Giant planets Jupiter Saturn Uranus Neptune. Planets of the solar system
Temperature difference:
750 degrees Fahrenheit during the day
at night - minus 320 Fahrenheit.
Like the rest of the terrestrial planets: Venus, Earth and Mars, Mercury consists mainly of stone and metal. This peculiar small world is "pitted" with craters, and the planet itself looks like Earth's neighbor - the Moon.
And if you compare with the Earth:
Mass: 5.6% of the earth's mass - diameter: 38% of the earth's.
2) Venus- the second planet farthest from the Sun, the average distance from the Sun is 0.72 AU. e. (108.2 million km), average diameter 12100 km, mass - 4.9 * 10 ^ 24 kg (0.82 Earth masses). The dense atmosphere consists mainly of carbon dioxide, pressure near the surface is about 94 atmospheres, temperature is about 479 Celsius. The surface is mostly flat, composed of basalts; traces of volcanic activity and impact craters have been found. The period of revolution around the Sun is 224.7 days, the period of rotation around its axis is 243 days.
Daytime temperatures reach 895 degrees Fahrenheit (480 degrees Celsius). Due to the dense atmosphere and the unfavorable composition of the gas, the planet is not suitable for human life.
After the Moon, Venus is the most bright object in the earthly sky.
Composition - chambery-desert landscapes predominate. The planet also consists mainly of stone and metal.
And if you compare with the Earth:
- mass: 82% of the earth;
- diameter: 95% of the earth.
Interesting facts: while the rest of the planets of the solar system move in an elliptical orbit (orbit in the form of an ellipse), the orbit of Venus is an almost perfect circle. It is also the only planet in the solar system where a year (225 Earth days) is shorter than a day (241 Earth days). 
3) Land- the third planet from the Sun, the average distance from the Sun is 149.6 million km (1 AU), the average radius is 6371.160 km (equatorial 6378, 160 km, polar 6356.777 km), mass - 6 * 10 ^ 24 kg. The period of revolution around the Sun is 365.3 days, the period of rotation around its axis is 23 h 56 min (sidereal day), the period of rotation relative to the Sun (mean solar day) is 24 h. natural satellite- The moon, which may have arisen in a collision with another cosmic body in antiquity.
The composition of the Earth is dominated by iron (34.6%), oxygen (29.5%), silicon (15.2%), magnesium (12.7%). The density of the Earth's substance, pressure and temperature increase towards its center, or core, where the density is about 12500 kg / m ^ 3, pressure 3.6 * 10 ^ 11 Pa, temperature 5000-6000 Celsius. Under the influence of the Earth's gravitational field, under the conditions of heating of the earth's interior, various chemical composition and physical properties of the geosphere.
According to modern cosmogonic concepts, the Earth was formed about 4.7 billion years ago from gas and dust matter scattered in the protosolar system. The absolute age of the most ancient rocks of the Earth is over 4.5 billion years.
Perhaps the most distinctive feature of the Earth is the presence of water, in which life originated. Another "wealth" of ours is an atmosphere rich in nitrogen and oxygen, without which we would cease to exist altogether.
The earth rotates around its axis at about 1.8 km per hour (if you are at the equator). In addition, the planet is rushing in its orbit around our star - the Sun - at a speed of more than 29 km per second. 
4) Mars- the fourth planet from the Sun, the average distance from the Sun is 1.5 AU. e. (227.9 million km), average diameter 6780 km, mass 6.4 * 10 ^ 23 kg (0.108 Earth masses). The rarefied atmosphere consists mainly of carbon dioxide, the average pressure at the surface is 0.006 atm. The surface of Mars is a dusty-sandy desert with rocky placers, extinct volcanoes, impact craters, branching canyons such as dry riverbeds. The period of revolution around the Sun is 687 days, the period of rotation around its axis is 24 hours 37 minutes. The two known moons of Mars are Phobos and Deimos. Significant scientific material on Mars has been obtained with the help of the Mariner and Mars spacecraft.
I must say, this planet has always excited our imagination, and until scientists proved that there is no intelligent life on Mars, this dusty planet attracted (and still attracts) a lot of attention to itself.
The surface of Mars is more interesting than the surface of most planets. Like Mercury, Venus and Earth, Mars is predominantly rock and metal. The mountains and craters of Mars "scar" its uneven surface. By the way, dusty iron oxides give the planet a specific reddish-brown color (that's why Mars is also called the "Red Planet").
The thin atmosphere and elliptical orbit together contribute to temperatures that range from minus 207 degrees Fahrenheit to a comfortable 80 degrees Fahrenheit in summer (again, if you're at the equator).
Huge storms swirling over Mars have been recently investigated on Mars (similar to the storm in the picture below). These storms are very similar to terrestrial hurricanes.
When studying the planet, one has to answer the following question: is there water on Mars? There is evidence that Mars was at its most comfortable and wettest about 3.7 billion years ago. But the planet gradually cooled, and the water eventually froze. The remnants exist in the form of ice blocks at the poles - these are the so-called polar "caps" of Mars, which partially melt in the summer.
And if you compare with the Earth:
- mass: 11% of the earth;
- diameter: 53% of the earth. 
5) Jupiter- the fifth in a row from the Sun, as well as the largest planet in our solar system, the average distance from the Sun is 5.2 AU. e. (778 million km), equatorial diameter of about 142,800 km, polar - about 134,100 km, mass 1.9 * 10^27 kg (317.8 Earth masses).
It is a gas-liquid body, it does not have a solid surface. Consists mainly of hydrogen and helium. In the upper layers of Jupiter (atmosphere), violent movements and thunderstorm activity are observed. The period of revolution around the Sun is 11.9 years, the period of rotation around its axis is 9 hours 45 minutes (for the polar zone) and 9 hours 50.5 minutes for the equatorial zone. A ring about 6000 km wide and about 1 km thick was found, consisting of particles ranging in size from a few microns to several meters.
Jupiter is so massive that it could pull all the other planets in the solar system towards it. So what can be seen through the high clouds of this giant's thick atmosphere of helium and hydrogen, which interact to give the planet its color?
Jupiter's most famous feature is its swirling cluster of clouds, which are higher than the rest, and are colder than the clouds surrounding them. This vortex is called the Great Red Spot. The Red Spot is like a giant hurricane that causes storm winds to rush at great speed over the rapidly turning planet. Winds blow counterclockwise around this giant vortex formation at speeds up to 250 miles per hour (450 kilometers per hour). By comparison, storms on Earth rarely "accelerate" to speeds in excess of 180 miles per hour. In terms of area, the Red Spot is the size of 2 of our planets !!! Moreover, this whirlwind has been raging for about 300 years. It must be said that the Red Spot is just one of several storm formations on Jupiter.
Inside Jupiter.
In the center of Jupiter there is a stone core, with a mass many times greater than the mass of the Earth. But the main mass of Jupiter is a rather impressive layer of gaseous clouds that cover the core. In this regard, the planet can be compared with a peach, which is soft on top, and inside - with a strong core.
The rapid rotation of Jupiter leads to the deformation of the planet: the diameter of the equator is 7% larger than the polar diameter.
Around Jupiter there are several thin rings and at least 16 satellites. The largest: Ganymede (diameter about 5260 km), Callisto (diameter about 4800 km), Io (about 3600 km), Europe (about 3130 km) - the so-called Galilean satellites of the planet. They consist mainly of "rocky" rocks and water ice.
And if you compare with the Earth:
- mass: 317.8 masses of the Earth;
- diameter: 112 earth diameters. 
6)
Saturn- the next planet of the solar system, the average distance from the Sun is 9.54 AU. e. (1.427 billion km), the average equatorial diameter is about 120500 km, the polar one is about 107500 km, the mass is 5.68*10^26 kg (95.1 Earth masses). The average density of Saturn is less than the density of water (about 0.7 g / cm ^ 3) - the smallest for the planets of the solar system. In structure and chemical composition, it is basically similar to Jupiter. The period of revolution around the Sun is 29.5 years, the period of rotation around its axis is about 10.7 hours (the equatorial regions rotate 5% faster than the polar regions).
The Saturn system also includes the famous rings about 1 km thick.
Like Jupiter, its neighbor, Saturn has a solid core and a gaseous rest. But Saturn is best known for its rings. Kilometer-thick rings consist of countless particles of different sizes: from an inch (about 2.5 cm) to several meters. It is clear that the planet has many more rings than we can see and count. But although we cannot see and count all the rings, however, we are able to distinguish 3 large rings (they are distinguishable in a good telescope).
18 satellites have been discovered, consisting mainly of ice and stone; the largest of them is Titan, with a diameter of about 5200 km. Titan orbits Saturn every 16 days, and we can see it with an amateur telescope at high magnification. Among other things, this satellite is larger than Mercury, has an impressive layer of atmosphere enveloping its surface.
While scientists aren't sure how many "moons" Saturn has, it's roughly 20 or more.
And if you compare with the Earth:
- mass: 95 Earth masses;
- diameter: 9.4 earth diameters. 
7) Uranus is the seventh planet from the sun in the solar system. The average distance from the Sun is 19.18 AU. e. (2871 million km), diameter 50540 km, mass 8.69 * 10 ^ 25 (14.54 Earth masses). In structure and chemical composition, it is basically similar to Jupiter, but contains much more methane and ammonia. The period of revolution around the Sun is 84 years, periodic rotation around its axis is about 17 hours 14 minutes. 15 satellites of Uranus have been discovered (the largest ones are Titania, with a diameter of about 1600 km, and Oberon, with a diameter of about 1550 km) and rings similar in structure to the ring of Jupiter.
Like its neighbors, it mainly consists of gas (surface) and a small stone core.
And if you compare with the Earth:
- mass: 15 earth masses;
- diameter: 4 earth. 
8) Neptune- the penultimate planet of the solar system, the average distance from the Sun is 30.1 AU. e. (4497 million km), the average diameter is about 50,000 km, the mass is 1.02 * 10 ^ 26 kg (17.2 Earth masses). In general, it is similar to Uranus, but differs in violent processes in the atmosphere. The period of revolution around the Sun is 164.8 years, the period of rotation around its axis is 16 hours 6 minutes. It was discovered in 1846 by the German astronomer I. Galle according to the theoretical predictions of the French astronomer W. J. Le Verrier and the English astronomer J. K. Adams.
Composition - a stone core covered with ice, hydrogen, helium, methane. Like other gaseous planets, Neptune has fast hurricane-force winds in its atmosphere, but the planet contains what is believed to be a deep ocean of water.
The planet's rapid rotation powers fierce winds and many storms. There is also an insignificant layer of rings and 8 satellites (the largest is Triton, with a diameter of about 3200 km).
Due to Pluto's strange orbit, Neptune is sometimes the planet farthest from the Sun. Since 1979, Neptune has been the 9th planet from the Sun. On February 11, 1999, it crossed the orbit of Pluto and once again became the 8th planet from the Sun, where it will remain for the next 228 years.
And if you compare with the Earth:
- mass: 17 earth;
- diameter: 4 earth. 
9) Pluto- the last and most distant planet from the Sun in the solar system. The average distance from the Sun is 39.44 AU. e. (5.9 * 10^12 km), diameter about 2300 km, mass 1.2 * 10^22 (0.22 Earth masses). The period of revolution around the Sun is 248.6 years, the period of rotation around its axis is 6.4 days. Pluto has a satellite - Charon, comparable in size to the planet (diameter about km).
Pluto, the size of 2-3 moons (natural satellite of the Earth), is a cold, dark and "frozen" planet. Relatively little is known about her - this planet with a strange orbit.
Pluto's composition is believed to include rock and ice, and has a thin atmosphere composed of nitrogen, methane, and carbon monoxide. Orbit. Pluto's 248-year orbit is such that the planet has to cross the path of Neptune. As already mentioned in the "Neptune" section, from 1979 until the beginning of 1999, Pluto was the 8th planet from the Sun. But now Pluto will remain the 9th planet for the next 228 years.
The orbit of this amazing planet is inclined at an angle of 17 degrees to the orbit of the Earth. It is also interesting that there is evidence that Pluto "left" Neptune. Thus, Pluto can be regarded as a former satellite of Neptune. But there is an opinion that Pluto is a large asteroid and even that the planet is a comet. There is active controversy in this area.
However, it is reliably known that Pluto has one satellite - Sheron, discovered in 1978. A possible hypothesis of its origin is as follows - perhaps it is a fragment of a large cosmic body that collided with Pluto.
And if you compare with the Earth:
- mass: 0.2% of the earth;
- diameter: 18% of the earth.
So, we have completed the characterization of the planets of the solar system. The authors hope that after reading all the information you have a clear idea about the planets around the Sun. 
On March 13, 1781, English astronomer William Herschel discovered the seventh planet in the solar system - Uranus. And on March 13, 1930, American astronomer Clyde Tombaugh discovered the ninth planet in the solar system - Pluto. By the beginning of the 21st century, it was believed that the solar system included nine planets. However, in 2006, the International Astronomical Union decided to strip Pluto of this status.
There are already 60 known natural satellites of Saturn, most of which have been discovered using spacecraft. Most satellites are made up of rocks and ice. The largest satellite, Titan, discovered in 1655 by Christian Huygens, is larger than the planet Mercury. The diameter of Titan is about 5200 km. Titan orbits Saturn every 16 days. Titan is the only satellite to have a very dense atmosphere, 1.5 times the size of Earth's, and consisting mostly of 90% nitrogen, with a moderate amount of methane.
The International Astronomical Union officially recognized Pluto as a planet in May 1930. At that moment, it was assumed that its mass was comparable to the mass of the Earth, but later it was found that the mass of Pluto is almost 500 times less than the Earth's, even less than the mass of the Moon. The mass of Pluto is 1.2 times 1022 kg (0.22 Earth masses). The average distance of Pluto from the Sun is 39.44 AU. (5.9 by 10 to the 12th degree km), the radius is about 1.65 thousand km. The period of revolution around the Sun is 248.6 years, the period of rotation around its axis is 6.4 days. The composition of Pluto supposedly includes rock and ice; the planet has a thin atmosphere composed of nitrogen, methane and carbon monoxide. Pluto has three moons: Charon, Hydra and Nyx.
In the late 20th and early 21st centuries, many objects were discovered in the outer solar system. It has become clear that Pluto is only one of the largest Kuiper belt objects known to date. Moreover, at least one of the objects of the belt - Eris - is a larger body than Pluto and 27% heavier than it. In this regard, the idea arose to no longer consider Pluto as a planet. On August 24, 2006, at the XXVI General Assembly of the International Astronomical Union (IAU), it was decided to henceforth call Pluto not a "planet", but a "dwarf planet".
At the conference, a new definition of the planet was developed, according to which planets are considered to be bodies that revolve around a star (and are not themselves a star), have a hydrostatically balanced shape and have "cleared" the area in the region of their orbit from other, smaller, objects. Dwarf planets will be considered objects that revolve around a star, have a hydrostatically equilibrium shape, but have not "cleared" the nearby space and are not satellites. Planets and dwarf planets are two different class objects of the solar system. All other objects revolving around the Sun and not being satellites will be called small bodies of the solar system.
Thus, since 2006, there have been eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Five dwarf planets are officially recognized by the International Astronomical Union: Ceres, Pluto, Haumea, Makemake, and Eris.
On June 11, 2008, the IAU announced the introduction of the concept of "plutoid". It was decided to call plutoids celestial bodies that revolve around the Sun in an orbit whose radius is greater than the radius of Neptune's orbit, whose mass is sufficient for gravitational forces to give them an almost spherical shape, and which do not clear the space around their orbit (that is, many small objects revolve around them ).
Since it is still difficult to determine the shape and thus the relation to the class of dwarf planets for such distant objects as plutoids, scientists recommended temporarily assigning to plutoids all objects whose absolute asteroid magnitude (brilliance from a distance of one astronomical unit) is brighter than +1. If it later turns out that the object assigned to the plutoids is not a dwarf planet, it will be deprived of this status, although the assigned name will be left. The dwarf planets Pluto and Eris were classified as plutoids. In July 2008, Makemake was included in this category. On September 17, 2008, Haumea was added to the list.
The material was prepared on the basis of information from open sources
The sun holds by its gravity the planets and other bodies belonging to the solar system.
Other bodies are planets and their satellites, dwarf planets and their satellites, asteroids, meteoroids, comets and space dust. But in this article we will only talk about the planets of the solar system. It is they who constitute most masses of objects connected with the Sun by gravity (attraction). There are only eight of them: Mercury, Venus, Earth Mars, Jupiter, Saturn, Uranus and Neptune . The planets are named in order of their distance from the Sun. Until recently, Pluto, the smallest planet, was also among the planets of the solar system, but in 2006 Pluto was deprived of the status of a planet, because. In the outer part of the solar system, many objects more massive than Pluto have been discovered. After the reclassification, Pluto was added to the list of minor planets and received number 134340 in the Minor Planet Center catalog. But some scientists disagree and continue to believe that Pluto should be reclassified back into a planet.
Four planets - Mercury, Venus, Earth and Mars are called terrestrial planets. They are also called inner planets, because their orbits lie inside the Earth's orbit. The terrestrial planets are united by the fact that they are composed of silicates (minerals) and metals.
Four other planets Jupiter, Saturn, Uranus and Neptune - called gas giants, because they are mostly made up of hydrogen and helium and are much more massive than the terrestrial planets. They are also called outer planets.
Look at the image of the terrestrial planets in terms of their size in relation to each other: Earth and Venus are about the same size, and Mercury is the smallest planet among the terrestrial planets (from left to right: Mercury, Venus, Earth, Mars).
The terrestrial planets are united, as we have already said, by their composition, and also by the fact that they have a small number of satellites, that they do not have rings. The three inner planets (Venus, Earth and Mars) have an atmosphere (a shell of gas around a celestial body held by gravity); all have impact craters, rift troughs, and volcanoes.
Consider now each of the terrestrial planets.
Mercury
It is located closest to the Sun and is the smallest planet in the solar system, its mass is 3.3 10 23 kg, which is 0.055 of the mass of the Earth. The radius of Mercury is only 2439.7 ± 1.0 km. The average density of Mercury is quite high - 5.43 g / cm³, which is slightly less than the density of the Earth. Considering that the Earth is larger in size, the value of the density of Mercury indicates an increased content of metals in its bowels.
The planet got its name in honor of the ancient Roman god of trade Mercury: he was swift, and the planet moves across the sky faster than other planets. Mercury has no satellites. Its only known geological features, aside from impact craters, are numerous jagged escarpments extending for hundreds of kilometers. Mercury has an extremely rarefied atmosphere, a relatively large iron core and a thin crust, the origin of which is currently a mystery. Although there is a hypothesis: the outer layers of the planet, consisting of light elements, were torn off as a result of a giant collision, which reduced the size of the planet, and also prevented the complete absorption of Mercury by the young Sun. The hypothesis is very interesting, but requires confirmation.
Mercury revolves around the Sun in 88 Earth days.
Mercury has not yet been sufficiently studied, only in 2009 its complete map was compiled based on images from the Mariner-10 and Messenger spacecraft. No natural satellites have yet been discovered near the planet, and it is not easy to notice it in the sky due to the small angular distance from the Sun.
Venus
It is the second inner planet of the solar system. It revolves around the Sun in 224.7 Earth days. The planet is close in size to the Earth, its mass is 4.8685ˑ10 24 kg, which is 0.815 of the Earth's mass. Like the Earth, it has a thick silicate shell around an iron core and an atmosphere. Venus is the third brightest object in the Earth's sky after the Sun and Moon. It is assumed that internal geological activity occurs inside the planet. The amount of water on Venus is much less than on Earth, and its atmosphere is ninety times denser. Venus has no satellites. It is the hottest planet, its surface temperature exceeds 400 °C. Astronomers believe that the most likely reason for such a high temperature is the greenhouse effect, which occurs due to a dense atmosphere rich in carbon dioxide, which is approximately 96.5%. The atmosphere on Venus was discovered by M. V. Lomonosov in 1761.
No evidence of geological activity has been found on Venus, but since it has no magnetic field, which would prevent the depletion of its essential atmosphere, suggesting that its atmosphere is regularly replenished by volcanic eruptions. Venus is sometimes referred to as " sister of the earth"- they really have a lot in common: they are similar in size, gravity and composition. But there are still more differences. The surface of Venus is covered with thick clouds of highly reflective sulfuric acid, so its surface cannot be seen in visible light. But radio waves were able to penetrate its atmosphere, and with their help, its relief was studied. Disputes of scientists continued for a long time about what is under the thick clouds of Venus. And only in the 20th century, the science of planetology established that the atmosphere of Venus, which consists mainly of carbon dioxide, is explained by the fact that there is no cycle of carbon and life on Venus that could process it into biomass. Scientists believe that once, a very long time ago, there were oceans on Venus similar to those on Earth, but they completely evaporated due to the strong heating of the planet.
Atmospheric pressure on the surface of Venus is 92 times greater than on Earth. Some astronomers believe that volcanic activity on Venus continues even now, but no clear evidence of this has been found. Not found yet... It is believed that Venus is a relatively young planet, by astronomical standards, of course. It is approximately only... 500 million years old.
The temperature on Venus has been calculated to be around +477°C, but scientists believe that Venus is gradually losing its internal heat. Observations from automatic space stations found thunderstorms in the atmosphere of the planet.
The planet got its name in honor of the ancient Roman goddess of love Venus.
Venus has been actively explored with the help of spacecraft. The first spacecraft was the Soviet Venera-1. Then there were the Soviet "Vega", the American "Mariner", "Pioner-Venus-1", "Pioner-Venus-2", "Magellan", the European "Venus Express", the Japanese "Akatsuki". In 1975, the spacecraft Venera-9 and Venera-10 transmitted the first photographs of the surface of Venus to Earth, but the conditions on the surface of Venus are such that none of the spacecraft has worked on the planet for more than two hours. But research on Venus continues.
Land
Our Earth is the largest and densest of the inner planets in the solar system. Among the terrestrial planets, the Earth is unique in connection with its hydrosphere (water shell). Earth's atmosphere differs from the atmospheres of other planets in that it contains free oxygen. The Earth has one natural satellite - the Moon, the only large satellite of the terrestrial planets of the solar system.
But we have a more detailed discussion about the planet Earth in a separate article. Therefore, we will continue the story about the planets of the solar system.
Mars
This planet is smaller than the Earth and Venus, its mass is 0.64185·10 24 kg, which is 10.7% of the mass of the Earth. Mars is also called red planet"- due to iron oxide on its surface. Its rarefied atmosphere consists mainly of carbon dioxide (95.32%, the rest is nitrogen, argon, oxygen, carbon monoxide, water vapor, nitric oxide), and the pressure on the surface is 160 times less than that of the earth. Impact craters like those on the moon, as well as volcanoes, valleys, deserts and polar ice caps like those on Earth, all make it possible to classify Mars as a terrestrial planet.
The planet got its name in honor of Mars - the ancient Roman god of war (which corresponds to the ancient Greek Ares). Mars has two natural, relatively small satellites - Phobos and Deimos (translated from ancient Greek - "fear" and "horror" - that was the name of the two sons of Ares, who accompanied him in battle).
Mars was studied by the USSR, the USA and the European Space Agency (ESA). The USSR / Russia, the USA, ESA and Japan sent the Automatic Interplanetary Station (AMS) to Mars to study it, there were several programs to study this planet: Mars, Phobos, Mariner, Viking, Mars Global Surveyor other.
It has been established that due to low pressure, water cannot exist in a liquid state on the surface of Mars, but scientists suggest that conditions on the planet were different in the past, so they do not exclude the presence of primitive life on the planet. In 2008, water in the state of ice was discovered on Mars by NASA's Phoenix spacecraft. The surface of Mars is explored by rovers. The geological data they have collected suggests that earlier, most of the surface of Mars was covered with water. On Mars, they even found something like geysers - sources of hot water and steam.
Mars can be seen from Earth with the naked eye.
The minimum distance from Mars to the Earth is 55.76 million km (when the Earth is exactly between the Sun and Mars), the maximum is about 401 million km (when the Sun is exactly between the Earth and Mars).
The average temperature on Mars is -50 °C. The climate, like on Earth, is seasonal.
asteroid belt
Between Mars and Jupiter is a belt of asteroids - small bodies of the solar system. Scientists suggest that these are the remnants of the formation of the solar system, which could not unite into a large body due to the gravitational perturbations of Jupiter. Asteroids vary in size from a few meters to hundreds of kilometers.
outer solar system
The outer solar system contains gas giants ( Jupiter, Saturn, Uranus and Neptune ) and their companions. The orbits of many short-period comets are also located here. Due to their greater distance from the Sun, and therefore much lower temperature, the solid objects of this region contain ices of water, ammonia, and methane. In the photo you can compare their sizes (from left to right: Jupiter, Saturn, Uranus, Neptune).
Jupiter
This is a huge planet with a mass of 318 Earth masses, which is 2.5 times more massive than all the other planets combined, and the equatorial radius is 71,492 ± 4 km. It consists mainly of hydrogen and helium. Jupiter is the most powerful (after the Sun) radio source in the solar system. The average distance between Jupiter and the Sun is 778.57 million km. The presence of life on Jupiter seems unlikely due to the low concentration of water in the atmosphere, the absence of a solid surface, etc. Although scientists do not exclude the possibility of the existence of water-hydrocarbon life on Jupiter in the form of some undefined organisms.
Jupiter has been known to people since ancient times, which is reflected in mythology different countries, and its name comes from the ancient Roman thunder god Jupiter.
There are 67 known moons of Jupiter, the largest of which were discovered by Galileo Galilei in 1610.
Jupiter is explored with ground and orbital telescopes; Since the 1970s, 8 NASA interplanetary vehicles have been sent to the planet: Pioneers, Voyagers, Galileo and others. On the planet, powerful storms, lightning, auroras, many times superior to those on earth, have been noticed.
Saturn
A planet known for its ring system. In fact, these romantic rings are just flat concentric formations of ice and dust that lie in the equatorial plane of Saturn. Saturn has a structure of the atmosphere and magnetosphere somewhat similar to Jupiter, but much smaller: 60% of Jupiter's mass (5.6846 10 26 kg). Equatorial radius - 60 268 ± 4 km.
The name of the planet was in honor of the Roman god of agriculture, Saturn, so its symbol is a sickle.
The main component of Saturn is hydrogen with helium impurities and traces of water, methane, ammonia and heavy elements.
Saturn has 62 moons. Of these, the largest is Titan. It is interesting in that it is larger than the planet Mercury and has the only dense atmosphere among the satellites of the solar system.
Observations of Saturn have been going on for a long time: even Galileo Galilei noticed in 1610 that Saturn has “two companions” (satellites). And Huygens in 1659, using a more powerful telescope, saw the rings of Saturn and discovered its largest satellite, Titan. Then, gradually, astronomers discovered other satellites of the planet.
The modern study of Saturn began in 1979, when the Pioneer 11 automatic interplanetary station of the United States flew near Saturn, and then finally approached it. Then the American spacecraft Voyager 1 and Voyager 2 followed to Saturn, as well as Cassini-Huygens, which after 7 years of flight on July 1, 2004 reached the Saturn system and went into orbit around the planet. The main tasks were to study the structure and dynamics of the rings and satellites, as well as to study the dynamics of the atmosphere and magnetosphere of Saturn and a detailed study of the planet's largest satellite, Titan. In 2009, a joint American-European project between NASA and ESA appeared to launch the AMS Titan Saturn System Mission to study Saturn and its moons Titan and Enceladus. During it, the station will fly to the Saturn system for 7-8 years, and then become a satellite of Titan for two years. It will also launch a probe balloon into Titan's atmosphere and a lander.
The lightest of the outer planets is 14 Earth masses (8.6832 10 25 kg). Uranus was discovered in 1781 by the English astronomer William Herschel using a telescope and named after the Greek sky god Uranus. It turns out that Uranus is distinguishable in the sky with the naked eye, but those who saw it before did not guess that it was a planet, because. the light from it was very dim, and the movement was very slow.
Uranus, as well as Neptune similar to it, are classified into the category " ice giants”, as there are many modifications of ice in their bowels.
The atmosphere of Uranus is mostly hydrogen and helium, but there are also traces of methane, solid ammonia. Its atmosphere is the coldest (−224 °C).
Uranus also has a ring system, a magnetosphere and 27 moons. The axis of rotation of Uranus lies, as it were, “on its side” relative to the plane of revolution of this planet around the Sun. As a result, the planet is turned to the Sun alternately with the north pole, then the south, then the equator, then the middle latitudes.
In 1986 the American spacecraft Voyager 2 transmitted close-up images of Uranus to Earth. The images do not show images of such storms as on Jupiter, but according to observations from Earth, seasonal changes are taking place there, weather activity has been noticed.
Neptune
Neptune is smaller than Uranus (equatorial radius 24 764 ± 15 km), but its mass is 1.0243 10 26 kg more than the mass of Uranus and is 17 Earth masses.
It is the most distant planet in the solar system. Its name is associated with the name of Neptune - the Roman god of the seas, so the trident of Neptune is an astronomical symbol.
Neptune is the first planet discovered by mathematical calculations, not observations (Neptune is not visible to the naked eye), and this happened in 1846. This was done by a French mathematician who studied celestial mechanics, who worked most of his life at the Paris Observatory - Urbain Jean Joseph Le Verrier.
Although Galileo Galilei observed Neptune in 1612 and 1613, he mistook the planet for fixed star in conjunction with Jupiter in the night sky. Therefore, the discovery of Neptune is not attributed to Galileo.
Soon, its satellite Triton was also discovered, but the remaining 12 satellites of the planet were discovered in the 20th century.
Neptune, like Saturn and Pluto, has a ring system.
Neptune's atmosphere, like that of Jupiter and Saturn, is mostly hydrogen and helium, with traces of hydrocarbons and possibly nitrogen, but contains a lot of ice. The core of Neptune, like Uranus, consists mainly of ice and rocks. The planet seems of blue color- this is due to traces of methane in outer layers atmosphere.
In the atmosphere of Neptune, the strongest winds among the planets of the solar system rage.
Neptune was visited by only one spacecraft, Voyager 2, which flew close to the planet on August 25, 1989.
This planet, like all the others, holds many mysteries. For example, for unknown reasons, the planet's thermosphere has an abnormally high temperature. But it is too far from the Sun for it to heat up the thermosphere with ultraviolet radiation. Here's a challenge for you, future astronomers. And the Universe sets a lot of such tasks, enough for everyone ...
The weather on Neptune is characterized by strong storms, winds reaching almost supersonic speeds (about 600 m/s).
Other bodies of the solar system
This comets- small bodies of the solar system, usually only a few kilometers in size, consisting mainly of volatile substances(ice), centaurs- ice comet-like objects, trans-Neptunian objects located in space beyond Neptune, Kuiper belt- fragments similar to the asteroid belt, but consisting mainly of ice, scattered disk…
To the question of where exactly the solar system ends and interstellar space begins, there is no exact answer yet ...
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. For a long time, astronomers studied the 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 size of the planets and their distances from the Sun, formed their own idea of the structure of the planets, even suggested that Venus and Mars could be similar to Earth, and there may be life on them.
The launch of automatic space stations to the planets made it possible to significantly expand, and in many respects to revise, ideas about the planets: it became possible to see photographs of the surface, to explore the soil and atmosphere of the planets.
Mercury.
Mercury is a small planet, slightly larger than the Moon. Its surface is also littered with meteorite impact craters. No geological processes have erased these dents from his face. Inside Mercury is cold. Around the Sun, it moves faster than other planets, and around its axis very slowly. Having circled the Sun twice, Mercury only has time to turn around its axis three times. Because of this, the temperature on the sunny side of the planet exceeds 300 degrees, and on the unlit side, darkness and severe cold reign. Mercury has almost no atmosphere.
Venus.
Exploring Venus is not easy. It is enveloped in a thick layer of clouds, and under this serene exterior hides a real hell, the pressure exceeds the earth's by a hundred times, the temperature on the surface is about 500 degrees, which is caused by the "greenhouse effect". The Soviet automatic station "Venera - 9" for the first time managed to transmit to Earth images of a surface filled with lava and covered with stones. Under the conditions of Venus, the apparatus lowered to the surface of the planet quickly fails, so American scientists decided to obtain data on the relief of the planet in a different way.
The automatic station "Magellan", flying around Venus many times, probed the planet with a radar, as a result, a comprehensive picture of the surface was obtained. In some places, the relief of Venus is similar to 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 cakes with steep edges and a flat crown. The surface of the planet is carved with channels that have been carved by lava. Traces of active volcanic activity are visible everywhere. Meteor craters on the surface of Venus are distributed evenly, which means that its surface took shape at the same time. Scientists cannot explain how this could happen, 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 the earth's, it mainly consists of carbon dioxide. The thickness of the gaseous shell of Venus, in comparison with the earth, is monstrously large. The layer of clouds reaches 20 km. They found the presence of concentrated aqueous solution sulfuric acid. Sunlight does not reach the surface of Venus, twilight reigns there, it is raining sulfur, the landscape is constantly illuminated by flashes of lightning. High in the atmosphere of the planet, constant winds rage that drive clouds at great speed, the upper layer of the Venusian atmosphere makes a complete revolution around the planet within four Earth days. Solid Venus, on the contrary, rotates around its axis very slowly and in a different direction than all the 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 automatic spacecraft began to be 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 topography. Researchers have discovered 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 grew 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.
Among the Martian landscapes, reddish rocky deserts predominate. Light transparent clouds float above them in the pink sky. blue skies becomes sunset. The atmosphere of Mars is very rarefied. 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 plane of the orbit 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, even in a summer day, does not exceed 0 degrees, 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.
From Earth, Mars is seen as a reddish star, which is probably why it bears the name of the god of war, Mars. Two of his satellites were named Phobos and Deimos, which in ancient Greek means "fear" and "horror". The satellites of Mars are space "rocks" of irregular shape. Phobos is 18km x 22km and Deimos is 10km x 16km.
The planets are giants.
In 1977, American scientists and engineers launched an automatic interplanetary station towards Jupiter as part of the Voyager program. Once every 175 years, Jupiter, Saturn, Neptune and Pluto are located in such a way relative to the Earth that a launched spacecraft can examine all these planets in one flight. The scientists calculated that certain conditions the spacecraft, flying up to the planet, falls into the gravitational sling, the planet itself sends the apparatus further to another planet. The calculations turned out to be correct. Earthlings were able to see these distant planets and their satellites through the "eyes" of space robots, unique information was transmitted to Earth.
Jupiter.
Jupiter is the most big planet in the solar system. It has no 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 the 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, whimsically changing their outlines. Numerous whirlwinds, auroras and flashes of lightning have been recorded in Jupiter's cloud cover. On the planet, the wind speed reaches one hundred kilometers per hour. The most amazing formation in the atmosphere of Jupiter is a large red spot 3 times the size of the Earth. Astronomers have been observing it since the 17th century. It is possible that this is the tip of a gigantic tornado. Jupiter releases more energy than it receives from the Sun. Scientists believe that in the center of the planet, gases 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 presented not by Jupiter itself, but by its satellites.
Satellites of Jupiter.
There are 16 known moons 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 like the moon - they are cold and lifeless. But Jupiter's moons surprised researchers.
And about- the size of the moon, but this is the first heavenly body, except for the Earth, on which active volcanoes have been 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? Rotating around the huge Jupiter, Io either approaches it or moves away.
Under the influence of either increasing or decreasing gravitational force, Io either contracts or 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 Jupiter's powerful magnetic field, so it builds up a huge electrical charge that discharges onto Jupiter in a continuous stream of lightning, causing storms on the planet.
Europe has a relatively smooth surface, virtually without relief. It is covered with a layer of ice, it is likely that the ocean is hiding under it. Instead of molten rocks, water oozes from cracks here. It's perfect the new kind 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 with 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, since it produces less heat itself and receives less from the Sun. But on Saturn the winds are faster 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 in the 17th century, since then scientists have been trying to understand what they are. Photos of the rings, transmitted to earth by an automatic space station, surprised the researchers. They managed to identify several hundred nested rings, some intertwined with each other, dark stripes were found on the rings that appeared and disappeared, they were called knitting needles. Scientists were able to see the rings of Saturn from a fairly close distance, but they had more questions than answers.
In addition to the rings, 15 satellites move around Saturn. The largest of them - Titan is slightly smaller than Mercury. The dense atmosphere of Titan is much thicker than Earth's and almost entirely composed of nitrogen, it did not allow to see the surface of the satellite, but scientists suggest that the internal structure of 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 almost in the plane of its orbit, all the planets look 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 outwardly turned out to be very monotonous. There are 5 satellites around Uranus.
Neptune.
It took Voyager 12 years to reach Neptune. How surprised were the scientists when on the outskirts solar system saw a planet very similar to Earth. It was deep blue in color, white clouds were moving in different directions in the atmosphere. Winds on Neptune blow much stronger 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 are arcs, there is no explanation for this yet. Neptune and Uranus are also giant planets, but not gas ones, but ice ones.
Neptune has 3 satellites. One of them - Triton rotates in the opposite direction to the rotation of Neptune itself. Perhaps it did not form in Neptune's gravity zone, but was attracted to the planet when it came close to it and fell into its zone of attraction. Triton is the coldest body in the solar system, its surface temperature is slightly higher absolute zero(minus 273 degrees). But nitrogen geysers have been discovered on Triton, which indicates its geological activity.
Pluto
Pluto is now officially no longer a planet. Now it should be considered a "dwarf planet", one of three in the solar system. The fate of Pluto was determined in 2006 by a vote of members of the International Astronomical Society in Prague.
To avoid confusion and not clutter up the maps of the solar system, the International Astronomical Union has ordered to rank as dwarf planets rather large celestial bodies that are not among the eight previously identified planets. In particular, Pluto, Charon (a former satellite of Pluto), the asteroid Ceres circulating between the orbits of Mars and Jupiter, as well as the objects of the so-called Kuiper belt Zena (Xena, object UB313) and Sedna (object 90377) received a new status.
Space has attracted people's attention for a long time. Astronomers began to study the planets of the solar system in the Middle Ages, looking at them through primitive telescopes. But a thorough classification, description of the features of the structure and movement of celestial bodies became possible only in the 20th century. With the advent of powerful equipment, state-of-the-art observatories and spaceships several previously unknown objects were discovered. Now each student can list all the planets of the solar system in order. Almost all of them have been landed by a space probe, and so far man has only been to the Moon.
What is the solar system
The universe is huge and includes many galaxies. Our solar system is part of a galaxy with over 100 billion stars. But there are very few that look like the Sun. Basically, they are all red dwarfs, which are smaller in size and do not shine as brightly. Scientists have suggested that the solar system was formed after the emergence of the sun. Its huge field of attraction captured a gas-dust cloud, from which, as a result of gradual cooling, particles of solid matter were formed. Over time, celestial bodies formed from them. It is believed that the Sun is now in the middle of its life path, therefore, it will exist, as well as all celestial bodies dependent on it, for several billion more years. Near space has been studied by astronomers for a long time, and any person knows what planets of the solar system exist. Photos of them, taken from space satellites, can be found on the pages of various information resources dedicated to this topic. All celestial bodies are held by the Sun's strong gravitational field, which makes up over 99% of the solar system's volume. Large celestial bodies revolve around the star and around their axis in one direction and in one plane, which is called the plane of the ecliptic.
Solar system planets in order
In modern astronomy, it is customary to consider celestial bodies, starting from the Sun. In the 20th century, a classification was created, which includes 9 planets of the solar system. But recent space exploration and latest discoveries prompted scientists to revise many positions in astronomy. And in 2006, at the international congress, due to its small size (a dwarf, not exceeding three thousand km in diameter), Pluto was excluded from the number of classical planets, and eight of them remained. Now the structure of our solar system has taken on a symmetrical, slender appearance. It includes four terrestrial planets: Mercury, Venus, Earth and Mars, then comes the asteroid belt, followed by four giant planets: Jupiter, Saturn, Uranus and Neptune. On the outskirts of the solar system also passes which scientists called the Kuiper belt. This is where Pluto is located. These places are still little studied because of their remoteness from the Sun.
Features of the terrestrial planets
What makes it possible to attribute these celestial bodies to one group? We list the main characteristics of the inner planets:
- relatively small size;
- hard surface, high density and similar composition (oxygen, silicon, aluminum, iron, magnesium and other heavy elements);
- the presence of an atmosphere;
- the same structure: a core of iron with nickel impurities, a mantle consisting of silicates, and a crust of silicate rocks (except for Mercury - it has no crust);
- a small number of satellites - only 3 for four planets;
- rather weak magnetic field.
Features of the giant planets
As for the outer planets, or gas giants, they have the following similar characteristics:
- large size and weight;
- they do not have a solid surface and are composed of gases, mainly helium and hydrogen (which is why they are also called gas giants);
- a liquid core consisting of metallic hydrogen;
- high rotation speed;
- a strong magnetic field, which explains the unusual nature of many processes occurring on them;
- there are 98 satellites in this group, most of which belong to Jupiter;
- the most salient feature gas giants is the presence of rings. All four planets have them, although they are not always noticeable.
The first planet is Mercury
It is located closest to the Sun. Therefore, from its surface, the luminary looks three times larger than from the Earth. This also explains the strong temperature fluctuations: from -180 to +430 degrees. Mercury is moving very fast in its orbit. Maybe that's why he got such a name, because in Greek mythology, Mercury is the messenger of the gods. There is almost no atmosphere here, and the sky is always black, but the Sun shines very brightly. However, there are places at the poles where its rays never hit. This phenomenon can be explained by the tilt of the axis of rotation. No water was found on the surface. This circumstance, as well as the anomalously high daytime temperature (as well as the low nighttime temperature) fully explain the fact that there is no life on the planet.
Venus
If we study the planets of the solar system in order, then the second one is Venus. People could observe her in the sky in ancient times, but since she was shown only in the morning and in the evening, it was believed that these were 2 different objects. By the way, our Slavic ancestors called her Flicker. It is the third brightest object in our solar system. Formerly people they called it the morning and evening star, because it is best seen before sunrise and sunset. Venus and Earth are very similar in structure, composition, size and gravity. Around its axis, this planet moves very slowly, making a complete revolution in 243.02 Earth days. Of course, the conditions on Venus are very different from those on Earth. It is twice as close to the Sun, so it is very hot there. The high temperature is also explained by the fact that thick clouds of sulfuric acid and an atmosphere of carbon dioxide create a greenhouse effect on the planet. In addition, the pressure at the surface is 95 times greater than on Earth. Therefore, the first ship that visited Venus in the 70s of the 20th century survived there for no more than an hour. A feature of the planet is also the fact that it rotates in the opposite direction, compared to most planets. Astronomers know nothing more about this celestial object yet.
Third planet from the Sun
The only place in the solar system, and indeed in the entire universe known to astronomers, where life exists, is the Earth. In the terrestrial group, it has the largest dimensions. What else is her
- The largest gravity among the terrestrial planets.
- Very strong magnetic field.
- High density.
- It is the only one among all the planets that has a hydrosphere, which contributed to the formation of life.
- It has the largest, in comparison with its size, satellite, which stabilizes its tilt relative to the Sun and affects natural processes.
The planet Mars
It is one of the smallest planets in our Galaxy. If we consider the planets of the solar system in order, then Mars is the fourth from the Sun. Its atmosphere is very rarefied, and the pressure on the surface is almost 200 times less than on Earth. For the same reason, very strong temperature drops are observed. The planet Mars is little studied, although it has long attracted the attention of people. According to scientists, this is the only celestial body on which life could exist. After all, in the past there was water on the surface of the planet. Such a conclusion can be drawn from the fact that there are large ice caps at the poles, and the surface is covered with many furrows, which could be dried up river beds. In addition, there are some minerals on Mars that can only be formed in the presence of water. Another feature of the fourth planet is the presence of two satellites. Their unusualness is that Phobos gradually slows down its rotation and approaches the planet, while Deimos, on the contrary, moves away.
What is Jupiter famous for?
The fifth planet is the largest. 1300 Earths would fit in the volume of Jupiter, and its mass is 317 times more than the earth. Like all gas giants, its structure is hydrogen-helium, reminiscent of the composition of stars. Jupiter is the most interesting planet that has many characteristic features:
- it is the third brightest celestial body after the Moon and Venus;
- Jupiter has the strongest magnetic field of all the planets;
- it completes a full rotation around its axis in just 10 earth hours - faster than other planets;
- an interesting feature of Jupiter is a large red spot - this is how an atmospheric vortex is visible from the Earth, rotating counterclockwise;
- like all giant planets, it has rings, though not as bright as those of Saturn;
- this planet has the largest number of satellites. He has 63 of them. The most famous are Europa, where they found water, Ganymede - the largest satellite of the planet Jupiter, as well as Io and Calisto;
- another feature of the planet is that in the shade the surface temperature is higher than in places illuminated by the Sun.
Planet Saturn
This is the second largest gas giant, also named after the ancient god. It consists of hydrogen and helium, but traces of methane, ammonia and water have been found on its surface. Scientists have found that Saturn is the most rarefied planet. Its density is less than that of water. This gas giant rotates very quickly - it completes one revolution in 10 Earth hours, as a result of which the planet is flattened from the sides. Huge speeds on Saturn and near the wind - up to 2000 kilometers per hour. It's more than the speed of sound. Saturn has another distinguishing feature- he keeps 60 satellites in his field of attraction. The largest of them - Titan - is the second largest in the entire solar system. The uniqueness of this object lies in the fact that, exploring its surface, scientists first discovered a celestial body with conditions similar to those that existed on Earth about 4 billion years ago. But the most main feature Saturn is the presence of bright rings. They encircle the planet around the equator and reflect more light than herself. Four is the most amazing phenomenon in the solar system. Unusually, the inner rings move faster than the outer ones.
- Uranus
So, we continue to consider the planets of the solar system in order. The seventh planet from the Sun is Uranus. It is the coldest of all - the temperature drops to -224 ° C. In addition, scientists did not find metallic hydrogen in its composition, but found modified ice. Because Uranus is classified as a separate category of ice giants. An amazing feature of this celestial body is that it rotates while lying on its side. The change of seasons on the planet is also unusual: winter reigns there for 42 Earth years, and the Sun does not appear at all, summer also lasts 42 years, and the Sun does not set at this time. In spring and autumn, the luminary appears every 9 hours. Like all giant planets, Uranus has rings and many satellites. As many as 13 rings revolve around it, but they are not as bright as those of Saturn, and the planet holds only 27 satellites. If we compare Uranus with the Earth, then it is 4 times larger than it, 14 times heavier and is located at a distance from the Sun, in 19 times greater than the path to the luminary from our planet.
Neptune: the invisible planet
After Pluto was excluded from the number of planets, Neptune became the last from the Sun in the system. It is located 30 times farther from the star than the Earth, and is not visible from our planet even through a telescope. Scientists discovered it, so to speak, by accident: observing the peculiarities of the movement of the planets closest to it and their satellites, they concluded that there must be another large celestial body beyond the orbit of Uranus. After discovery and research, it turned out interesting features this planet:
- due to the presence of a large amount of methane in the atmosphere, the color of the planet from space appears blue-green;
- Neptune's orbit is almost perfectly circular;
- the planet rotates very slowly - it completes one circle in 165 years;
- Neptune is 4 times larger than the Earth and 17 times heavier, but the force of attraction is almost the same as on our planet;
- the largest of the 13 moons of this giant is Triton. It is always turned to the planet on one side and slowly approaches it. Based on these signs, scientists have suggested that it was captured by Neptune's gravity.
All over the galaxy Milky Way- about a hundred billion planets. So far, scientists cannot even study some of them. But the number of planets in the solar system is known to almost all people on Earth. True, in the 21st century, interest in astronomy has faded a little, but even children know the name of the planets of the solar system.
