How are the planets arranged in order? Planets of the Solar System: the process of emergence

The sun is ordinary star, its age is about 5 billion years. All the planets revolve in this star solar system.
THE SUN, the central body of the Solar System, a hot plasma ball, a typical dwarf star of spectral class G2; mass M~2.1030 kg, radius R=696 t. km, average density 1,416.103 kg/m3, luminosity L=3.86.1023 kW, effective surface (photospheric) temperature approx. 6000 K.

The rotation period (synodic) varies from 27 days at the equator to 32 days at the poles, the acceleration of gravity is 274 m/s2. Chemical composition determined from solar spectrum analysis: hydrogen approx. 90%, helium 10%, other elements less than 0.1% (by number of atoms).

The source of solar energy is the nuclear transformation of hydrogen into helium in the central region of the Sun, where the temperature is 15 million K (thermonuclear reactions).

Energy from the interior is transferred by radiation, and then in the outer layer with a thickness of approx. 0.2 R by convection. The existence of photospheric granulation, sunspots, spicules, etc. is associated with the convective motion of plasma.
The intensity of plasma processes on the Sun changes periodically (11-year period; see C

solar activity). The solar atmosphere (chromosphere and solar corona) is very dynamic, flares and prominences are observed in it, and there is a constant outflow of corona matter into interplanetary space (solar wind).

Features of the movement Venus moves in an orbit located between the orbits of Mercury and the Earth, with a sidereal period equal to 224.7 Earth days. ;
- Third Earth. The only planet on which life exists. Thanks to its unique, perhaps unique in the Universe natural conditions, became the place where organic life arose and developed. Shape, size and movement of the Earth The shape of the Earth is close to an ellipsoid, flattened at the poles and stretched in the equatorial zone. ;
- the fourth from the solar system. Behind it is the asteroid belt.

The average distance from the Sun is 228 million km, the orbital period is 687 days, the rotation period is 24.5 hours, the average diameter is 6780 km, the mass is 6.4×1023 kg; 2 natural satellite Phobos and Deimos. Atmospheric composition: CO2 (>95%), N2 (2.5%), Ar (1.5-2%), CO (0.06%), H2O (up to 0.1%); surface pressure 5-7 hPa. Areas of the surface of Mars covered with craters are similar to the lunar continent. Significant scientific material about Mars was obtained using the Mariner and Mars spacecraft.

Movement, size, mass Mars moves around the Sun in an elliptical orbit with an eccentricity of 0.0934. The orbital plane is inclined to the ecliptic plane at a slight angle (1° 51). ;
- the fifth from the sun of our solar system. the average distance from the Sun is 5.2 a. e. (778.3 million km), sidereal period of revolution 11.9 years, rotation period (cloud layer near the equator) approx. 10 h, equivalent diameter approx. 142,800 km, weight 1.90 1027 kg.

Atmospheric composition: H2, CH4, NH3, He. Jupiter is a powerful source of thermal radio emission, has a radiation belt and an extensive magnetosphere. Jupiter has 16 moons;
— Saturn is the sixth planet from the sun in our solar system. Orbital period 29.46 years, rotation period

at the equator (cloud layer) 10.2 hours, equatorial diameter 120,660 km, mass 5.68·1026 kg, has 17 satellites, the atmosphere includes CH4, H2, He, NH3. Radiation belts have been discovered around Saturn. having rings. SATURN, second largest after Jupiter big planet Solar System; belongs to the giant planets.

Motion, Dimensions, Shape Saturn's elliptical orbit has an eccentricity of 0.0556 and an average radius of 9.539 AU. e. (1427 million km). The maximum and minimum distances from the Sun are approximately 10 and 9 AU. e. Distances from the Earth vary from 1.2 to 1.6 billion km.

The inclination of the planet's orbit to the ecliptic plane is 2°29.4. ;
- the seventh from the sun of our solar system. Refers to the giant planets, the average distance from the Sun is 19.18 AU. e. (2871 million km), orbital period 84 years, rotation period approx. 17 hours, equatorial diameter 51,200 km, mass 8.7·1025 kg, atmospheric composition: H2, He, CH4. Uranus' rotation axis is tilted at an angle of 98°. Uranus has 15 satellites (5 discovered from Earth by Miranda, Ariel, Umbriel, Titania, Oberon, and 10 discovered by the Voyager 2 spacecraft: Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Belinda, Peck) and ring system. Movement, size, mass Uranus moves around the Sun in an elliptical orbit, the semi-major axis of which (average heliocentric distance) is 19.182 greater than that of the Earth, and amounts to 2871 million km. ;
- the eighth from the sun of our solar system. Orbital period 164.8 years, rotation period 17.8 hours, equatorial diameter 49,500 km, mass 1.03.1026 kg, atmospheric composition: CH4, H2, He. Neptune has 6 satellites.

Discovered in 1846 by I. Galle according to the theoretical predictions of W. J. Le Verrier and J. C. Adams. Neptune's distance from Earth significantly limits the possibilities of its exploration. NEPTUNE, the eighth major planet from the Sun in the Solar System, belongs to the giant planets. Some parameters of the planet Neptune moves around the Sun in an elliptical, close to circular (eccentricity 0.009) orbit; its average distance from the Sun is 30.058 times greater than that of the Earth, which is approximately 4500 million km. This means that light from the Sun reaches Neptune in a little over 4 hours. ;
- the ninth from the sun of our solar system. The average distance from the Sun is 39.4 a. e., orbital period 247.7 years, rotation period 6.4 days, diameter approx. 3000 km, weight approx. 1.79.1022 kg. Methane has been discovered on Pluto. Pluto is a double planet, its satellite, approximately 3 times smaller in diameter, moves at a distance of only approx. 20,000 km from the center of the planet, making 1 revolution in 6.4 days. Some parameters of the planet Pluto moves around the Sun in an elliptical orbit with a significant eccentricity of 0.25, exceeding even the eccentricity of the orbit of Mercury (0.206).

The semimajor axis of Pluto's orbit is 39.439 AU. e. or approximately 5.8 billion km. The orbital plane is inclined to the ecliptic at an angle of 17.2°. One rotation of Pluto lasts 247.7 Earth years;
, their satellites, many small planets, comets, small meteoroids and cosmic dust moving in the region of the prevailing gravitational action of the Sun. According to prevailing scientific ideas, the formation of the Solar system began with the emergence of the central body of the Sun;

The gravitational field of the Sun led to the capture of an incident gas-dust cloud, from which the formation of the Solar System occurred as a result of gravitational separation and condensation. The pressure of radiation from the Sun caused the heterogeneity of its chemical composition: lighter elements, primarily hydrogen and helium, predominate in the peripheral (so-called outer, or distant) planets. The age of the Earth is most reliably determined: it is approximately 4.6 billion years.

The general structure of the solar system was revealed in the mid-16th century. N. Copernicus, who substantiated the idea of the movement of planets around the Sun. Such solar system model called heliocentric. In the 17th century I. Kepler discovered the laws of planetary motion, and I. Newton formulated the law universal gravity. Studying physical characteristics space bodies that make up the solar system became possible only after the invention of the telescope by G. Galileo in 1609. Thus, by observing sunspots, Galileo first discovered the rotation of the Sun around its axis.

Theories on how it arose , a great many. The first of these was the famous theory put forward by the German philosopher Immanuel Kant in 1755. He believed that the emergence solar system originated from some primary matter, before which it was freely dispersed in space.

One of the subsequent cosmogonic theories is the theory of “catastrophes”. According to it, our planet Earth was formed after some kind of external intervention, for example, a meeting of the Sun with some other star, this meeting could cause the eruption of a certain part of the solar substance. Due to incandescence, gaseous matter quickly cooled and became denser, while forming many small solid particles, their accumulations were a kind of embryos of planets.

Planets of the solar system

The central body in our system is the Sun. It belongs to the class of yellow dwarf stars. The Sun is the most massive object in our planetary system. The closest star to Earth, as well as the main body in our planetary system. In our system, the planets are more or less ordinary. There are none, for example, that almost do not reflect light. Images of planets are often used in interior signs.

The very first planet from the Sun in our solar system is Mercury - it is also the smallest planet in the terrestrial group (in addition to Earth and Mercury, it includes Mars and Venus).

Next, second in line, comes Venus. Next comes the Earth - the shelter of all humanity. Our planet has a satellite - the Moon, which is almost 80 times lighter than the Earth. The Moon is the only satellite of the Earth orbiting the Earth. After the Sun, it is the brightest object in the sky. The fourth planet is Mars - this desert planet has two satellites. What follows large group planets are the so-called giant planets.

The sun and other planets played a big role in different. There were many religions that worshiped the Sun. And astrology, which studies the effect of planets on humans, still influences many people. Astrology used to be considered a science, but nowadays many people consider it a science.

The largest and most massive of all the giants is Jupiter, which represents our solar system in miniature. Jupiter has more than 40 satellites, the largest of which are Ganymede, Io, Europa, and Callisto. These satellites have another name - Galilean, in honor of the man who discovered them - Galileo Galilei.

Next comes the giant planet Uranus - it is unusual in that it has a “lying on its side” position - which is why there is a rather sharp change in seasons on Uranus. Has 21 satellites and distinctive feature in the form of rotation in the opposite direction.

The last giant planet is Neptune (Neptune’s largest satellite is Triton). All giant planets have distinctive feature in the form of many satellites, as well as a system of rings.

But the farthest and last planet in the solar system is Pluto, which is also the smallest planet in our system. Pluto has one satellite, Charon, which is slightly smaller than the planet itself.

Universe (space)- this is the entire world around us, limitless in time and space and infinitely varied in the forms that eternally moving matter takes. The boundlessness of the Universe can be partially imagined on a clear night with billions of different sizes of luminous flickering points in the sky, representing distant worlds. Rays of light at a speed of 300,000 km/s from the most distant parts of the Universe reach the Earth in about 10 billion years.

According to scientists, the Universe was formed as a result of “ Big Bang» 17 billion years ago.

It consists of clusters of stars, planets, cosmic dust and other cosmic bodies. These bodies form systems: planets with satellites (for example, the solar system), galaxies, metagalaxies (clusters of galaxies).

Galaxy(late Greek galaktikos- milky, milky, from Greek gala- milk) is a vast star system that consists of many stars, star clusters and associations, gas and dust nebulae, as well as individual atoms and particles scattered in interstellar space.

There are many galaxies of different sizes and shapes in the Universe.

All stars visible from Earth are part of the galaxy Milky Way. It got its name due to the fact that most stars can be seen on a clear night in the form of the Milky Way - a whitish, blurry stripe.

In total, the Milky Way Galaxy contains about 100 billion stars.

Our galaxy is in constant rotation. The speed of its movement in the Universe is 1.5 million km/h. If you look at our galaxy from its north pole, the rotation occurs clockwise. The Sun and the stars closest to it complete a revolution around the center of the galaxy every 200 million years. This period is considered galactic year.

Similar in size and shape to the Milky Way galaxy is the Andromeda Galaxy, or Andromeda Nebula, which is located at a distance of approximately 2 million light years from our galaxy. Light year— the distance traveled by light in a year, approximately equal to 10 13 km (the speed of light is 300,000 km/s).

To visualize the study of the movement and location of stars, planets and other celestial bodies, the concept of the celestial sphere is used.

Rice. 1. Main lines of the celestial sphere

Celestial sphere is an imaginary sphere of arbitrarily large radius, in the center of which the observer is located. The stars, Sun, Moon, and planets are projected onto the celestial sphere.

The most important lines on the celestial sphere are: the plumb line, zenith, nadir, celestial equator, ecliptic, celestial meridian, etc. (Fig. 1).

Plumb line- a straight line passing through the center of the celestial sphere and coinciding with the direction of the plumb line at the observation point. For an observer on the Earth's surface, a plumb line passes through the center of the Earth and the observation point.

A plumb line intersects the surface of the celestial sphere at two points - zenith, above the observer's head, and nadire - diametrically opposite point.

The great circle of the celestial sphere, the plane of which is perpendicular to the plumb line, is called mathematical horizon. It divides the surface of the celestial sphere into two halves: visible to the observer, with the vertex at the zenith, and invisible, with the vertex at the nadir.

The diameter around which the celestial sphere rotates is axis mundi. It intersects with the surface of the celestial sphere at two points - north pole of the world And south pole peace. North Pole is called the one from whose side the rotation of the celestial sphere occurs clockwise, if you look at the sphere from the outside.

The great circle of the celestial sphere, the plane of which is perpendicular to the axis of the world, is called celestial equator. It divides the surface of the celestial sphere into two hemispheres: northern, with its summit at the north celestial pole, and southern, with its peak at the south celestial pole.

The great circle of the celestial sphere, the plane of which passes through the plumb line and the axis of the world, is the celestial meridian. It divides the surface of the celestial sphere into two hemispheres - eastern And western.

The line of intersection of the plane of the celestial meridian and the plane of the mathematical horizon - noon line.

Ecliptic(from Greek ekieipsis- eclipse) is a large circle of the celestial sphere along which the visible annual movement of the Sun, or more precisely, its center, occurs.

The plane of the ecliptic is inclined to the plane of the celestial equator at an angle of 23°26"21".

To make it easier to remember the location of stars in the sky, people in ancient times came up with the idea of combining the brightest of them into constellations.

Currently, 88 constellations are known, which bear the names of mythical characters (Hercules, Pegasus, etc.), zodiac signs (Taurus, Pisces, Cancer, etc.), objects (Libra, Lyra, etc.) (Fig. 2).

Rice. 2. Summer-autumn constellations

Origin of galaxies. The solar system and its individual planets still remain an unsolved mystery of nature. There are several hypotheses. It is currently believed that our galaxy was formed from a gas cloud consisting of hydrogen. At the initial stage of galaxy evolution, the first stars formed from the interstellar gas-dust medium, and 4.6 billion years ago, the Solar System.

Composition of the solar system

The set of celestial bodies moving around the Sun as a central body forms Solar system. It is located almost on the outskirts of the Milky Way galaxy. The solar system is involved in rotation around the center of the galaxy. The speed of its movement is about 220 km/s. This movement occurs in the direction of the constellation Cygnus.

The composition of the Solar System can be represented in the form of a simplified diagram shown in Fig. 3.

Over 99.9% of the mass of matter in the Solar System comes from the Sun and only 0.1% from all its other elements.

Hypothesis of I. Kant (1775) - P. Laplace (1796)	Hypothesis of D. Jeans (early 20th century)	Hypothesis of Academician O.P. Schmidt (40s of the XX century)	Hypothesis akalemic by V. G. Fesenkov (30s of the XX century)
Planets were formed from gas-dust matter (in the form of a hot nebula). Cooling is accompanied by compression and an increase in the speed of rotation of some axis. Rings appeared at the equator of the nebula. The substance of the rings collected into hot bodies and gradually cooled	A larger star once passed by the Sun, and its gravity pulled out a stream of hot matter (prominence) from the Sun. Condensations formed, from which planets were later formed.	The gas and dust cloud revolving around the Sun should have taken on a solid shape as a result of the collision of particles and their movement. The particles combined into condensations. The attraction is more fine particles the condensations were supposed to promote the growth of the surrounding matter. The orbits of the condensations should have become almost circular and lying almost in the same plane. Condensations were the embryos of planets, absorbing almost all the matter from the spaces between their orbits	The Sun itself arose from the rotating cloud, and the planets emerged from secondary condensations in this cloud. Further, the Sun greatly decreased and cooled to its present state

Rice. 3. Composition of the Solar System

Sun

Sun- this is a star, a giant hot ball. Its diameter is 109 times the diameter of the Earth, its mass is 330,000 times the mass of the Earth, but its average density is low - only 1.4 times the density of water. The Sun is located at a distance of about 26,000 light years from the center of our galaxy and revolves around it, making one revolution in about 225-250 million years. The orbital speed of the Sun is 217 km/s—so it travels one light year every 1,400 Earth years.

Rice. 4. Chemical composition of the Sun

The pressure on the Sun is 200 billion times higher than at the surface of the Earth. The density of solar matter and pressure quickly increase in depth; the increase in pressure is explained by the weight of all overlying layers. The temperature on the surface of the Sun is 6000 K, and inside it is 13,500,000 K. The characteristic lifetime of a star like the Sun is 10 billion years.

Table 1. General information about the sun

The chemical composition of the Sun is about the same as that of most other stars: about 75% hydrogen, 25% helium and less than 1% all others chemical elements(carbon, oxygen, nitrogen, etc.) (Fig. 4).

The central part of the Sun with a radius of approximately 150,000 km is called the solar core. This is a zone of nuclear reactions. The density of the substance here is approximately 150 times higher than the density of water. The temperature exceeds 10 million K (on the Kelvin scale, in terms of degrees Celsius 1 °C = K - 273.1) (Fig. 5).

Above the core, at distances of about 0.2-0.7 solar radii from its center, is radiant energy transfer zone. Energy transfer here is carried out by absorption and emission of photons by individual layers of particles (see Fig. 5).

Rice. 5. Structure of the Sun

Photon(from Greek phos- light), an elementary particle capable of existing only by moving at the speed of light.

Closer to the surface of the Sun, vortex mixing of the plasma occurs, and energy is transferred to the surface

mainly by the movements of the substance itself. This method of energy transfer is called convection, and the layer of the Sun where it occurs is convective zone. The thickness of this layer is approximately 200,000 km.

Above the convective zone is the solar atmosphere, which constantly fluctuates. Both vertical and horizontal waves with lengths of several thousand kilometers propagate here. Oscillations occur with a period of about five minutes.

The inner layer of the Sun's atmosphere is called photosphere. It consists of light bubbles. This granules. Their sizes are small - 1000-2000 km, and the distance between them is 300-600 km. About a million granules can be observed on the Sun at the same time, each of which exists for several minutes. The granules are surrounded by dark spaces. If the substance rises in the granules, then around them it falls. The granules create a general background against which large-scale formations such as faculae, sunspots, prominences, etc. can be observed.

Sunspots- dark areas on the Sun, the temperature of which is lower than the surrounding space.

Solar torches called bright fields surrounding sunspots.

Prominences(from lat. protubero- swell) - dense condensations of relatively cold (compared to the surrounding temperature) substance that rise and are held above the surface of the Sun by a magnetic field. Towards the emergence magnetic field The sun may be driven by the fact that the different layers of the sun rotate with at different speeds: internal parts rotate faster; The core rotates especially quickly.

Prominences, sunspots and faculae are not the only examples solar activity. It also includes magnetic storms and explosions that are called flashes.

Above the photosphere is located chromosphere- the outer shell of the Sun. Origin of the name of this part solar atmosphere due to its reddish color. The thickness of the chromosphere is 10-15 thousand km, and the density of matter is hundreds of thousands of times less than in the photosphere. The temperature in the chromosphere is growing rapidly, reaching tens of thousands of degrees in its upper layers. At the edge of the chromosphere there are observed spicules, representing elongated columns of compacted luminous gas. The temperature of these jets is higher than the temperature of the photosphere. The spicules first rise from the lower chromosphere to 5000-10,000 km, and then fall back, where they fade. All this happens at a speed of about 20,000 m/s. Spi kula lives 5-10 minutes. The number of spicules existing on the Sun at the same time is about a million (Fig. 6).

Rice. 6. The structure of the outer layers of the Sun

Surrounds the chromosphere solar corona- outer layer of the Sun's atmosphere.

The total amount of energy emitted by the Sun is 3.86. 1026 W, and only one two-billionth of this energy is received by the Earth.

Solar radiation includes corpuscular And electromagnetic radiation.Corpuscular fundamental radiation- this is a plasma flow that consists of protons and neutrons, or in other words - solar wind, which reaches near-Earth space and flows around the entire magnetosphere of the Earth. Electromagnetic radiation- This is the radiant energy of the Sun. It reaches in the form of direct and diffuse radiation earth's surface and ensures the thermal regime on our planet.

In the middle of the 19th century. Swiss astronomer Rudolf Wolf(1816-1893) (Fig. 7) calculated a quantitative indicator of solar activity, known throughout the world as the Wolf number. Having processed the observational materials accumulated by the middle of the last century, sun spots, Wolf was able to set the average I-year cycle solar activity. In fact, the time intervals between years of maximum or minimum Wolf numbers range from 7 to 17 years. Simultaneously with the 11-year cycle, a secular, or more precisely 80-90-year, cycle of solar activity occurs. Uncoordinatedly superimposed on each other, they make noticeable changes in the processes taking place in the geographical shell of the Earth.

The close connection of many terrestrial phenomena with solar activity was pointed out back in 1936 by A.L. Chizhevsky (1897-1964) (Fig. 8), who wrote that the overwhelming majority of physical and chemical processes on Earth are the result of the influence of cosmic forces. He was also one of the founders of such science as heliobiology(from Greek helios- sun), studying the influence of the Sun on living matter geographic envelope Earth.

Depending on solar activity, the following occurs: physical phenomena on Earth, such as: magnetic storms, frequency of auroras, amount of ultraviolet radiation, intensity of thunderstorm activity, air temperature, atmospheric pressure, precipitation, level of lakes, rivers, groundwater, salinity and activity of the seas, etc.

The life of plants and animals is associated with the periodic activity of the Sun (there is a correlation between solar cyclicity and the length of the growing season in plants, the reproduction and migration of birds, rodents, etc.), as well as humans (diseases).

Currently, the relationship between solar and earthly processes continue to be studied using artificial Earth satellites.

Terrestrial planets

In addition to the Sun, planets are distinguished as part of the Solar System (Fig. 9).

By size, geographical indicators and chemical composition planets are divided into two groups: terrestrial planets And giant planets. The terrestrial planets include, and. They will be discussed in this subsection.

Rice. 9. Planets of the Solar System

Earth- the third planet from the Sun. A separate subsection will be devoted to it.

Let's summarize. The density of the planet’s substance, and taking into account its size, its mass, depends on the location of the planet in the solar system. How
The closer a planet is to the Sun, the higher its average density of matter. For example, for Mercury it is 5.42 g/cm\ Venus - 5.25, Earth - 5.25, Mars - 3.97 g/cm3.

The general characteristics of the terrestrial planets (Mercury, Venus, Earth, Mars) are primarily: 1) relatively small sizes; 2) high temperatures on the surface and 3) high density of planetary matter. These planets rotate relatively slowly on their axis and have few or no satellites. In the structure of the terrestrial planets, there are four main shells: 1) a dense core; 2) the mantle covering it; 3) bark; 4) light gas-water shell (excluding Mercury). Traces of tectonic activity were found on the surface of these planets.

Giant planets

Now let's get acquainted with the giant planets, which are also part of our solar system. This , .

Giant planets have the following general characteristics: 1) large sizes and mass; 2) quickly rotate around an axis; 3) have rings and many satellites; 4) the atmosphere consists mainly of hydrogen and helium; 5) in the center they have a hot core of metals and silicates.

They are also distinguished by: 1) low surface temperatures; 2) low density of planetary matter.

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” often means 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 was formed in the center, which then turned into a star - the Sun, and a protoplanetary disk of enormous size, from which all the components of the Solar system listed above were subsequently formed. The process, scientists believe, began about 4.6 billion years ago. This hypothesis was called the nebular hypothesis. 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 was introduced into it taking into account knowledge modern sciences. Thus, it is assumed that due to the increase and intensification of collisions of particles with each other, the temperature of the object increased, and after it reached several thousand Kelvin, the protostar acquired a glow. When the temperature 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

Scientists classify our star as a yellow dwarf (G2V) according to its 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 discovered that the Sun contains iron, neon, chromium, calcium, carbon, magnesium, sulfur, silicon, and nitrogen. Thanks to the thermonuclear reaction continuously occurring in its depths, all life on Earth receives the necessary energy. Sunlight- an integral component of photosynthesis, which results in the formation of oxygen. Without sun rays it would be impossible, therefore, an atmosphere suitable for the protein form of life would not be able to form.

Mercury

This is the closest planet to our star. Together with Earth, Venus and Mars, it belongs to the so-called terrestrial planets. Mercury received its name because of its 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 large satellites giant planets, Ganymede and Titan. However, unlike them, Mercury is quite heavy (3.3 x 10 23 kg), and its density is only slightly behind that of Earth. This is due to the presence of a heavy dense core of iron on the planet.

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

Venus

This planet, named after the ancient Greek goddess of love, is more similar to Earth than others in the solar system. physical parameters- weight, density, size, volume. For a long time they were considered twin planets, but over time it became clear that their differences are enormous. So, Venus has no satellites at all. Its atmosphere consists of almost 98% carbon dioxide, and the pressure on the planet’s surface is 92 times higher than Earth’s! Clouds above the surface of the planet, consisting of sulfuric acid vapor, never dissipate, and the temperature here reaches +434 ° C. On the planet they go acid rain, thunderstorms are raging. There is high volcanic activity here. Life, as we understand it, cannot exist on Venus; moreover, descending spacecraft cannot survive in such an atmosphere for long.

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 is brighter than all the stars. The distance to the Sun is 108 million km. It revolves 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, whose representatives are characterized by the presence of a solid surface. Their structure includes a core, mantle and crust (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 the Earth, 71% of whose surface is covered by oceans, Mars is entirely dry land. Water is preserved beneath the planet's surface as a massive ice sheet. Its surface has a reddish tint 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 what 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.

Martian days are slightly longer than Earth ones, and the year is 668.6 days. Unlike Earth, which has one moon, the planet has two satellites irregular shape- Phobos and Deimos. Both of them, like the Moon to the Earth, are constantly turned to Mars with the same side. Phobos is gradually approaching the surface of its planet, moving in a spiral, and will likely fall onto it over time or break into pieces. Deimos, on the contrary, 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

Which planet is the largest? There are four gas giants in the Solar System: Jupiter, Saturn, Uranus and Neptune. Largest sizes Of these, Jupiter has. Its atmosphere, like that of the Sun, consists predominantly of hydrogen. The fifth planet, named after the thunder god, has an average radius of 69,911 km and a mass 318 times that of Earth. The planet's magnetic field is 12 times stronger than the Earth's. Its surface is hidden under opaque clouds. So far, scientists are finding it difficult to say with certainty what processes can occur under this dense veil. It is assumed that there is a boiling hydrogen ocean on the surface of Jupiter. 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 slightly smaller than Jupiter, it is the second largest among the planets. This is the sixth, next planet, also consisting of hydrogen with admixtures of helium, a small amount of ammonia, methane, and water. Hurricanes rage here, the speed of which can reach 1800 km/h! Saturn's magnetic field is not as powerful 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. This is the least dense celestial body in our system.

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

Uranus and Neptune - 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 fourth in mass (14.6 times greater than the Earth's). A year here lasts 84 Earth years, a day lasts 17.5 hours. In the atmosphere of this planet, in addition to hydrogen and helium, methane occupies a significant volume. Therefore, for an earthly observer, Uranus has a soft blue color.

Uranus is the most cold planet Solar system. The temperature of its atmosphere is unique: -224 °C. Why is Uranus more low temperature than on planets that are further from the Sun, scientists do not know.

This planet has 27 satellites. 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's). For a gas giant it is relatively small (only four times more than 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 a layer of frozen gases and water, hidden, in turn, by the atmosphere, a solid rocky core may be hiding.

These two planets are similar in composition, which is why they are sometimes classified as a separate category - ice giants.

Minor planets

Minor planets are celestial bodies that also move around the Sun in their own orbits, but differ from other planets in their small sizes. Previously, only asteroids were classified as such, but more recently, namely since 2006, they also include Pluto, which was previously included in the list of planets of the Solar System and was the last, tenth on it. This is due to changes in terminology. Thus, 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 located 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 “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.

What is known about Pluto is that it consists mainly of ice and rocks. rocks. The main component of its ice sheet is nitrogen. Its poles are covered with eternal snow.

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 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 in 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 the special position of the five brightest planets of the solar system for people seeing 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 large form is called when five celestial bodies line up in one line. Small - when there are only four of them. These phenomena may be visible or invisible from different areas globe. At the same time, a large parade occurs quite rarely - 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, 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 direction opposite to its rotation around the Sun.

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

The four Galilean moons of Jupiter are the largest in the Solar System.

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

Which star system is closest to us? The solar system is closest to star system triple star Alpha Centauri (4.36 light years). It is assumed that planets similar to Earth may exist in it.

About planets for kids

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

You will also need toothpicks to hold our celestial bodies, and as a background you can use a dark sheet of cardboard with small dots painted on it to imitate stars. 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, evolves, but this process, by our standards, is very long. The supply of hydrogen fuel in its depths is huge, but not infinite. So, according to scientists’ hypotheses, 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. The star's luminosity will also increase. It is assumed that in 3.5 billion years, because of this, the climate on Earth will be similar to Venus, 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 high temperatures it will disappear into outer space. Subsequently, according to scientists, the Earth will be absorbed by the Sun and dissolve in its depths.

The outlook is not very bright. However, progress does not stand still, and perhaps by that time new technologies will allow humanity to explore other planets, over which other suns shine. After all, scientists do not yet know how many “solar” systems there are in the world. 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...

> Planets of the Solar System in order

Explore planets of the solar system in order. Photo in high quality, place of the Earth and detailed description each planet around the Sun: from Mercury to Neptune.

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

What is a planet?

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

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

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

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

Planets of the Solar System in order

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

Mercury

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

Now considered the most tiny planet, inferior in size to the satellite Ganymede.

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

Venus

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

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

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

Earth

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

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

Mars

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

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

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

Jupiter

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

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

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

Saturn

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

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

Uranus

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

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

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