Construction of the solar system. Comparative characteristics of the planets of the solar system: description and interesting facts

What is the solar system in which we live? The answer will be as follows: this is our central star, the Sun and all the cosmic bodies that revolve around it. These are large and small planets, as well as their satellites, comets, asteroids, gases and cosmic dust.

The name of the solar system was given by the name of its star. In a broad sense, "solar" is often understood as any star system.

How did the solar system originate?

According to scientists, the solar system was formed from a giant interstellar cloud of dust and gases due to gravitational collapse in a separate part of it. As a result, a protostar formed in the center, then turned into a star - the Sun, and a huge protoplanetary disk, from which all the components of the solar system listed above were subsequently formed. The process is believed to have begun about 4.6 billion years ago. This hypothesis has been called the nebular one. Thanks to Emmanuel Swedenborg, Immanuel Kant and Pierre-Simon Laplace, who proposed it back in the 18th century, it eventually became generally accepted, but over the course of many decades it was refined, new data were introduced into it, taking into account the knowledge of modern sciences. So, it is assumed that due to the increase and intensification of collisions of particles with each other, the temperature of the object grew, and after it reached a value of several thousand kelvins, the protostar acquired a glow. When the temperature indicator reached millions of kelvins, a thermonuclear fusion reaction began in the center of the future Sun - the conversion of hydrogen into helium. It turned into a star.

The sun and its features

Our luminary scientists refer to the type of yellow dwarfs (G2V) according to the spectral classification. This is the closest star to us, its light reaches the surface of the planet in just 8.31 seconds. From Earth, the radiation appears to have a yellow tint, although in reality it is almost white.

The main components of our luminary are helium and hydrogen. In addition, thanks to spectral analysis, it was found that the Sun contains iron, neon, chromium, calcium, carbon, magnesium, sulfur, silicon, and nitrogen. Thanks to the thermonuclear reaction continuously going on in its depths, all life on Earth receives the necessary energy. Sunlight is an integral part of photosynthesis, which produces oxygen. Without sunlight, it would be impossible, therefore, an atmosphere suitable for a protein life form could not form.

Mercury

This is the closest planet to our sun. Together with the Earth, Venus and Mars, it belongs to the planets of the so-called terrestrial group. Mercury got its name because of the high speed of movement, which, according to myths, distinguished the fleet-footed ancient god. The Mercury year is 88 days.

The planet is small, its radius is only 2439.7, and it is smaller in size than some of the large satellites of the giant planets, Ganymede and Titan. However, unlike them, Mercury is quite heavy (3.3 10 23 kg), and its density is only slightly behind the earth's. This is due to the presence of a heavy dense core of iron in the planet.

There is no change of seasons on the planet. Its desert surface resembles that of the Moon. It is also covered with craters, but even less habitable. So, on the day side of Mercury the temperature reaches +510 °C, and on the night side -210 °C. These are the sharpest drops in the entire solar system. The planet's atmosphere is very thin and rarefied.

Venus

This planet, named after the ancient Greek goddess of love, is more similar to the Earth than others in the solar system in terms of its physical parameters - mass, density, size, volume. For a long time they were considered twin planets, but over time it turned out that their differences are huge. So, Venus has no satellites at all. Its atmosphere consists of almost 98% carbon dioxide, and the pressure on the planet's surface exceeds the earth's by 92 times! Clouds above the surface of the planet, consisting of sulfuric acid vapor, never dissipate, and the temperature here reaches +434 °C. Acid rains are falling on the planet, thunderstorms are raging. There is high volcanic activity here. Life, in our understanding, cannot exist on Venus; moreover, descent spacecraft cannot withstand such an atmosphere for a long time.

This planet is clearly visible in the night sky. This is the third brightest object for an earthly observer, it shines with white light and surpasses all stars in brightness. The distance to the Sun is 108 million km. It completes a revolution around the Sun in 224 Earth days, and around its own axis - in 243.

Earth and Mars

These are the last planets of the so-called terrestrial group, the representatives of which are characterized by the presence of a solid surface. In their structure, the core, mantle and crust are distinguished (only Mercury does not have it).

Mars has a mass equal to 10% of the mass of the Earth, which, in turn, is 5.9726 10 24 kg. Its diameter is 6780 km, almost half that of our planet. Mars is the seventh largest planet in the solar system. Unlike Earth, which has 71% of its surface covered by oceans, Mars is completely dry land. Water has been preserved under the surface of the planet in the form of a massive ice sheet. Its surface has a reddish hue due to the high content of iron oxide in the form of maghemite.

The atmosphere of Mars is very rarefied, and the pressure on the surface of the planet is 160 times less than we are used to. On the surface of the planet there are impact craters, volcanoes, depressions, deserts and valleys, and at the poles there are ice caps, just like on Earth.

The Martian day is slightly longer than the Earth day, and the year is 668.6 days. Unlike the Earth, which has one moon, the planet has two irregular satellites - Phobos and Deimos. Both of them, like the Moon to the Earth, are constantly turned to Mars by the same side. Phobos is gradually approaching the surface of its planet, moving in a spiral, and is likely to eventually fall on it or fall apart. Deimos, on the other hand, is gradually moving away from Mars and may leave its orbit in the distant future.

Between the orbits of Mars and the next planet, Jupiter, there is an asteroid belt consisting of small celestial bodies.

Jupiter and Saturn

What planet is the largest? There are four gas giants in the solar system: Jupiter, Saturn, Uranus and Neptune. Jupiter is the largest of them. Its atmosphere, like that of the Sun, is predominantly hydrogen. The fifth planet, named after the god of thunder, has an average radius of 69,911 km and a mass exceeding that of the earth by 318 times. The planet's magnetic field is 12 times stronger than Earth's. Its surface is hidden under opaque clouds. So far, scientists find it difficult to say exactly what processes can occur under this dense veil. It is assumed that on the surface of Jupiter there is a boiling hydrogen ocean. Astronomers consider this planet a "failed star" due to some similarity in their parameters.

Jupiter has 39 satellites, 4 of which - Io, Europa, Ganymede and Callisto - were discovered by Galileo.

Saturn is somewhat smaller than Jupiter, it is the second largest among the planets. This is the sixth, next planet, also consisting of hydrogen with helium impurities, a small amount of ammonia, methane, water. Hurricanes rage here, the speed of which can reach 1800 km / h! Saturn's magnetic field is not as strong as Jupiter's, but stronger than Earth's. Both Jupiter and Saturn are somewhat flattened at the poles due to rotation. Saturn is 95 times heavier than earth, but its density is less than that of water. It is the least dense celestial body in our system.

A year on Saturn lasts 29.4 Earth days, a day is 10 hours 42 minutes. (Jupiter has a year - 11.86 Earth, a day - 9 hours 56 minutes). It has a system of rings consisting of solid particles of various sizes. Presumably, these may be the remains of the collapsed satellite of the planet. In total, Saturn has 62 satellites.

Uranus and Neptune are the last planets

The seventh planet of the solar system is Uranus. It is 2.9 billion km away from the Sun. Uranus is the third largest among the planets of the solar system (average radius - 25,362 km) and the fourth largest (exceeds the earth by 14.6 times). A year here lasts 84 Earth hours, a day - 17.5 hours. In the atmosphere of this planet, in addition to hydrogen and helium, a significant volume is occupied by methane. Therefore, for an earthly observer, Uranus has a pale blue color.

Uranus is the coldest planet in the solar system. The temperature of its atmosphere is unique: -224 °C. Why Uranus has a lower temperature than planets farther from the Sun is unknown to scientists.

This planet has 27 moons. Uranus has thin, flat rings.

Neptune, the eighth planet from the Sun, ranks fourth in size (average radius - 24,622 km) and third in mass (17 Earth). For a gas giant, it is relatively small (only four times the size of the Earth). Its atmosphere is also mainly composed of hydrogen, helium and methane. Gas clouds in its upper layers move at a record speed, the highest in the solar system - 2000 km / h! Some scientists believe that under the surface of the planet, under the thickness of frozen gases and water, hidden, in turn, by the atmosphere, a solid stone core can hide.

These two planets are close in composition, and therefore they are sometimes classified as a separate category - ice giants.

Minor planets

Small planets are called celestial bodies, which also move around the Sun in their own orbits, but differ from other planets in insignificant sizes. Previously, only asteroids were included in them, but more recently, namely, since 2006, Pluto, which was previously included in the list of planets in the solar system and was the last, tenth, belongs to them. This is due to changes in terminology. Thus, the minor planets now include not only asteroids, but also dwarf planets - Eris, Ceres, Makemake. They were named plutoids after Pluto. The orbits of all known dwarf planets are beyond the orbit of Neptune, in the so-called Kuiper belt, which is much wider and more massive than the asteroid belt. Although their nature, as scientists believe, is the same: it is the "unused" material left after the formation of the solar system. Some scientists have suggested that the asteroid belt is the debris of the ninth planet, Phaeton, which died as a result of a global catastrophe.

Pluto is known to be composed primarily of ice and solid rock. The main component of its ice sheet is nitrogen. Its poles are covered with eternal snows.

This is the order of the planets of the solar system, according to modern ideas.

Parade of planets. Types of parades

This is a very interesting phenomenon for those who are interested in astronomy. It is customary to call a parade of planets such a position in the solar system, when some of them, continuously moving along their orbits, for a short time occupy a certain position for an earthly observer, as if lining up along one line.

The visible parade of planets in astronomy is a special position of the five brightest planets of the solar system for people who see them from Earth - Mercury, Venus, Mars, as well as two giants - Jupiter and Saturn. At this time, the distance between them is relatively small and they are clearly visible in a small sector of the sky.

There are two types of parades. A big one is its appearance when five celestial bodies line up in one line. Small - when there are only four of them. These phenomena can be visible or invisible from different parts of the globe. At the same time, a large parade is quite rare - once every few decades. The small one can be observed once every few years, and the so-called mini-parade, in which only three planets participate, is almost every year.

Interesting facts about our planetary system

Venus, the only one of all the major planets in the solar system, rotates around its axis in the opposite direction to its rotation around the Sun.

The highest mountain on the major planets of the solar system is Olympus (21.2 km, diameter - 540 km), an extinct volcano on Mars. Not so long ago, on the largest asteroid in our star system, Vesta, a peak was discovered that somewhat exceeds Olympus in terms of parameters. Perhaps it is the highest in the solar system.

Jupiter's four Galilean moons are the largest in the solar system.

In addition to Saturn, all gas giants, some asteroids and Saturn's moon Rhea have rings.

What system of stars is closest to us? The solar system is closest to the star system of the triple star Alpha Centauri (4.36 light years). It is assumed that planets similar to Earth can exist in it.

To kids about planets

How to explain to children what the solar system is? Her model, which can be made with the kids, will help here. To create planets, you can use plasticine or ready-made plastic (rubber) balls, as shown below. At the same time, it is necessary to observe the ratio between the sizes of the “planets”, so that the model of the solar system really helps to form the correct ideas about space in children.

You will also need toothpicks that will hold our heavenly bodies, and as a background, you can use a dark sheet of cardboard with small dots imitating stars painted on with paint. With the help of such an interactive toy, it will be easier for children to understand what the solar system is.

The future of the solar system

The article described in detail what the solar system is. Despite its apparent stability, our Sun, like everything in nature, is evolving, but this process, by our standards, is very long. The supply of hydrogen fuel in its bowels is huge, but not infinite. So, according to the hypotheses of scientists, it will end in 6.4 billion years. As it burns out, the solar core will become denser and hotter, and the outer shell of the star will become wider and wider. The luminosity of the star will also increase. It is assumed that in 3.5 billion years, because of this, the climate on Earth will be similar to Venusian, and life on it in the usual sense for us will no longer be possible. There will be no water left at all; under the influence of high temperatures, it will evaporate into outer space. Subsequently, according to scientists, the Earth will be absorbed by the Sun and dissolved in its depths.

The outlook is not very bright. However, progress does not stand still, and, perhaps, by that time, new technologies will allow mankind to master other planets, over which other suns shine. After all, how many "solar" systems in the world, scientists do not yet know. There are probably countless of them, and among them it is quite possible to find one suitable for human habitation. Which "solar" system will become our new home is not so important. Human civilization will be preserved, and another page will begin in its history...

The new words didn't fit in my head. It also happened that the textbook of natural history set before us the goal - to remember the location of the planets of the solar system, and we were already choosing the means to justify it. Among the many options for solving this problem, there are several interesting and efficient ones.

Mnemonic in its purest form

The way out for modern students was invented by the ancient Greeks. No wonder the term "mnemonics" comes from a consonant Greek word, meaning in literal translation "the art of remembering." This art gave rise to a whole system of actions aimed at memorizing a large amount of information - "mnemonics".

They are very convenient to use if you just need to memorize a whole list of any names, a list of important addresses or phone numbers, or remember the sequence of objects. In the case of the planets of our system, such a technique is simply irreplaceable.

We play associations or "Ivan gave birth to a girl ..."

Each of us remembers and knows this rhyme since elementary school. This is the mnemonic counter. We are talking about that couplet, thanks to which it becomes easier for a child to remember the cases of the Russian language - “Ivan gave birth to a girl - He ordered to drag the diaper” (respectively - Nominative, Genitive, Dative, Accusative, Instrumental and Prepositional).

Is it possible to do the same with the planets of the solar system? - Undoubtedly. A mnemonic for this astronomical educational program has already been invented quite a large number. The main thing you need to know: they are all based on associative thinking. It is easier for someone to imagine an object similar in form to a memorized one, for someone it is enough to present a chain of names in the form of a kind of “cipher”. Here are just a few tips on how best to memorize their location, taking into account the distance from the central star.

Funny pictures

The sequence of removal of the planets of our star system from the Sun can be remembered through visual images. First, associate with each planet an image of an object or even a person. Then imagine these pictures one by one, in the sequence in which the planets are located inside the solar system.

1. Mercury. If you have never seen images of this ancient Greek god, try to remember the late lead singer of the Queen group - Freddie Mercury, whose last name is consonant with the name of the planet. It is unlikely, of course, that children can know who this uncle is. Then we propose to come up with simple phrases, where the first word would begin with the syllable MEP, and the second with KUR. And they must necessarily describe specific objects, which will then become a “picture” for Mercury (this method can be used as the most extreme option with each of the planets).
2. Venus. Many have seen the statue of Venus de Milo. If you show it to your children, they can easily remember this "armless aunt." Plus, enlighten the next generation. You can ask them to remember some friend, classmate or relative with that name - all of a sudden there are such in the circle of friends.
3. Earth. Everything is simple here. Everyone must imagine himself, an inhabitant of the Earth, whose “picture” stands between two planets located in space before and after ours.
4. Mars. In this case, advertising can become not only an "engine of trade", but also scientific knowledge. We think you understand that you need to introduce a popular imported chocolate in the place of the planet.
5. Jupiter. Try to imagine some landmark of St. Petersburg, for example, the Bronze Horseman. Yes, even if the planet begins in the south, but the locals call the "Northern Capital" Peter. Such an association may not be useful for children, so invent a phrase with them.
6. Saturn. Such a “handsome man” does not need any visual image, because everyone knows him as a planet with rings. If there are still difficulties, imagine a sports stadium with a treadmill. Moreover, such an association has already been used by the creators of one animated film on a space theme.
7. Uranus. The most effective in this case will be the “picture”, in which someone is very happy about some achievement and, as it were, shouts “Hurrah!”. Agree - every child is capable of adding one letter to this exclamation.
8. Neptune. Show the children the cartoon "The Little Mermaid" - let them remember Ariel's dad - the King with a mighty beard, impressive muscles and a huge trident. And it does not matter that according to the plot, His Majesty is called Triton. Neptune, after all, also had this tool in his arsenal.

And now - once again mentally imagine everything (or all) that reminds you of the planets of the solar system. Flip through these images, like pages in a photo album, from the first "picture", the closest to the Sun, to the last, whose distance from the star is the greatest.

“Look, what kind of POINTS have turned out ...”

Now - to mnemonics, which are based on the "initials" of the planets. Remembering the order of the planets in the solar system is really the easiest thing to do by the first letters. This kind of "art" is ideal for those who do not have such a brightly developed figurative thinking, but everything is in order with its associative form.

The most striking examples of versification in order to fix in memory the order of the planets are the following:

"The Bear Comes Out for Raspberries - The Lawyer Managed to Escape the Lowland";
"We All Know: Yulia's Mom Got on Stilts in the Morning."

You can, of course, not add up the rhyme, but simply pick up words that begin with the first letters in the names of each of the planets. A little advice: in order not to confuse Mercury and Mars, starting with the same letter, put the first syllables at the beginning of your words - ME and MA, respectively.

For example: In some places, Golden Cars were seen, Yulili As if Seeing Us.

You can come up with such proposals indefinitely - as long as your imagination is enough. In a word, try, train, remember ...

Questions:
1. Structure and composition of the solar system.
2. The birth of the solar system.
3. Planets of the Earth group: Mercury, Venus, Mars.
4. Planets of the Jupiter group.
5. The moon is a satellite of the Earth.
1. Structure and composition of the solar system

The solar system is a particle in the Milky Way galaxy.
The solar system is a system of celestial bodies welded together by the forces of mutual attraction. The planets included in the system move in almost the same plane and in the same direction in an elliptical orbit.
The existence of the solar system was first announced in 1543 by the Polish astronomer Nicolaus Copernicus, refuting the idea that had prevailed for several centuries that the Earth was the center of the universe.

The center of the solar system is the ordinary star the Sun, in which the bulk of the system's matter is concentrated. Its mass is 750 times the mass of all the planets in the solar system and 330,000 times the mass of the Earth. Under the influence of the gravitational attraction of the Sun, the planets form a group, rotating around its axis (each with its own speed) and making a revolution around the Sun without deviating from its orbit. The elliptical orbits of the planets are at different distances from our star.

The order of the planets:
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
According to physical characteristics, the large 8 planets are divided into two groups: the Earth and Mercury, Mars and Venus similar to it. The second group includes the giant planets: Jupiter, Saturn, Uranus and Neptune. The most distant planet Pluto, as well as 3 more planets discovered since 2006, are classified as minor planets of the solar system.
Planets of the 1st group (terrestrial type) consist of dense rocks, and the second - of gas, ice and other particles.

2. The birth of the solar system.

In the inner heated regions, dense blocks formed and coalesced with each other, forming terrestrial-type planets. Dust particles collided, broke up and stuck together again, forming lumps. They were too small, had a small gravitational field and could not attract the light gases hydrogen and helium. As a result, planets of the 1st type are small in volume, but very dense.
Farther from the center of the disk, the temperature was much lower. Volatile substances adhered to dust particles. The high content of hydrogen and helium served as the basis for the formation of giant planets. The planets formed there attracted gases to themselves. Currently, they also have extensive atmospheres.
Part of the gas and dust cloud turned into meteorites and comets. The constant bombardment of cosmic bodies by meteorites is a continuation of the process of formation of the Universe.

How did the solar system originate?

3. Planets of the Earth group: Mercury, Venus, Mars.
All terrestrial planets have a lithosphere - a solid shell of the planet, including the earth's crust and part of the mantle.
Venus, Mars, like the Earth, have an atmosphere that is similar in the presence of chemical elements to each other. The difference is only in the concentration of substances. On Earth, the atmosphere has changed due to the activity of living organisms. The basis of the atmosphere of Venus and Mars is carbon dioxide - 95%, and the Earth - nitrogen. The density of the Earth's atmosphere is 100 times less than Venus and 100 times greater than Mars. The clouds of Venus are concentrated sulfuric acid. A large amount of carbon dioxide can create a greenhouse effect, which is why there are such high temperatures.

Comparison of the sizes of the terrestrial planets (from left to right - Mercury, Venus, Earth, Mars)

Mercury.

Distance to the Sun: 57.9 million km

Diameter: 4.860 km

Period of rotation around the axis (day): 176

Per. revolutions around the Sun (year): 88 days.

Temperature: + 350-426 about C on the sunny side and - 180 about C for the night.

There is almost no atmosphere, there is a very weak magnetic field.

The average speed of the planet in orbit is 48 km / s, constantly changing. The axis of rotation of the planet is at almost a right angle to the plane of the orbit. The surface of Mercury is similar to the Moon. The surface was formed by volcanic activity and meteorite impacts due to the absence of an atmosphere. Craters vary in size from a few meters to hundreds of kilometers across. The largest crater on Mercury is named after the great Dutch painter Rembrandt, its diameter is 716 km. The phases of the moon are observed through a telescope. There are lowlands - "seas" and uneven hills - "continents". Mountain ranges reach a height of several kilometers. The sky on Mercury is black due to the highly rarefied atmosphere, which is almost non-existent.
Mercury has a large iron core, a rocky mantle, and a crust.

Venus.

Distance to the Sun: 108 million km

Diameter 12104 km

243 days

225 days

Axis of rotation vertical

Temperature: average + 464 about S.

Atmosphere: CO 2 97%.

Rotates clockwise

There are vast plateaus on Venus, mountain ranges located on them rise to a height of 7-8 km. The highest mountains are 11 km. There are traces of tectonic and volcanic activity. About 1000 craters of meteorite origin. 85% of the planet's surface is occupied by volcanic plains.
The surface of Venus is hidden by a dense cloud layer of sulfuric acid. The sun is barely visible in the dark orange sky. At night, the stars are not visible at all. Clouds go around the planet in 4-5 days. The thickness of the atmosphere is 250 km.
Structure of Venus: solid metal core, silicate mantle and crust. The magnetic field is almost absent.

Mars.

Distance to the Sun: 228 million km

Diameter: 6794km

Period of rotation around the axis (day): 24 h 37 min

Per. revolution around the Sun (year): 687 days

Temperature:Average - 60 about C;at the equator 0 o C; at the poles - 140 o C

Atmosphere: CO 2, the pressure is 160 times less than Earth's.

Moons: Phobos, Deimos.

The axial tilt of Mars is 25 degrees.
On the surface of Mars, one can distinguish "seas" of 2000 km and elevated areas - "continents". In addition to meteorite craters, giant volcanic cones 15-20 km high and 500-600 km in diameter have been discovered - Mount Olympus. The Mariner Valley is a giant canyon visible from space. Mountain ranges and canyons have been discovered. Screes, dunes, and other formations of atmospheric erosion speak of dust storms. The red color of Martian dust is the presence of iron oxide (limonite substance). Valleys that look like dry riverbeds are evidence that Mars was once warmer and water existed. She is still in the polar ice. And oxygen is in oxides.
The largest meteorite crater in the solar system has been discovered in the northern hemisphere of Mars. Its length is 10.6 thousand km, and its width is 8.5 thousand km.
The change of seasons causes the melting of the Martian glaciers, accompanied by the release of carbon dioxide and an increase in pressure in the atmosphere. As a result, winds and hurricanes appear, the speed of which reaches 10-40, and sometimes 100 m/s.
The structure of Mars: there is an iron core, mantle and crust.
Mars has two moons that are irregularly shaped. They are composed of carbon-rich rock and are thought to be asteroids captured by the gravity of Mars. The diameter of Phobos is about 27 km. It is the largest and closest satellite to Mars. The diameter of Deimos is about 15 km.

Distance to the Sun: 778 million km

Diameter: 143thousand km

Period of rotation around the axis (day): 9 h 50 min

Per. revolutions around the Sun (year): » 12 years

Temperature: -140 about C

Atmosphere: Hydrogen, methane, ammonia, helium.

A ring of dust and stones is barely noticeable

Satellites: 67 - Ganymede, Io, Europa, Callisto, etc.

The planet is rotating very fast. The axis is slightly tilted. Structure:
liquid hydrogen, liquid metallic hydrogen, iron core.
The atmosphere is gaseous: 87% consists of hydrogen, ammonia and helium are present. High pressure. Clouds of reddish ammonia, severe thunderstorms. The thickness of the cloud layer is 1000 km. Wind speed 100 m/s (650 km/h), cyclones (Great Red Spot 30 thousand km wide). The planet radiates heat, but thermonuclear reactions do not occur in the center, as in the Sun.
The rapid rotation of Jupiter and the heat emanating from within give rise to powerful atmospheric movements. Belts with different pressures (bands) appear in the atmosphere, hurricanes rage. The surface is liquid hydrogen with a temperature of –140 °C, seething. The density is 4 times less than the density of water - 1330 kg/m3. Inside the hydrogen ocean, the temperature is +11,000 °C. Liquefied hydrogen under high pressure becomes metallic (very dense), creates a strong magnetic field. The temperature of the core is 30 thousand ° C, it consists of iron.
Jupiter has a barely visible ring of dust and rocks. Reflecting from the ring, sunlight creates a halo - a glow. You cannot see the ring through a telescope - it is perpendicular.

As of January 2012, Jupiter has 67 known moons - the largest number among the planets of the solar system. The largest:
And about- the closest, makes a revolution around Jupiter in 42.5 hours. The density is high, there is iron in the core. Similar in size to the moon. Io is volcanically active, observation. 12 active volcanoes. Sulfur compounds colored the surface yellow-orange. The surface temperature near the volcanoes is 300 °C. Black seas of molten sulfur sway on the orange shores. It always faces Jupiter on the same side. Forms 2 tidal humps due to the force of gravity, which move, which led to the heating of the bowels.
Europe smaller than Io. It has a smooth surface, consisting of frozen water ice, dotted with cracks and streaks. The core is silicate, there are few craters. Europe is young in age - about 100 million years.
Ganymede is the largest satellite in the solar system. Its radius is 2.631 km. 4% of the surface is ice crust covered with craters. Age like Io. It has a stone core and a mantle of water ice. On the surface lies stone-ice dust.
Callisto is the 2nd largest moon of Jupiter. The surface is icy, heavily cratered, similar to Ganymede.
All satellites face Jupiter on the same side.

Saturn

Distance to the Sun: 9.54 AU (1 AU = 150 million km - the distance from the Earth to the Sun, used for long distances)

Diameter: 120.660 km

Period of rotation around the axis (day): 10.2 h

Per. revolutions in the district of the Sun (year): » 29.46 years old

Temperature: -180 about C

Atmosphere: Hydrogen 93%, methane, ammonia, helium.

Surface made of liquid hydrogen and helium

Satellites: 62.

Saturn is a light yellow ball of gas, composed of hydrogen and helium (mostly liquid molecular hydrogen). Due to the rapid rotation, the ball is strongly flattened at the poles. Day - 10 h 16 min. The core is made of iron. Saturn has a strong magnetic field generated by metallic hydrogen in the mantle. The surface of Saturn is liquid hydrogen. Ammonia crystals are concentrated near the surface, which prevent from seeing the surface from space.
Structure: core, liquid metallic hydrogen, liquid hydrogen, atmosphere.
The structure of the atmosphere is almost like that of Jupiter. It consists of 94-93% hydrogen, helium, ammonia, methane, water, impurities of phosphorus and other elements. Bands parallel to the equator are observed - giant atmospheric currents, the speed of which is 500 m / s.
Saturn has rings - the remains of a huge circumplanetary cloud, consisting of dust particles, ice and stones. The rings are younger than the planet. It is believed that these are the remains of an exploded satellite or a comet captured by Saturn. Banding is determined by the composition of the rings. The rings sway and bend under the gravitational pressure of the satellites. Particle speed 10 km/s. Lumps constantly collide and crumble, sticking together again. Their structure is loose. The thickness of the rings is 10-20 m, and the width is 60 thousand km.
Saturn has 62 moons made up of light-colored water ice. The satellites always face Saturn on the same side. Mimas has a huge crater 130 km wide, Tethys has two of its satellites, and Dione has one. The largest moon of Saturn is Titan. (2nd after Ganymede). Its diameter is 5.150 km (greater than Mercury). In structure, it is similar to Jupiterian: a stone core and an icy mantle. It has a powerful atmosphere of nitrogen and methane. The surface is an ocean of methane -180 °C. Phoebe is a distant satellite of Saturn that rotates in the opposite direction.

Uranus

Diameter: 51.200 km

Period of rotation around the axis (day): » 17h

Per. converted ia around the sun (year): 84 years old

Temperature: -218 °C

Atmosphere: hydrogen and helium - the main components, methane, ammonia, etc.

liquid hydrogen surface methane

Rings - 9 (11) rows

Satellites: 27 - Miranda, Ariel, Titania, Oberon, Umbriel and etc.

The planet is blue and green. This is due to the presence of methane in the atmosphere. Methane absorbs red light and reflects blue and green light. The atmosphere is made up of hydrogen, helium and methane. Its thickness is 8 thousand km. The surface is hidden from observation due to methane haze. The speed of clouds in the atmosphere is 10 m/s. The mantle of Uranus is a frozen ocean of water, ammonia and methane. Pressure 200 thousand earth atmospheres. The temperature is about - 200 °C. The iron silicate core has a temperature of 7.000°C.

Uranus has a strong magnetic field. Axis tilt 98°. Uranus has 27 satellites moving perpendicular to the orbit of the ecliptic. The most distant Oberon and Titania have an icy surface.
Uranus has narrow black rings arranged in 9 rows. They are made of stone. Thickness - tens of meters, with a radius of 40-50 thousand km. Satellites: 14 - Triton, Nereid, etc.

Similar in structure and composition to Uranus: core, icy mantle and atmosphere. Has a strong magnetic field. The atmosphere contains a lot of hydrogen, helium, and also more methane than Uranus, which is why the planet is blue. Atmospheric cyclones are noticeable - the Great Dark Spot with white clouds at the edges. On Neptune, the strongest winds in the solar system are 2200 km/h.
Neptune has 14 moons. Triton moves in the opposite direction to Neptune. Its diameter is 4950 km. It has an atmosphere, the surface temperature is 235-238 °C. Volcanically active - geysers.
Neptune has 4 rarefied narrow rings, which are visible to us in the form of arcs, because. maybe the substance is unevenly distributed. The rings are composed of ice particles or reddish silicates.
Structure: iron core, ice mantle and atmosphere (hydrogen, helium, methane). Pluto is a stone ball, the surface of which is covered with frozen gases - grayish methane ice. Planet diameter 2290 km . The atmosphere of methane and nitrogen is highly rarefied. The only satellite of Pluto is very large compared to the planet (Charon). Consists of water ice and reddish rocks. Surface temperature - 228 - 206°C. At the poles are caps of frozen gases. The sun from the surface of Pluto and Charon is seen in1000 times smaller than from Earth.

5. The moon is a satellite of the Earth

The only satellite of the Earth - the Moon lags behind it by 385,000 km. Glows with reflected light. Half the size of Pluto and nearly the size of Mercury. The diameter of the Moon is 3474 km (more than ¼ of the Earth). The mass is 1/81 of the mass of the Earth (7.34x1022 kg), and the force of gravity is 1/6 of the earth's gravity. The age of the Moon is 4.36 billion years. There is no magnetic field.
The moon makes a full revolution around the Earth in 27 days 7 hours 43 minutes. A day lasts 2 Earth weeks. There is no water and air on the Moon, therefore, on a lunar day, the temperature is + 120 ° C, and at night it drops to - 160 ° C.

The moon has a core and a thick crust about 60 km thick. Therefore, the Moon and the Earth have a similar origin. An analysis of the soil delivered by American astronauts on the Apollo spacecraft showed that it contains minerals similar to those of the earth. The soil is poorer in terms of the amount of minerals, because. there is no water that creates oxides.

Samples of lunar rock indicate that it was formed from a molten, cooled and crystallized mass. Lunar soil - regolith - is a finely divided substance formed as a result of constant bombardment of the surface by cosmic bodies. The surface of the moon is dotted with craters (there are 30 thousand of them). One of the large craters is located on the far side of the satellite, it reaches 80 km in diameter. The craters are named after famous scientists, figures from different eras: Plato, Aristotle, Copernicus, Galileo, Lomonosov, Gagarin, Pavlov and others.
The light areas of the Moon are called "land", and the dark areas - depressions - "seas" (Ocean of Storms, Sea of ​​Rains, Sea of ​​Tranquility, Gulf of Heat, Sea of ​​Crises, etc.). There are mountains and even mountain ranges on the Moon. They are named as on Earth: the Alps, the Carpathians, the Caucasus, the Pyrenees.
On the Moon, surface cracking can be observed due to sudden temperature changes, moonquakes. In the cracks - frozen lava.

There are three hypotheses for the origin of the moon.
1. "Capture". A space body flying past was captured by the forces of gravity of the Earth and turned into a satellite.
2 sisters". The Earth and the Moon were formed from one clot of matter, but each developed on its own in close proximity to each other.
3. "Mother and daughter." Once upon a time, part of the matter separated from the Earth, leaving a deep depression (in the place of the Pacific Ocean). Space images of the Moon's surface and analysis of the soil show that it was formed under the influence of high temperatures as a result of the impact of cosmic bodies. This means that this separation occurred a very long time ago. According to this hypothesis, 4 billion years ago, a huge asteroid or a small planet crashed into the Earth. Broken off pieces of the earth's crust and the "wanderer" scattered into debris into space. Under the influence of gravitational forces, a satellite formed over time. The correctness of this hypothesis is proved by two facts: a small amount of iron on the Moon and the presence of two dust satellites rotating in a lunar orbit (observed in 1956).

Origin of the Moon

The moon also influences the earth. It affects our well-being, causes ebb and flow. This is due to the strengthening of the action of the Moon by the Sun when they are in the same plane.
The lunar face is constantly changing. This is due to the different position of the moon relative to the luminary.
A full cycle of the phase of the moon takes 29.5 days. Each phase lasts about a week.
1. New Moon - The moon is not visible.
2. First quarter - from a thin crescent on the right to a semicircle.
3. Full moon - round moon.
4. Last quarter - reduction from half to a narrow crescent.

Moon eclipse occurs when the Earth is in a straight line between the Sun and the Moon. The moon is in the shadow of the earth. The earth's atmosphere allows only red rays to reach the moon, so the moon appears red. This event lasts approximately one and a half hours.

solar eclipsehappens when The Moon covers the Sun with its disk. A total eclipse at one point on the globe is rare. You can see partial solar eclipses, which are more common. The shadow of the moon has length 250 km . Duration 7 min 40 sec.

The solar system is the central star the Sun and all the cosmic bodies that revolve around it.

There are 8 largest celestial bodies, or planets, in the solar system. Our Earth is also a planet. In addition to it, 7 more planets make their journey in space around the Sun: Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune. The last two can only be observed with a telescope from Earth. The rest are visible to the naked eye.

More recently, another celestial body, Pluto, was ranked among the planets. It is very far from the Sun, beyond the orbit of Neptune, and was discovered only in 1930. However, in 2006, astronomers introduced a new definition of a classical planet, and Pluto did not fall under it.

The planets have been known to people since ancient times. The nearest neighbors of the Earth are Venus and Mars, the most distant from it are Uranus and Neptune.

Large planets are usually divided into two groups. The first group includes the planets that are closest to the Sun: these are terrestrial planets, or inner planets, - Mercury, Venus, Earth and Mars. All these planets have a high density and a solid surface (although there is a liquid core under it). The largest planet in this group is Earth. However, the planets farthest from the Sun - Jupiter, Saturn, Uranus and Neptune are much larger than the Earth in size. That's why they got the name giant planets. They are also called outer planets. Thus, the mass of Jupiter exceeds the mass of the Earth by more than 300 times. The giant planets differ significantly from the terrestrial planets in their structure: they do not consist of heavy elements, but of gas, mainly hydrogen and helium, like the Sun and other stars. Giant planets do not have a solid surface - they are just balls of gas. Therefore they are also called gas planets.

There is a belt between Mars and Jupiter asteroids, or minor planets. An asteroid is a small planet-like body in the solar system, ranging in size from a few meters to a thousand kilometers. The largest asteroids in this belt are Ceres, Pallas and Juno.

Beyond the orbit of Neptune is another belt of small celestial bodies, which is called the Kuiper belt. It is 20 times wider than the asteroid belt. Pluto, which lost its planet status and was relegated to dwarf planets, just located in this belt. There are other dwarf planets in the Kuiper belt, similar to Pluto, in 2008 they were named as such - plutoids. These are Makemake and Haumea. By the way, Ceres from the asteroid belt is also classified as a dwarf planet (but not plutoid!).

Another plutoid - Eris - is comparable in size to Pluto, but is located much further from the Sun - beyond the Kuiper belt. Interestingly, Eris was at one time even a candidate for the role of the 10th planet in the solar system. But as a result, it was the discovery of Eris that caused the revision of the status of Pluto in 2006, when the International Astronomical Union (IAU) introduced a new classification of the celestial bodies of the solar system. According to this classification, Eris and Pluto did not fall under the concept of a classical planet, but "deserved" only the title of dwarf planets - celestial bodies that revolve around the Sun, are not planetary satellites and have a large enough mass to maintain an almost rounded shape, but, unlike the planets, they are not able to clear their orbit from other space objects.

The composition of the solar system, in addition to the planets, includes their satellites that revolve around them. There are now 415 satellites in total. The Moon is the constant companion of the Earth. Mars has 2 moons - Phobos and Deimos. Jupiter has 67 moons and Saturn has 62. Uranus has 27 moons. And only Venus and Mercury have no satellites. But the "dwarfs" of Pluto and Eris have satellites: Pluto has Charon, and Eris has Dysnomia. However, astronomers have not yet come to the final conclusion whether Charon is a satellite of Pluto or the Pluto-Charon system is the so-called double planet. Even some asteroids have moons. The champion in size among satellites is Ganymede, a satellite of Jupiter, not far behind Saturn's satellite Titan. Both Ganymede and Titan are larger than Mercury.

In addition to planets and satellites, dozens, if not hundreds of thousands of different small bodies: tailed celestial bodies - comets, a huge number of meteorites, particles of gas and dust matter, scattered atoms of various chemical elements, streams of atomic particles and others.

All objects of the solar system are held in it due to the force of gravity of the sun, and they all revolve around it, and in the same direction with the rotation of the sun itself and practically in the same plane, which is called plane of the ecliptic. The exception is some comets and Kuiper belt objects. In addition, almost all objects of the solar system also rotate around their axis, and in the same direction as around the sun (the exceptions are Venus and Uranus; the latter even rotates "lying on its side").

Pluto's orbit is highly inclined relative to the ecliptic (by 17°) and highly elongated

Almost the entire mass of the solar system is concentrated in the Sun - 99.8%. The four largest objects - gas giants - make up 99% of the remaining mass (with most - about 90% - falling on Jupiter and Saturn). As for the size of the solar system, astronomers have not yet come to a consensus on this issue. According to modern estimates, the size of the solar system is at least 60 billion kilometers. In order to at least approximately imagine the scale of the solar system, we will give a more illustrative example. Within the solar system, an astronomical unit (AU) is taken as a unit of distance - the average distance from the Earth to the Sun. It is approximately 150 million km (light travels this distance in 8 min 19 s). The outer boundary of the Kuiper belt is located at a distance of 55 AU. e. from the Sun.

Another way to imagine the actual dimensions of the solar system is to imagine a model in which all dimensions and distances are reduced to a billion times . In this case, the Earth will be about 1.3 cm in diameter (the size of a grape). The moon will rotate at a distance of about 30 cm from it. The sun will be 1.5 meters in diameter (about the height of a person) and 150 meters from Earth (about a city block). Jupiter is 15 cm in diameter (the size of a large grapefruit) and 5 city blocks from the Sun. Saturn (the size of an orange) is 10 blocks away. Uranus and Neptune (lemons) - 20 and 30 quarters. A person on this scale would be the size of an atom; and the nearest star is at a distance of 40,000 km.

The composition of the solar system includes: the Sun - the central body; nine large planets with their satellites (more than 60); small planets - asteroids (50-60 thousand); comets and meteoroids (meteorites and meteors).

The sun is the star closest to us. The distance from the Earth to the Sun is 149.6 million kilometers. This distance is conditionally called one astronomical unit - 1 AU. Light travels through it in 8 minutes and 19 seconds.

The mass of the Sun is 770 times the mass of all the planets combined. The volume of the Sun could fit 1 million such balls as the Earth. The Sun contains 99.9% of the entire mass of the solar system.

The Sun is a huge plasma ball (its radius is approximately 700,000 km), consisting of 80% hydrogen and almost 20% helium. Thermonuclear reactions take place in the bowels of the Sun: hydrogen turns into helium, which is accompanied by a colossal release of energy.

The temperature on the surface of the Sun is approximately 6000 ° C, and in its depths - 15-20 million degrees.

The intensity of the processes occurring on the surface of the Sun changes periodically, while they say that solar activity changes. The period of change in solar activity is on average 11 years. Simultaneously with the eleven-year cycle, a secular, more precisely, 80-90-year cycle of solar activity takes place. Inconsistently superimposed on each other, they introduce noticeable changes in the processes taking place in the geographical envelope.

The following physical phenomena are put in causal dependence on the degree of intensity of solar activity: magnetic storms, aurora frequencies, the amount of ultraviolet radiation, the intensity of thunderstorm activity, air temperature, atmospheric pressure, precipitation, etc. Ultimately, a change in solar activity can affect climate change, on the growth of wood, the mass appearance of pests of forests and agricultural crops, the reproduction of rodents, commercial fish, etc. Many human diseases (cardiovascular, neuropsychiatric, viral, etc.) are associated with the periodic activity of the Sun.

Around the Sun, according to the laws of celestial mechanics, eight large planets move: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

In accordance with the laws of I. Kepler, firstly, each planet circulates along an ellipse, in one of the focuses of which is the Sun; secondly, the radius vector of the planet describes equal areas in equal time intervals (i.e., planets move faster near the Sun than away from it); thirdly, the ratio of the cubes of the semi-major axes of the orbits of any two planets in the solar system is equal to the ratio of the squares of their revolutions around the Sun.

The motion of the planets is subject to the law of universal gravitation, discovered by I. Newton. According to this law, all bodies interact with each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them:

F= f ---------, where f is a constant value, m 1 and m 2 are the masses of two mutual

acting bodies, r is the distance between them.

According to their size and physico-chemical properties, the planets are divided into two groups: 1) the planets of the "terrestrial" group (Mercury, Venus, Earth, Mars) are relatively small in size, have a relatively short period of revolution around the Sun, have a high density of matter (from 4, 0 to 5.5 g/cm3); 2) giant planets (Jupiter, Saturn, Uranus, Neptune) have gigantic dimensions, low density (1.3–1.6 g/cm 3), chemical composition of the same type, and a large number of satellites. Pluto should be attributed to the third group, because. in size, it adjoins the planets of the "terrestrial" group, and in physical and chemical properties it approaches the giant planets. Probably, beyond the orbit of Pluto, there may be other bodies whose orbits are highly elongated ellipses.

In relation to the Earth's orbit, the planets are also divided into two groups: 1) internal (Mercury, Venus) are always near the Sun and therefore they can be observed in the sky either in the east before sunrise, or in the west after sunset; 2) external (Mars, Jupiter, Saturn, Uranus, Neptune, only the first three are visible to the naked eye, the rest can only be observed through a telescope.

Mercury - the planet closest to the Sun (the distance is almost 58 million km or 0.4 AU). The period of revolution around the Sun is 88 days. The atmosphere is very rarefied (practically it does not exist, because the force of gravity is small and cannot hold the gaseous shell). The temperature on the sunny side is +400 o C (at night it is below -100 o C). The surface resembles a lunar landscape, as heavily pitted with craters.

Venus - the planet closest to the Earth, its dimensions are almost the same as those of the Earth (the diameter of Venus is about 12,112 km). The distance from the Sun to Venus is 108 million km (0.7 AU); the circulation period is 225 days. Venus has a powerful atmosphere consisting of carbon dioxide (97%), nitrogen, inert gases, etc. Carbon dioxide and water vapor (0.1%) create a greenhouse effect, as a result of which the temperature on Venus is almost +500 ° C. The surface of the planet always hidden from observers by a dense layer of clouds.

Earth - the third planet from the Sun (the distance to the Sun is approximately 150 million km, or 1 AU). The average diameter of the Earth is about 12,742 km; the period of revolution around the sun is 1 year. The Earth has 1 satellite - the Moon. (For more details, see the chapter "Characterization of the Earth as a planet").

Mars - the fourth planet from the Sun (the distance to the Sun is about 228 million km, or 1.5 AU; the period of revolution is approximately 2 years). Mars is half the diameter of Earth. Its atmosphere consists of carbon dioxide, argon, etc., its density is less than that of the earth (atmospheric pressure near the surface of Mars is the same as on Earth at an altitude of 35 km). The temperature ranges from +20 o C to -120 o C. The surface of Mars has a reddish tint, and white caps are visible at the poles (probably from frozen carbon dioxide). Since Mars has an axial tilt the same as that of the Earth, the change of seasons (melting of “caps”) is well expressed on it. Mars has two moons: Phobos and Deimos.

Jupiter is the largest planet in the solar system. The distance to the Sun is 780 million km (5 AU), the period of revolution is approximately 12 years. Jupiter is 11 times the diameter of Earth. Due to the rapid rotation around its axis, Jupiter is strongly compressed at the poles. Its atmosphere consists of hydrogen, helium, methane, ammonia. The temperature is -140 o C. Jupiter has a system of small rings and 16 satellites (Io, Europa, Callisto, Ganymede, etc.), and Ganymede and Callisto are larger than the planet Mercury.

Saturn is the second largest planet in the solar system. The distance to the Sun is 1 billion 430 million km (10 AU), the period of revolution is about 30 years. The atmosphere in terms of gas composition is close to the atmosphere of Jupiter; temperature -170 o C. Saturn has a system of rings (external, middle, internal). The rings are not solid, they are a collection of bodies revolving around the planet. Saturn has 18 satellites (Titan, Janus, Rhea, etc.).

Uranus - the seventh planet from the Sun (the distance to the Sun is 2 billion 869 million km, or 19 AU; the period of revolution is approximately 84 years). The atmosphere is similar to the atmospheres of other giant planets, the temperature is -215 o C. Uranus has a system of small rings and 17 satellites (Ariel and others).

Neptune located at a distance of 4 billion 497 million km from the Sun (30 AU), the period of its revolution is 165 years. In terms of size and physical conditions, Neptune is close to Uranus. It has 11 satellites (Triton, Nereid, etc.).

In addition to the major planets, around the Sun move and minor planets - asteroids . They form an independent belt between the orbits of Mars and Jupiter. Asteroids do not have a specific shape, but are angular blocks or debris. It is likely that these are fragments of a small destroyed planet. Their orbits are quite elliptical. About 2000 large asteroids are known (Ceres, Vesta, Pallas, Juno, etc.), and their total number is more than 60 thousand.

Comets (translated from Greek means tailed). Most comets move around the Sun in highly elongated elliptical orbits. According to the hypothesis of the Dutch scientist Oort, clots of matter remained on the outskirts of the solar system, from which comets were formed (“Oort cloud”). Some comets are aliens from space, their orbits are parabolas and hyperbolas. Comets have the appearance of nebulous objects with a luminous core in the center and a tail, the length of which increases as the comet approaches the Sun. Comets consist of frozen stones and gases (CO, CO 2, N 2, CH, etc.). When approaching the Sun, a gas shell is formed around the comet's nucleus (a head that can be the size of the Sun) and a tail - evaporating gases (the length of the tail can reach tens of millions of km). The most famous is Halley's comet with a period of revolution around the Sun of 76 years (the last time it passed near the Earth in 1986. At the end of March 1996, a comet passed near the Earth, which was visible to the naked eye. In 1997, in March-April, the comet Hoyl was observed -Bopp This comet was discovered in July 1995 by American scientists A. Hoyle and T. Bopp. It turned out that this comet has an elliptical orbit with a period of about 3000 years. On March 23, 1997, the comet passed the Earth at a distance of 195 million years. km, at this time the brightness of the comet reached its maximum.Thus, in late March - early April 1997, the comet Hoyle-Bopp was also clearly visible in the sky.

Meteor bodies are meteorites and meteors. Meteorites are bodies coming from interplanetary space, they fall out in the form of fragments. Large meteorites are called fireballs. It is believed that meteorites are fragments of asteroids. Meteors are the smallest solid particles that invade the Earth's atmosphere (observed as "shooting" stars). Their origin is associated with the decayed nuclei of comets. Especially a lot of meteors appear every year in early January, late April, mid-August and mid-November (“meteor showers”). Several tons of meteoritic matter falls to Earth every year.