web (mostly abroad).
Therefore, when answering the question "how many planets are in the solar system", the easiest way is to say shortly "eight" and not even try to discuss something ... otherwise you will immediately find that there is simply no exact answer :)
The giant planets are the largest planets in the solar system
There are four giant planets in the solar system: Jupiter, Saturn, Uranus and Neptune. Since these planets are located outside the main asteroid belt, they are called the "outer" planets of the solar system.
In size among these giants, two pairs are clearly distinguished.
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 farther from the Sun.
Look at comparative sizes giant planets relative to the Sun: 
The giant planets protect the inner planets of the solar system from asteroids.
If these bodies were not in the solar system, our Earth would be hundreds of times more likely to be subject to falling asteroids and comets!
How do the giant planets protect us from the falls of uninvited guests?
You can learn more about the largest planets of the solar system here:
Terrestrial planets
Terrestrial planets are the four planets of the solar system, similar in size and composition: Mercury, Venus, Earth and Mars. 
Since one of them is Earth, all these planets were attributed to the terrestrial group. Their sizes are very similar, and Venus and Earth are generally almost the same. Their temperatures are relatively high due to 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 it is very hot on Mercury. Yes, it is, the temperature on the sunny side can reach + 427 ° C. But, on Mercury, there is almost no atmosphere, so on the night side it can be up to -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! The temperature is + 475 ° C, the pressure is almost a hundred atmospheres and the atmosphere is made of poisonous compounds of sulfur and chlorine. To colonize it, you will have to try very hard ...
Mars. The famous red planet. It is the farthest of the terrestrial planets in the solar system.
Like Earth, Mars has moons: Phobos and Deimos
Basically it is a cold, rocky and dry world. Only at the equator at noon can it get warmer up to + 20 ° С, the rest of the time - a fierce frost, up to -153 ° С at the poles.
The planet has no magnetosphere and cosmic radiation mercilessly irradiates the surface.
The atmosphere is very rarefied and not suitable for breathing, nevertheless its density is enough for sometimes powerful dust storms to happen on Mars.
Despite all the flaws. Mars is the most promising planet for colonization in the solar system. 
Read more about the terrestrial planets 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 is behind the Main Asteroid Belt. Take a look at the size comparison between Jupiter and Earth: 
Jupiter's diameter is 11 times that of Earth, and its mass is 318 times greater. Due to the planet's large size, parts of its atmosphere rotate at different speeds, so Jupiter's belts are clearly visible in the image. At the bottom left is Jupiter's famous Great Red Spot - 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 as many as five of them. The smallest dwarf planet is Ceres, with a diameter of about 900 km.
But that's not all ...
There are also the so-called minor planets, the size of which starts from only 50 meters. The 1-kilometer Icarus and 490-kilometer Pallas also fall under this definition. It is clear that there are many of them, and the smallest one is difficult to choose 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".
Or tell your friends: PLANETSIn ancient times, people knew only five planets: Mercury, Venus, Mars, Jupiter and Saturn, only they can be seen with the naked eye.
Uranus, Neptune and Pluto were discovered with telescopes in 1781, 1846 and 1930. Long time astronomers studied planets by observing them from Earth. They determined that all the planets, except Pluto, move in circular orbits in the same plane and in the same direction, calculated the sizes of the planets and the distances from them to the Sun, formed their own idea of \u200b\u200bthe structure of the planets, even suggested that Venus and Mars could be similar to Earth, and possibly life exists on them.
The launch of unmanned space stations to the planets made it possible to significantly expand, and in many respects, revise the concept of planets: it became possible to see photographs of the surface, to study the soil and atmosphere of the planets.
Mercury.
Mercury is a small planet, slightly larger than the Moon. Its surface is also littered with craters from impacts with meteorites. No geological processes have erased these dents from his face. Inside, Mercury is cold. It moves around the Sun faster than other planets, and very slowly around its axis. Having walked around the Sun twice, Mercury only manages to turn around its axis three times. Because of this, the temperature on the sunny side of the planet exceeds 300 degrees, and darkness and fierce cold reign on the unlit side. Mercury has practically no atmosphere.
Venus.
Exploring Venus is not easy. It is enveloped in a thick layer of clouds, and under this serene exterior is a real hell, the pressure exceeds the earth's a hundred times, the temperature on the surface is about 500 degrees, which is caused by the "greenhouse effect". For the first time, the Soviet automatic station "Venera - 9" was able to transmit to the Earth images of the surface covered with lava and stones. In the conditions of Venus, the device launched to the planet's surface quickly fails, so American scientists decided to obtain data on the planet's relief in a different way.
The unmanned station "Magellan", orbiting Venus many times, probed the planet with radar, as a result, a comprehensive picture of the surface was obtained. In some places the relief of Venus is similar to that of the Earth, but, in general, the landscapes are strange: high mountainous round areas surrounded by mountain ranges 250 - 300 km across, the entire area of \u200b\u200bwhich is occupied by volcanoes; other volcanic formations resemble flat-topped cakes with steep edges. The planet's surface is indented by channels that were laid by lava. Traces of active volcanic activity are visible everywhere. Meteorite craters on the surface of Venus are distributed evenly, which means that its surface was formed at the same time. Scientists cannot explain how this could have happened, Venus seemed to boil and was flooded with lava. Now volcanic activity on the planet is not detected.
The atmosphere of Venus is not at all similar to that of Earth, it is mainly composed of carbon dioxide. The thickness of the gas shell of Venus, in comparison with the earth, is monstrously large. The cloud layer reaches 20 km. The presence of concentrated aqueous solution sulfuric acid. Sunlight does not reach the surface of Venus, twilight reigns there, there is a sulfur rain, the landscape is constantly illuminated with flashes of lightning. High in the atmosphere of the planet, constant winds are raging, which drive the clouds at a tremendous speed, the upper layer of the Venusian atmosphere makes a full revolution around the planet for four Earth days. Solid Venus, on the other hand, rotates very slowly on its axis and in a different direction than all other planets. Venus has no satellites.
Mars.
In the 20th century, the planet Mars was chosen by science fiction writers; in their novels, the Martian civilization was incomparably higher than the earthly one. The mysterious inaccessible Mars began to reveal its secrets when Soviet and American unmanned spacecraft were sent to study it.
Station "Mariner - 9", revolving around Mars, took pictures of all parts of the planet, which made it possible to create detailed map surface relief. Researchers have found traces of active geological processes on the planet: huge volcanoes, the largest of them, Olympus, 25 km high, and a huge fault in the Martian crust, called the Mariner Valley, which crosses an eighth of the planet.
Gigantic structures have been growing in the same place for billions of years, unlike the Earth with its drifting continents, the surface of Mars did not move. The geological structures of the Earth, in comparison with the Martian ones, are dwarfs. Are volcanoes active on Mars now? Scientists believe that geological activity on the planet is obviously a thing of the past.
Reddish rocky deserts prevail among the Martian landscapes. Light transparent clouds float above them in the pink sky. Blue sky becomes at sunset. The atmosphere of Mars is very thin. Every few years there are dust storms that capture almost the entire surface of the planet. A day on Mars lasts 24 hours 37 minutes, the inclination of the axis of rotation of Mars to the orbital plane is almost the same as that of the Earth, so the change of seasons on Mars is quite consistent with the change of seasons on Earth. The planet is poorly heated by the Sun, so the temperature of its surface does not exceed 0 degrees even on a summer day, and in winter, frozen carbon dioxide settles on the stones from a fierce cold, and the Polar Caps also mainly consist of it. No traces of life have yet been found.
Mars is visible from Earth as a reddish star, which is probably why it bears the name of Mars, the god of war. His two companions were named Phobos and Deimos, which translated from ancient Greek means "fear" and "horror". Satellites of Mars - space "stones" irregular shape... Phobos measures 18km x 22km, and Deimos measures 10km x16km.
The planets are giants.
In 1977, American scientists and engineers within the framework of the Voyager program launched an automatic interplanetary station towards Jupiter. Once every 175 years, Jupiter, Saturn, Neptune and Pluto are positioned in such a way relative to the Earth that a launched spacecraft can survey all of these planets in one flight. Scientists calculated that under certain conditions, a spacecraft, flying up to the planet, falls into a gravitational sling, the planet itself sends the device further to another planet. The calculations turned out to be correct. Earthlings could see these distant planets and their satellites with "eyes" space robots, unique information was transmitted to the Earth.
Jupiter.
Jupiter is the largest planet in the solar system. It does not have a solid surface and consists mainly of hydrogen and helium. Due to the high speed of rotation around its axis, it is noticeably compressed at the poles. Jupiter has a huge magnetic field, if it became visible, then from Earth it would look the size of the solar disk.
In the photographs, scientists were able to see only clouds in the planet's atmosphere, which create stripes parallel to the equator. But they moved with great speed, fancifully changing their outlines. Numerous eddies, auroras, and flashes of lightning were recorded in Jupiter's cloud cover. On the planet, the wind speed reaches one hundred kilometers per hour. The most amazing formation in Jupiter's atmosphere is a large red spot 3 times the size of Earth. Astronomers have observed it since the 17th century. It is possible that this is the tip of a gigantic tornado. Jupiter emits more energy than it receives from the Sun. Scientists believe that gases in the center of the planet are compressed to the state of a metallic liquid. This hot core is the power plant that generates winds and a monstrous magnetic field.
But the main surprises for scientists were not presented by Jupiter itself, but by its satellites.
Moons of Jupiter.
There are 16 known satellites of Jupiter. The largest of them Io, Europa, Callisto and Ganymede were discovered by Galileo, they are visible even with strong binoculars. It was believed that the satellites of all planets are similar to the Moon - they are cold and lifeless. But the moons of Jupiter surprised the researchers.
And about - the size of the moon, but this is the first celestial body, except for the Earth, on which active volcanoes were discovered. Io is covered in volcanoes. Its surface is washed by multi-colored lava flows, volcanoes emit sulfur. But what is the reason for the active volcanic activity of such a small cosmic body? Revolving around the huge Jupiter, Io approaches it, then moves away.
Under the influence of either increasing or decreasing gravitational force Io shrinks and expands. Friction forces heated its inner layers to an enormous temperature. Io's volcanic activity is incredible, its surface is changing before our eyes. Io moves in the powerful magnetic field of Jupiter, therefore accumulates a huge electric charge, which is discharged to Jupiter in the form of a continuous stream of lightning, causing storms on the planet.
Europe has a relatively smooth surface with virtually no relief. It is covered with a layer of ice, it is likely that the ocean is hidden under it. Instead of molten rocks, water seeps out of the cracks. This is a completely new kind of geological activity.
Ganymede is the largest satellite in the solar system. Its dimensions are almost the same as those of Mercury.
Callisto dark and cold, its surface pitted by meteorite craters has not changed for billions of years.
Saturn.
Saturn, like Jupiter, does not have a solid surface - it is a gas giant planet. It also consists of hydrogen and helium, but it is colder because it generates less heat itself and receives less of it from the Sun. But on Saturn, the winds are more rapid than on Jupiter. Stripes, vortices and other formations are observed in the atmosphere of Saturn, but they are short-lived and irregular.
Naturally, the attention of scientists was directed to the rings that surround the planet's equator. They were discovered by astronomers back in the 17th century, since then scientists have been trying to understand what they are. The photographs of the rings, transmitted to earth by the robotic space station, surprised the researchers. They managed to identify several hundred nested rings, some intertwined with each other, on the rings they found dark stripes that appeared and disappeared, they were called knitting needles. Scientists were able to see the rings of Saturn with enough close rangebut they had more questions than answers.
In addition to the rings around Saturn, 15 satellites move. The largest of them is Titan, slightly smaller than Mercury. Titan's dense atmosphere is much thicker than Earth's and consists almost entirely of nitrogen, it did not allow us to see the surface of the satellite, but scientists suggest that internal structure Titan is similar to the structure of the Earth. The temperature at its surface is below minus 200 degrees.
Uranus.
Uranus differs from all other planets in that its axis of rotation lies practically in the plane of its orbit, all the planets are like a toy top, and Uranus rotates as if "lying on its side". Voyager managed to "see" little in the atmosphere of Uranus; the planet turned out to be very monotonous in appearance. 5 satellites revolve around Uranus.
Neptune.
Voyager traveled to Neptune for 12 years. How surprised scientists were when on the outskirts of the solar system they saw a planet very similar to Earth. She was rich blue, white clouds were moving in different directions in the atmosphere. Winds blow much stronger on Neptune than on other planets.
There is so little energy on Neptune that the wind, having risen, can no longer stop. Scientists have discovered a system of rings around Neptune, but they are incomplete and represent arcs, there is no explanation for this yet. Neptune and Uranus are also giant planets, but not gas, but ice.
Neptune has 3 moons. One of them - Triton rotates in the opposite direction to the direction of rotation of Neptune itself. Perhaps, it did not form in the gravity zone of Neptune, but was attracted to the planet when it came close to it and fell into its zone of gravity. Triton is the coldest body in the solar system, its surface temperature is slightly above absolute zero (minus 273 degrees). But nitrogen geysers were discovered on Triton, which indicates its geological activity.
Pluto
Now officially Pluto is no longer a planet. Now it should be considered “ dwarf planet", One of three in the Solar System. Pluto's fate was determined in 2006 by a vote of members of the International Astronomical Society in Prague.
To avoid confusion and not to clutter up the maps of the solar system, the International Astronomical Union has prescribed to rank as dwarf planets sufficiently large celestial bodies that are not included in the number of eight previously defined planets. In particular, Pluto, Charon (former satellite of Pluto), the asteroid Ceres orbiting between the orbits of Mars and Jupiter, as well as objects of the so-called Kuiper belt Zena (Xena, object UB313) and Sedna (object 90377) received a new status.
\u003e Solar system
solar system - planets in order, the Sun, structure, system model, satellites, space missions, asteroids, comets, dwarf planets, interesting Facts.
solar system - a place in outer space in which the Sun, planets in order and many other space objects and celestial bodies are located. The solar system is the most precious place we live in, our home.
Our Universe is a huge place where we occupy a tiny corner. But for earthlings, the solar system seems to be the most immense territory, to the far corners of which we are just beginning to approach. And she still hides a ton of mysterious and enigmatic formations. So, despite centuries of research, we have only opened the door to the unknown. So what is the solar system? Today we will look at this issue.
Discovery of the solar system
The actual one needs to look up to the sky and you will see our system. But few peoples and cultures understood exactly where we exist and what place we occupy in space. For a long time we thought that our planet is static, located in the center, and other objects rotate around it.
Still, in ancient times, supporters of heliocentrism appeared, whose ideas would inspire Nicolaus Copernicus to create a true model, where the sun was located in the center.
In the 17th century, Galileo, Kepler and Newton were able to prove that the planet Earth revolves around the star Sun. The discovery of gravity helped to understand that other planets follow the same laws of physics.
The revolutionary moment came with the first telescope from Galileo Galilei. In 1610, he noticed Jupiter and its moons. This will be followed by the discovery of other planets.
In the 19th century, three important observations were made that helped to calculate the true nature of the system and its position in space. In 1839, Friedrich Bessel successfully identified the apparent shift in stellar position. This showed that there is a huge distance between the Sun and the stars.
In 1859, G. Kirchhoff and R. Bunsen used a telescope to carry out spectral analysis of the Sun. It turned out that it consists of the same elements as the Earth. The parallax effect can be seen in the picture below.
As a result, Angelo Secchi was able to match the spectral signature of the Sun with the spectra of other stars. It turned out that they practically converge. Percival Lowell carefully studied the distant corners and orbital paths of the planets. He guessed that there was still an undisclosed object - Planet X. In 1930, in his observatory, Clyde Tombaugh noticed Pluto.
In 1992, scientists pushed the boundaries of the system with the discovery of a trans-Neptunian object, 1992 QB1. From this moment, interest in the Kuiper belt begins. This is followed by the finding of Eris and other objects from the team of Michael Brown. All this will lead to a meeting of the IAU and the removal of Pluto from planetary status. Below you can study in detail the composition of the solar system by looking at all the solar planets in order, the main star the Sun, the asteroid belt between Mars and Jupiter, the Kuiper belt and the Oort Cloud. The solar system also houses the largest planet (Jupiter) and the smallest (Mercury).
The structure and composition of the solar system
Comets are lumps of snow and mud filled with frozen gas, rocks and dust. The closer they come to the Sun, the more they heat up and throw out dust and gas, increasing their brightness.
Dwarf planets rotate around the star, but could not remove foreign objects from orbit. They are inferior in size to standard planets. The most famous representative is Pluto.
The Kuiper Belt is hiding beyond the orbit of Neptune, filled with bodies of ice, and formed into a disk. The most famous representatives are Pluto and Eris. Hundreds of ice dwarfs live on its territory. The farthest is the Oort Cloud. Together they act as a source of arriving comets.
The solar system is only a small part Milky way... Beyond its border is a large-scale space filled with stars. At light speed, it will take 100,000 years to fly over the entire territory. Our galaxy is one of many in the universe.
In the center of the system is the main and only star - the Sun (main sequence G2). First to follow 4 terrestrial planets (inner), an asteroid belt, 4 gas giants, the Kuiper belt (30-50 AU) and a spherical Oort Cloud extending for 100,000 AU. to the interstellar medium.
The sun contains 99.86% of the entire systemic mass, and gravity surpasses all forces. Most of the planets are located near the ecliptic and rotate in a single direction (counterclockwise).
Roughly 99% of the planetary mass is represented by gas giants, with Jupiter and Saturn covering over 90%.
The system is informally divided into several sections. The inner one includes 4 terrestrial planets and an asteroid belt. Next comes the external system with 4 giants. The zone with trans-Neptune objects (TNO) is distinguished separately. That is, you can easily find the outer line, since it is marked by the large planets of the solar system.
Many planets are considered mini-systems, as they have a group of satellites. Gas giants also have rings - small bands of small particles orbiting the planet. Usually large moons arrive in the gravity block. On the lower layout, you can see a comparison of the sizes of the Sun and the planets of the system.
The sun is 98% hydrogen and helium. Terrestrial planets are endowed with silicate rock, nickel and iron. Giants are composed of gases and ices (water, ammonia, hydrogen sulphide and carbon dioxide).
The bodies of the solar system distant from the star have low temperature indicators. From here, the ice giants (Neptune and Uranus) are distinguished, as well as small objects beyond their orbits. Their gases and ices are volatile substances that can condense at a distance of 5 AU. from the sun.
The origin and evolutionary process of the solar system
Our system appeared 4.568 billion years ago as a result of the gravitational collapse of a large-scale molecular cloud, represented by hydrogen, helium and a small amount of heavier elements. This mass collapsed, resulting in a rapid rotation.
Most of the mass gathered in the center. The temperature mark was growing. The nebula shrank, increasing acceleration. This led to flattening into a protoplanetary disk with a red-hot protostar.
Due to the high boiling level near the star, only metals and silicates can exist in solid form. As a result, 4 terrestrial planets appeared: Mercury, Venus, Earth and Mars. There were few metals, so they were unable to increase their size.
But the giants appeared further, where the material was cool and allowed volatile ice compounds to remain solid. There was much more ice, so the planets dramatically increased their scale, attracting huge amounts of hydrogen and helium into the atmosphere. The remnants could not become planets and settled in the Kuiper belt or moved to the Oort Cloud.
For 50 million years of development, the pressure and density of hydrogen in the protostar launched nuclear fusion. Thus the Sun was born. The wind created the heliosphere and threw gas and dust into space.
The system remains in its usual state for now. But the Sun develops and after 5 billion years completely transforms hydrogen into helium. The core will collapse, releasing a huge energy reserve. The star will expand 260 times and become a red giant.
This will lead to the death of Mercury and Venus. Our planet will lose life because it gets hot. As a result, the outer stellar layers will burst into space, leaving behind a white dwarf, the size of our planet. A planetary nebula will form.
Inner solar system
This is the line with the first 4 planets from the star. They all have similar parameters. It is a rocky type represented by silicates and metals. Closer than giants. They are inferior in density and size, and are also devoid of huge lunar families and rings.
Silicates form the crust and mantle, while metals are part of the cores. All, except for Mercury, have an atmospheric layer that allows the formation of weather conditions. Impact craters and tectonic activity are visible on the surface.
Closest to the star is Mercury... It is also the tiniest planet. The magnetic field reaches only 1% of Earth's, and the thin atmosphere causes the planet to be half-hot (430 ° C) and freeze (-187 ° C).
Venus converges in size to the Earth and has a dense atmospheric layer. But the atmosphere is extremely toxic and works as a greenhouse. It consists of 96% carbon dioxide, along with nitrogen and other impurities. Dense clouds are created from sulfuric acid. There are many canyons on the surface, the deepest of which reaches 6400 km.
Land best studied because this is our home. It has a rocky surface, covered with mountains and depressions. In the center is a heavy metal core. The atmosphere contains water vapor, which smoothes the temperature regime. The moon revolves nearby.
because of appearance Mars received the nickname Red Planet. The color is created by oxidation of iron materials on the top layer. Endowed with the largest mountain in the system (Olympus), rising to 21,229 m, as well as the deepest canyon - the Mariner Valley (4000 km). Most of the surface is ancient. There are ice caps at the poles. A thin atmospheric layer hints at water deposits. The core is solid, and there are two satellites near the planet: Phobos and Deimos.
Outer solar system
Gas giants are located here - large-scale planets with lunar families and rings. Despite their size, only Jupiter and Saturn can be seen without telescopes.
The largest planet in the solar system - Jupiter with a rapid rotational speed (10 hours) and an orbital path of 12 years. The dense atmospheric layer is filled with hydrogen and helium. The core can reach Earth size. There are many satellites, weak rings and the Great Red Spot - a powerful storm that has not been able to calm down for the 4th century.
Saturn - the planet, which is recognized by the chic ring system (7 pieces). There are satellites in the system, and the hydrogen and helium atmosphere rotates rapidly (10.7 hours). Spends 29 years to go around the star.
In 1781, William Herschel found Uranus... A day on the giant lasts 17 hours, and the orbital path takes 84 years. Holds a huge amount of water, methane, ammonia, helium and hydrogen. All this is concentrated around the stone core. There is a moon family and rings. In 1986, Voyager 2 flew to him.
Neptune - a distant planet with water, methane, ammonium, hydrogen and helium. There are 6 rings and dozens of satellites. Voyager 2 also flew by in 1989.
Trans-Neptune region of the solar system
Thousands of objects have already been found in the Kuiper belt, but it is believed that up to 100,000 live there with a diameter of more than 100 km. They are extremely small and located at great distances, so the composition is difficult to calculate.
Spectrographs show an ice mixture: hydrocarbons, water ice, and ammonia. Initial analysis showed a wide range of colors from neutral to bright red. This hints at the richness of the composition. Comparison of Pluto and KBO 1993 SC showed that they are extremely different in surface elements.
Water ice was found in 1996 TO66, 38628 Huya and 20,000 Varuna, and crystalline ice was noticed in Kwavara.
The Oort cloud and beyond the solar system
This cloud is believed to extend over 2000-5000 AU. and up to 50,000 AU from the star. The outer edge can be extended by 100,000-200,000 AU. The cloud is divided into two parts: the spherical outer (20000-50000 AU) and the inner (2000-20000 AU).
The outer is home to trillions of bodies with a diameter of a kilometer and more, as well as billions with a width of 20 km. There is no exact information about the mass, but it is believed that Halley's comet is a typical representative. The total mass of the cloud is 3 x 10 25 km (5 lands).
If you focus on comets, then most of the cloud bodies are ethane, water, carbon monoxide, methane, ammonia and hydrogen cyanide. The population is 1-2% asteroids.
Bodies from the Kuiper Belt and Oort Clouds are called trans-Neptunian objects (TNOs), because they are located further than the orbital path of Neptune.
Exploring the Solar System
The size of the solar system still seems immense, but our knowledge has expanded significantly with the sending of probes into outer space. The boom in space exploration began in the middle of the 20th century. Now it can be noted that to all solar planets at least once the terrestrial devices were approaching. We have photos, videos, as well as soil and atmosphere analysis (for some).
The first artificial spacecraft was the Soviet Sputnik-1. He was sent into space in 1957. Spent several months in orbit collecting data on the atmosphere and ionosphere. In 1959, the United States joined with Explorer 6, which took pictures of our planet for the first time.
These devices provided a huge array of information about planetary features. Luna 1 was the first to go to another object. He flew past our satellite in 1959. Mariner became a successful mission to Venus in 1964, Mariner 4 arrived at Mars in 1965, and the 10th flight in 1974 passed Mercury.
Since the 1970s. the attack on the outer planets begins. In 1973, Pioneer 10 flew past Jupiter, and the next mission visited Saturn in 1979. The real breakthrough was the Voyagers, which flew around large giants and their satellites in the 1980s.
The Kuiper Belt is occupied by New Horizons. In 2015, the device successfully reached Pluto, sending the first close pictures and a lot of information. Now he is racing towards distant TNOs.
But we were longing to land on another planet, so rovers and probes began to send in the 1960s. Luna 10 was the first to enter lunar orbit in 1966. In 1971, Mariner 9 landed near Mars, and Verena 9 orbited the second planet in 1975.
Galileo first whirled near Jupiter in 1995, and the famous Cassini appeared near Saturn in 2004. MESSENGER and Dawn visited Mercury and Vesta in 2011. And the latter still managed to fly around the dwarf planet Ceres in 2015.
The first spacecraft to land on the surface was Luna-2 in 1959. Then there were landings on Venus (1966), Mars (1971), asteroid 433 Eros (2001), Titan and Tempel in 2005.
Now controlled vehicles have visited only Mars and the Moon. But the first robotic one was Lunokhod 1 in 1970. Spirit (2004), Opportunity (2004) and Curiosity (2012) landed on Mars.
The 20th century was marked by the space race of America and the USSR. The Soviets had this program Vostok. The first mission took place in 1961, when Yuri Gagarin was in orbit. In 1963, the first woman flew - Valentina Tereshkova.
In the United States, they developed the Mercury project, where they also planned to take people into space. The first American to enter orbit was Alan Shepard in 1961. After the end of both programs, countries focused on long-term and short-term flights.
The main goal was the landing of a man on the moon. The USSR was developing a capsule for 2-3 people, and the Gemini tried to create an apparatus for a safe lunar landing. It ended with Apollo 11 successfully landing Neil Armstrong and Buzz Aldrin on the satellite in 1969. In 1972, 5 more landings were made, and all were American.
The next challenge was to create space station and reusable devices. The Soviets formed the Salyut and Almaz stations. The first station with more crews was NASA's Skylab. The first settlement was Soviet Mir, functioning in 1989-1999. In 2001, it was replaced by the International Space Station.
Columbia was the only reusable spacecraft to complete multiple orbital flights. 5 shuttles completed 121 missions and retired in 2011. Due to accidents, two shuttles crashed: Challenger (1986) and Columbia (2003).
In 2004, George W. Bush announced his intention to return to the Moon and conquer the Red Planet. This idea was supported by Barack Obama. As a result, now all efforts are spent on the exploration of Mars and plans to create a human colony.
All these flights and sacrifices have led to a better understanding of our system, its past and future. IN modern model there are 8 planets, 4 dwarf planets and a huge number of TNOs. Let's not forget about the army of asteroids and planetesimals.
On the page you can find out not only useful information about the solar system, its structure and size, but also get a detailed description and characteristics of all planets in order with names, photos, videos, diagrams and an indication of the distance from the sun. The composition and structure of the solar system will cease to be a mystery. Also use our 3D model to explore all the celestial bodies yourself.
(7
estimates, average: 3,71
out of 5)