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Abstract on the topic: "planetary atmospheres»

Atmosphere of Mercury

The atmosphere of Mercury has an extremely low density. It consists of hydrogen, helium, oxygen, calcium vapor, sodium and potassium. The planet probably receives hydrogen and helium from the Sun, and metals evaporate from its surface. This thin shell can be called "atmosphere" only with a big stretch. The pressure at the surface of the planet is 500 billion times less than at the surface of the Earth (this is less than in modern vacuum installations on Earth).

The maximum surface temperature of Mercury, recorded by sensors, is +410 °C. The average temperature of the night hemisphere is -162 ° C, and the daytime +347 ° C (this is enough to melt lead or tin). Temperature differences due to the change of seasons caused by the elongation of the orbit reach 100 °C on the day side. At a depth of 1 m, the temperature is constant and equal to +75 ° C, because porous soil does not conduct heat well. Organic life on Mercury is ruled out.

Atmosphere of Venus

The atmosphere of Venus is extremely hot and dry. The temperature on the surface reaches its maximum, at about 480 ° C. The atmosphere of Venus contains 105 times more gas than the atmosphere of Earth. The pressure of this atmosphere near the surface is very high, 95 times higher than on Earth. Spaceships have to be designed to withstand the crushing, crushing force of the atmosphere.

In 1970, the first spacecraft to land on Venus could withstand the sweltering heat for only about one hour, just long enough to send back data on surface conditions. Russian aircraft that landed on Venus in 1982 sent color photographs of sharp rocks back to Earth.

Due to the greenhouse effect, Venus is terribly hot. The atmosphere, which is a dense blanket of carbon dioxide, traps the heat that comes from the sun. As a result, a large amount of thermal energy accumulates.

The atmosphere of Venus is divided into several layers. The densest part of the atmosphere, the troposphere, begins on the surface of the planet and extends up to 65 km. The winds near the hot surface are weak, however, in the upper part of the troposphere, the temperature and pressure decrease to terrestrial values, and the wind speed increases to 100 m/s.

Atmospheric pressure on the surface of Venus is 92 times higher than on Earth, and is comparable to the pressure created by a layer of water at a depth of 910 meters. Because of this high pressure, carbon dioxide is no longer actually a gas, but a supercritical fluid. The atmosphere of Venus has a mass of 4.8 1020 kg, which is 93 times the mass of the entire atmosphere of the Earth, and the air density at the surface is 67 kg/m3, i.e. 6.5% of the density of liquid water on Earth.

The troposphere of Venus contains 99% of the entire atmosphere of the planet by mass. 90% of Venus's atmosphere is within 28 km of the surface. At an altitude of 50 km, atmospheric pressure is approximately equal to the pressure on the Earth's surface. On the night side of Venus, clouds can be found even 80 km above the surface.

Upper atmosphere and ionosphere

The mesosphere of Venus lies between 65 and 120 km. Then the thermosphere begins, reaching the upper boundary of the atmosphere (exosphere) at an altitude of 220-350 km.

The mesosphere of Venus can be divided into two levels: lower (62–73 km) and upper (73–95) km. In the first layer, the temperature is almost constant and amounts to 230K (?43°C). This level coincides with the top layer of clouds. At the second level, the temperature begins to decrease, dropping to 165 K (?108 °C) at an altitude of 95 km. It is the coldest place on the day side of Venus's atmosphere. Then the mesopause begins, which is the boundary between the mesosphere and the thermosphere and is located between 95 and 120 km. On the day side of the mesopause, the temperature rises to 300–400 K (27–127 °C)—the values ​​prevailing in the thermosphere. In contrast, the night side of the thermosphere is the coldest place on Venus, with a temperature of 100K (?173°C). It is sometimes called the cryosphere. In 2015, using the Venera Express probe, scientists recorded a thermal anomaly in the altitude range from 90 to 100 kilometers - the average temperatures here are 20-40 degrees higher and equal to 220-224 degrees Kelvin.

Venus has an elongated ionosphere located at an altitude of 120-300 km and almost coinciding with the thermosphere. High levels of ionization persist only on the day side of the planet. On the night side, the electron concentration is almost zero. The ionosphere of Venus consists of three layers: 120-130 km, 140-160 km and 200-250 km. There may also be an additional layer in the region of 180 km. The maximum electron density (the number of electrons per unit volume) of 3 1011 m3 is reached in the second layer near the subsolar point. The upper boundary of the ionosphere - the ionopause - is located at an altitude of 220-375 km. The main ions in the first and second layer are O2+ ions, while the third layer consists of O+ ions. According to observations, the ionospheric plasma is in motion, and solar photoionization on the day side and ion recombination on the night side are the processes mainly responsible for accelerating the plasma to the observed velocities. The plasma flow is apparently sufficient to maintain the observed level of ion concentration on the night side.

Earth's atmosphere

The atmosphere of the planet Earth, one of the geospheres, is a mixture of gases surrounding the Earth, and is contained due to gravity. The atmosphere is primarily composed of nitrogen (N2, 78%) and oxygen (O2, 21%; O3, 10%). The rest (~1%) consists mainly of argon (0.93%) with small impurities of other gases, in particular carbon dioxide (0.03%). In addition, the atmosphere contains about 1.3 h 1.5 h 10 kg of water, the bulk of which is concentrated in the troposphere.

According to changes in temperature with height, the following layers are distinguished in the atmosphere:

· Troposphere- up to 8-10 km in the polar regions and up to 18 km - above the equator. Almost 80% of atmospheric air is concentrated in the troposphere, almost all water vapor, clouds form here and precipitation falls. Heat exchange in the troposphere is predominantly convective. The processes occurring in the troposphere directly affect the life and activities of people. The temperature in the troposphere decreases with height by an average of 6 ° C per 1 km, and the pressure - by 11 mm Hg. in. for every 100 m. The conditional boundary of the troposphere is the tropopause, in which the decrease in temperature with height stops.

· Stratosphere- from the tropopause to the stratopause, which is located at an altitude of about 50-55 km. It is characterized by a slight increase in temperature with height, which reaches a local maximum at the upper boundary. At an altitude of 20-25 km in the stratosphere there is a layer of ozone that protects living organisms from the harmful effects of ultraviolet radiation.

· Mesosphere- located at altitudes of 55-85 km. The temperature gradually drops (from 0 °C in the stratopause to -70 h -90 °C in the mesopause).

· Thermosphere- runs at altitudes from 85 to 400-800 km. The temperature increases with height (from 200 K to 500–2000 K in the turbopause). According to the degree of ionization of the atmosphere, a neutral layer (neutrosphere) is distinguished in it - up to a height of 90 km, and an ionized layer - the ionosphere - above 90 km. By homogeneity, the atmosphere is divided into homosphere (homogeneous atmosphere of constant chemical composition) and heterosphere (the composition of the atmosphere changes with height). The conditional limit between them at an altitude of about 100 km is homopause. The upper part of the atmosphere, where the concentration of molecules decreases so much that they move in predominantly ballistic trajectories, with almost no collisions among themselves, is called the exosphere. It begins at an altitude of about 550 km, consisting mainly of helium and hydrogen, and gradually passes into interplanetary space.

The value of the atmosphere

Although the mass of the atmosphere is only one millionth of the mass of the Earth, it plays a crucial role in various natural cycles (the water cycle, the carbon cycle and the nitrogen cycle). The atmosphere is an industrial source of nitrogen, oxygen and argon, which are obtained by fractional distillation of liquefied air.

Atmosphere of Mars

The atmosphere of Mars was discovered even before the flight of automatic interplanetary stations to the planet. Thanks to the oppositions of the planet, which occur every three years and spectral analysis, astronomers already in the 19th century knew that it has a very homogeneous composition, more than 95% of which is CO2.

In the 20th century, thanks to interplanetary probes, we learned that the atmosphere of Mars and its temperature are strongly interconnected, because due to the transfer of the smallest particles of iron oxide, huge dust storms arise that can cover half of the planet, raising its temperature along the way.

Approximate composition

The gas envelope of the planet consists of 95% carbon dioxide, 3% nitrogen, 1.6% argon, and trace amounts of oxygen, water vapor and other gases. In addition, it is very heavily filled with fine dust particles (mostly iron oxide), which give it a reddish hue. Thanks to the information about the particles of iron oxide, it is not at all difficult to answer the question of what color the atmosphere is.

Why is the red planet's atmosphere made of carbon dioxide? The planet has not had plate tectonics for billions of years. The lack of plate movement allowed volcanic hotspots to spewing magma to the surface for millions of years on end. Carbon dioxide is also a product of an eruption and is the only gas that is constantly replenished by the atmosphere, in fact, this is actually the only reason why it exists. In addition, the planet lost its magnetic field, which contributed to the fact that lighter gases were carried away by the solar wind. Due to continuous eruptions, many large volcanic mountains have appeared. Mount Olympus is the largest mountain in the solar system.

Scientists believe that Mars lost its entire atmosphere due to the fact that it lost its magnetosphere about 4 billion years ago. Once upon a time, the gaseous envelope of the planet was denser and the magnetosphere protected the planet from the solar wind. The solar wind, atmosphere and magnetosphere are strongly interconnected. Solar particles interact with the ionosphere and carry away molecules from it, reducing the density. This is the answer to the question of where the atmosphere has gone. These ionized particles have been detected by spacecraft in the space behind Mars. This results in an average pressure on the surface of 600 Pa, compared to an average pressure on Earth of 101,300 Pa.

Structure

The atmosphere is divided into four main layers: lower, middle, upper and exosphere. The lower layers are a warm region (temperature about 210 K). It is heated by dust in the air (dust 1.5 µm across) and thermal radiation from the surface.

It should be taken into account that, despite the very high rarefaction, the concentration of carbon dioxide in the gaseous envelope of the planet is approximately 23 times greater than in ours. Therefore, the atmosphere of Mars is not so friendly, not only people, but also other terrestrial organisms cannot breathe in it.

Medium - similar to the Earth. The upper layers of the atmosphere are heated by the solar wind and the temperature there is much higher than on the surface. This heat causes the gas to leave the gas envelope. The exosphere begins about 200 km from the surface and does not have a clear boundary. As you can see, the distribution of temperature in height is quite predictable for a terrestrial planet.

Atmosphere of Jupiter

The only visible part of Jupiter is atmospheric clouds and spots. Clouds are located parallel to the equator, depending on the ascending warm or descending cold streams, they are light and dark atmosphere planet mercury earth

In the atmosphere of Jupiter, over 87% by volume of hydrogen and ~ 13% of helium, the rest of the gases, including methane, ammonia, water vapor are in the form of impurities at the level of tenths and hundredths of a percent.

A pressure of 1 atm corresponds to a temperature of 170 K. The tropopause is at a pressure of 0.1 atm and a temperature of 115 K. In the entire underlying high-altitude troposphere, the temperature variation can be characterized by an adiabatic gradient in a hydrogen-helium medium - about 2 K per kilometer. Jupiter's radio emission spectrum also indicates a steady increase in radio brightness temperature with depth. Above the tropopause there is a region of temperature inversion, where the temperature gradually rises to ~180 K up to pressures of the order of 1 mbar. This value is preserved in the mesosphere, which is characterized by almost isotherm to a level with a pressure of ~10-6 atm, and above the thermosphere begins, passing into the exosphere with a temperature of 1250 K.

Clouds of Jupiter

There are three main layers:

1. The topmost, at a pressure of about 0.5 atm, consisting of crystalline ammonia.

2. The intermediate layer is composed of ammonium hydrosulfide

3. The lower layer, at a pressure of several atmospheres, consisting of ordinary water ice.

Some models also assume the existence of the lowest, fourth layer of clouds, consisting of liquid ammonia. On the whole, such a model satisfies the totality of the available experimental data and explains well the color of the zones and belts: the light zones located higher in the atmosphere contain bright white ammonia crystals, and the deeper zones contain red-brown ammonium hydrosulfide crystals.

Like Earth and Venus, lightning has been recorded in Jupiter's atmosphere. Judging by the flashes of light captured in the photographs of Voyager, the intensity of the discharges is extremely high. It is not yet clear, however, to what extent these phenomena are associated with clouds, since the flares were detected at higher altitudes than expected.

Circulation on Jupiter

A characteristic motion on Jupiter is the presence of zonal circulation of tropical and temperate latitudes. The circulation itself is axisymmetric, that is, it has almost no differences at different longitudes. The speeds of eastern and western winds in zones and belts range from 50 to 150 m/s. At the equator, the wind blows eastward at a speed of about 100 m/s.

The structure of zones and belts differs in the nature of vertical movements on which the formation of horizontal currents depends. In light zones, the temperature of which is lower, the movements are ascending, the clouds are denser and located at higher levels in the atmosphere. In the darker (red-brown) belts with higher temperatures, the movements are downward, they are located deeper in the atmosphere and are covered by less dense clouds.

Rings of Jupiter

The rings of Jupiter, surrounding the planet perpendicular to the equator, are located at an altitude of 55,000 km from the atmosphere.

They were discovered by Voyager 1 in March 1979 and have been monitored from Earth ever since. There are two main rings and one very thin inner ring with a characteristic orange color. The thickness of the rings does not seem to exceed 30 km, and the width is 1000 km.

Unlike the rings of Saturn, the rings of Jupiter are dark (albedo (reflectivity) - 0.05). And they probably consist of very small solid particles of a meteoric nature. Particles from Jupiter's rings most likely do not stay in them for long (due to obstacles created by the atmosphere and magnetic field). Therefore, since the rings are permanent, they must be continuously replenished. The small moons of Metis and Adrastea, whose orbits lie within the rings, are obvious sources of such additions. From Earth, Jupiter's rings can only be seen in infrared light.

Atmosphere of Saturn

Saturn's upper atmosphere is made up of 96.3% hydrogen (by volume) and 3.25% helium (compared to 10% in Jupiter's atmosphere). There are impurities of methane, ammonia, phosphine, ethane and some other gases. Ammonia clouds in the upper part of the atmosphere are more powerful than those of Jupiter. Clouds in the lower atmosphere are composed of ammonium hydrosulfide (NH4SH) or water.

According to the Voyagers, strong winds blow on Saturn, the devices recorded air speeds of 500 m / s. The winds blow mainly in an easterly direction (in the direction of axial rotation). Their strength weakens with distance from the equator; as we move away from the equator, westerly atmospheric currents also appear. A number of data indicate that the circulation of the atmosphere occurs not only in the upper cloud layer, but also at a depth of at least 2,000 km. In addition, Voyager 2 measurements showed that the winds in the southern and northern hemispheres are symmetrical about the equator. There is an assumption that symmetrical flows are somehow connected under the layer of the visible atmosphere.

In the atmosphere of Saturn, stable formations sometimes appear, which are super-powerful hurricanes. Similar objects are observed on other gas planets of the solar system (see the Great Red Spot on Jupiter, the Great Dark Spot on Neptune). The giant "Great White Oval" appears on Saturn about once every 30 years, the last time it was observed in 1990 (smaller hurricanes form more often).

On November 12, 2008, Cassini's cameras took infrared images of Saturn's north pole. On them, the researchers found auroras, the likes of which have never been observed in the solar system. Also, these auroras were observed in the ultraviolet and visible ranges. Auroras are bright continuous oval rings surrounding the planet's pole. The rings are located at a latitude, as a rule, at 70--80 °. The southern rings are located at an average latitude of 75 ± 1°, while the northern ones are approximately 1.5° closer to the pole, which is due to the fact that the magnetic field is somewhat stronger in the northern hemisphere. Sometimes the rings become spiral instead of oval.

Unlike Jupiter, Saturn's auroras are not related to the uneven rotation of the plasma sheet in the outer parts of the planet's magnetosphere. Presumably, they arise due to magnetic reconnection under the influence of the solar wind. The shape and appearance of Saturn's auroras change greatly over time. Their location and brightness are strongly related to the pressure of the solar wind: the greater it is, the brighter the aurora and closer to the pole. The average power of the aurora is 50 GW in the range of 80–170 nm (ultraviolet) and 150–300 GW in the range of 3–4 µm (infrared).

During storms and storms, powerful lightning discharges are observed on Saturn. The electromagnetic activity of Saturn caused by them fluctuates over the years from almost complete absence to very strong electrical storms.

On December 28, 2010, Cassini photographed a storm resembling cigarette smoke. Another, especially powerful storm, was recorded on May 20, 2011.

Atmosphere of Uranus

The atmosphere of Uranus, like the atmospheres of Jupiter and Saturn, consists mainly of hydrogen and helium. At great depths, it contains significant amounts of water, ammonia and methane, which is a hallmark of the atmospheres of Uranus and Neptune. The opposite picture is observed in the upper atmosphere, which contains very few substances heavier than hydrogen and helium. The atmosphere of Uranus is the coldest of all planetary atmospheres in the solar system, with a minimum temperature of 49 K.

The atmosphere of Uranus can be divided into three main layers:

1. Troposphere- occupies an altitude range from? 300 km to 50 km (0 is taken as a conditional boundary, where the pressure is 1 bar;) and a pressure range from 100 to 0.1 bar

2. Stratosphere-- covers altitudes from 50 to 4000 km and pressures between 0.1 and 10?10 bar

3. Exosphere-- extends from a height of 4000 km to several radii of the planet, the pressure in this layer tends to zero with distance from the planet.

It is noteworthy that, unlike Earth, the atmosphere of Uranus does not have a mesosphere.

There are four cloud layers in the troposphere: methane clouds at the boundary corresponding to a pressure of about 1.2 bar; hydrogen sulfide and ammonia clouds in the pressure layer of 3-10 bar; clouds of ammonium hydrosulfide at 20-40 bar, and, finally, water clouds of ice crystals below the conditional pressure limit of 50 bar. Only the two upper cloud layers are accessible to direct observation, while the existence of the underlying layers is predicted only theoretically. Bright tropospheric clouds are rarely observed on Uranus, which is probably due to the low convection activity in the deep regions of the planet. However, observations of such clouds have been used to measure the speed of zonal winds on the planet, which goes up to 250 m/s.

There is currently less information about the atmosphere of Uranus than about the atmospheres of Saturn and Jupiter. As of May 2013, only one spacecraft, Voyager 2, has studied Uranus at close range. No other missions to Uranus are currently planned.

Atmosphere of Neptune

In the upper layers of the atmosphere, hydrogen and helium were found, which account for 80 and 19%, respectively, at a given altitude. There are also traces of methane. Noticeable methane absorption bands occur at wavelengths above 600 nm in the red and infrared parts of the spectrum. As with Uranus, the absorption of red light by methane is a major factor in giving Neptune's atmosphere a blue tint, although Neptune's bright azure differs from Uranus's more moderate aquamarine. Since the methane content in Neptune's atmosphere is not much different from that of Uranus, it is assumed that there is also some, as yet unknown, component of the atmosphere that contributes to the formation of blue. The atmosphere of Neptune is divided into 2 main regions: the lower troposphere, where the temperature decreases with height, and the stratosphere, where the temperature, on the contrary, increases with height. The boundary between them, the tropopause, is at a pressure level of 0.1 bar. The stratosphere is replaced by the thermosphere at a pressure level lower than 10?4 -- 10?5 microbars. The thermosphere gradually passes into the exosphere. Models of Neptune's troposphere suggest that, depending on height, it consists of clouds of variable composition. The upper level clouds are in the pressure zone below one bar, where the temperature favors the condensation of methane.

At pressures between one and five bar, clouds of ammonia and hydrogen sulfide form. At pressures above 5 bar, the clouds may consist of ammonia, ammonium sulfide, hydrogen sulfide and water. Deeper, at a pressure of approximately 50 bar, clouds of water ice can exist at a temperature of 0 °C. Also, it is possible that clouds of ammonia and hydrogen sulfide can be found in this zone. High-altitude clouds of Neptune were observed by the shadows they cast on the opaque cloud layer below the level. Among them, cloud bands stand out, which “wrap” around the planet at a constant latitude. These peripheral groups have a width of 50-150 km, and they themselves are 50-110 km above the main cloud layer. A study of Neptune's spectrum suggests that its lower stratosphere is hazy due to the condensation of ultraviolet photolysis products of methane, such as ethane and acetylene. Traces of hydrogen cyanide and carbon monoxide have also been found in the stratosphere. The stratosphere of Neptune is warmer than the stratosphere of Uranus due to the higher concentration of hydrocarbons. For unknown reasons, the planet's thermosphere has an abnormally high temperature of about 750 K. For such a high temperature, the planet is too far from the Sun for it to heat up the thermosphere with ultraviolet radiation. Perhaps this phenomenon is a consequence of atmospheric interaction with ions in the planet's magnetic field. According to another theory, the basis of the heating mechanism is gravity waves from the inner regions of the planet, which are scattered in the atmosphere. The thermosphere contains traces of carbon monoxide and water, which may have come from outside sources such as meteorites and dust.

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Astrologer, you also need to copy-paste wisely and indicate the source ...))) Although, it seems that the question was intended for you ... well, it won’t get away from me. Mercury has practically no atmosphere - only an extremely rarefied helium shell with the density of the earth's atmosphere at an altitude of 200 km. Probably, helium is formed during the decay of radioactive elements in the bowels of the planet. In addition, it is made up of atoms captured from the solar wind or knocked out by the solar wind from the surface - sodium, oxygen, potassium, argon, hydrogen. The atmosphere of Venus is composed primarily of carbon dioxide (CO2) with small amounts of nitrogen (N2) and water vapor (H2O). Hydrochloric acid (HCl) and hydrofluoric acid (HF) were found as small impurities. The pressure at the surface is 90 bar (as in the Earth's seas at a depth of 900 m). The clouds of Venus are made up of microscopic droplets of concentrated sulfuric acid (H2SO4). The rarefied atmosphere of Mars consists of 95% carbon dioxide and 3% nitrogen. Small amounts of water vapor, oxygen and argon are present. The average pressure at the surface is 6 mbar (i.e., 0.6% of the earth). Jupiter's low mean density (1.3 g/cm3) indicates a composition close to the Sun's: mostly hydrogen and helium. A telescope on Jupiter shows cloud bands parallel to the equator; light zones in them are interspersed with reddish belts. It is likely that the light zones are areas of updrafts where the tops of ammonia clouds are visible; reddish belts are associated with downdrafts, the bright color of which is determined by ammonium hydrosulfate, as well as compounds of red phosphorus, sulfur and organic polymers. In addition to hydrogen and helium, CH4, NH3, H2O, C2H2, C2H6, HCN, CO, CO2, PH3, and GeH4 have been spectroscopically detected in Jupiter's atmosphere. At a depth of 60 km there should be a layer of water clouds. Its satellite Io has an extremely rarefied atmosphere of sulfur dioxide (of volcanic origin) SO2. The oxygen atmosphere of Europe is so rarefied that the pressure on the surface is one hundred billionth of that of the earth. Saturn is also a hydrogen-helium planet, but the relative abundance of helium in Saturn is less than that of Jupiter; below and its average density. Its upper atmosphere is filled with light-scattering ammonia (NH3) fog. In addition to hydrogen and helium, CH4, C2H2, C2H6, C3H4, C3H8, and PH3 have been spectroscopically detected in Saturn's atmosphere. Titan, the second largest moon in the solar system, is unique in that it has a persistent, powerful atmosphere composed mostly of nitrogen and a small amount of methane. The atmosphere of Uranus contains mostly hydrogen, 12–15% helium, and a few other gases. The spectrum of Neptune is also dominated by methane and hydrogen bands. Pluto hasn't been a planet for a long time... And as a bonus.

What can be the connection between the presence of the atmosphere on the planet and the duration of its revolution around the axis? It would seem that none. And yet, on the example of the planet closest to the Sun, Mercury, we are convinced that in some cases such a connection exists.

In terms of gravity on its surface, Mercury could hold an atmosphere of the same composition as Earth's, although not as dense.

The speed required to completely overcome the attraction of Mercury on its surface is 4900 m / s, and this speed at low temperatures is not reached by the fastest of the molecules of our atmosphere). And yet Mercury has no atmosphere. The reason is that it moves around the Sun like the movement of the Moon around the Earth, that is, it always faces the central luminary with the same side. The time to go around the orbit (88 days) is equal to the time of revolution around the axis. Therefore, on one side of Mercury - that which is always turned towards the Sun - there is an uninterrupted day and eternal summer; on the other side, turned away from the Sun, uninterrupted night and eternal winter reign.

Under such extraordinary climatic conditions, what should happen to the planet's atmosphere? Obviously, in the night half, under the influence of a terrible cold, the atmosphere will thicken into a liquid and freeze. As a result of a sharp decrease in atmospheric pressure, the gaseous envelope of the day side of the planet will rush there and solidify in turn. As a result, the entire atmosphere should collect in solid form on the night side of the planet, or rather, in that part of it where the Sun does not look at all. Thus, the absence of an atmosphere on Mercury is an inevitable consequence of physical laws.

For the same reasons that the existence of an atmosphere on Mercury is inadmissible, we must also reject the conjecture, often expressed, that there is an atmosphere on the invisible side of the Moon. It is safe to say that if there is no atmosphere on one side of the Moon, then it cannot be on the opposite side either). Wells' fantastic novel The First Men in the Moon diverges from the truth on this point. The novelist admits that there is air on the Moon, which, during a continuous 14-day night, manages to thicken and freeze, and with the onset of day, it again turns into a gaseous state, forming an atmosphere. Nothing of the kind, however, can happen. “If,” wrote Prof. O. D. Khvolson, - on the dark side of the Moon, the air solidifies, then almost all the air should pass from the light side to the dark side and freeze there as well. Under the influence of the sun's rays, solid air must turn into a gas, which will immediately pass to the dark side and solidify there ... There must be a continuous distillation of air, and nowhere and never can it achieve any noticeable elasticity.

It has even been established that in the atmosphere, more precisely, in the stratosphere of Venus, there is a lot of carbon dioxide - ten thousand times more than in the earth's atmosphere.

4.6 billion years ago, clumps began to form in our Galaxy from clouds of stellar matter. Increasingly, more compacted and thickened, the gases heated up, radiating heat. With increasing density and temperature, nuclear reactions began, turning hydrogen into helium. Thus, there was a very powerful source of energy - the Sun.

Simultaneously with the increase in the temperature and volume of the Sun, as a result of the union of fragments of interstellar dust in a plane perpendicular to the axis of rotation of the Star, planets and their satellites were created. The formation of the solar system was completed about 4 billion years ago.

The solar system currently has eight planets. These are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Nepto. Pluto is a dwarf planet, the largest known Kuiper belt object (it is a large fragment belt similar to the asteroid belt). After its discovery in 1930, it was considered the ninth planet. The situation changed in 2006 with the adoption of a formal definition of the planet.

On the planet closest to the Sun, Mercury, it never rains. This is due to the fact that the atmosphere of the planet is so rarefied that it is simply impossible to fix it. And where can rain come from, if the daytime temperature on the surface of the planet sometimes reaches 430º Celsius. Yeah, I wouldn't want to be there :)

But on Venus, acid rains constantly occur, since the clouds above this planet do not consist of life-giving water, but of deadly sulfuric acid. True, since the temperature on the surface of the third planet reaches 480º Celsius, the drops of acid evaporate before they reach the planet. The sky above Venus is pierced by large and terrible lightning, but there is more light and roar from them than rain.

On Mars, according to scientists, a long time ago, natural conditions were the same as on Earth. Billions of years ago, the atmosphere above the planet was much denser, and it is possible that abundant rains filled these rivers. But now the planet has a very rarefied atmosphere, and photographs transmitted by reconnaissance satellites indicate that the surface of the planet resembles the deserts of the southwestern United States or the Dry Valleys in Antarctica. When part of Mars is shrouded in winter, thin clouds containing carbon dioxide appear over the red planet, and frost covers dead rocks. In the early morning in the valleys there are such thick fogs that it seems that it is about to rain, but such expectations are in vain.

By the way, the air temperature during the day on Mrse is 20º Celsius. True, at night it can drop to -140 :(

Jupiter is the largest of the planets and is a giant ball of gas! This ball is composed almost entirely of helium and hydrogen, but it is possible that deep inside the planet is a small solid core, shrouded in an ocean of liquid hydrogen. However, Jupiter is surrounded on all sides by colored bands of clouds. Some of these clouds even consist of water, but, as a rule, the vast majority of them form solidified ammonia crystals. From time to time, the strongest hurricanes and storms fly over the planet, bringing snowfalls and rains of ammonia. That's where to hold the Magic Flower.

The article talks about which planet does not have an atmosphere, why an atmosphere is needed, how it arises, why some are deprived of it, and how it could be created artificially.

Start

Life on our planet would be impossible without an atmosphere. And the point is not only in the oxygen that we breathe, by the way, it contains only a little more than 20%, but also in the fact that it creates the pressure necessary for living beings and protects from solar radiation.

According to the scientific definition, the atmosphere is the gaseous shell of the planet that rotates with it. To put it simply, a huge accumulation of gas is constantly hanging above us, but we will not notice its weight in the same way as the Earth's gravity, because we were born in such conditions and got used to it. But not all celestial bodies are lucky to have it. So which planet does not take into account we will not take into account, since it is still a satellite.

Mercury

The atmosphere of planets of this type consists mainly of hydrogen, and the processes in it are very violent. What is worth only one atmospheric vortex, which has been observed for more than three hundred years - that same red spot in the lower part of the planet.

Saturn

Like all gas giants, Saturn is made up mostly of hydrogen. Winds do not subside on it, lightning sparkles and even rare auroras are observed.

Uranus and Neptune

Both planets are hidden by a thick layer of clouds of hydrogen, methane and helium. Neptune, by the way, holds the record for wind speed on the surface - as much as 700 kilometers per hour!

Pluto

Remembering such a phenomenon as a planet without an atmosphere, it is difficult not to mention Pluto. Of course, it is far from Mercury: its gaseous shell is "only" 7 thousand times less dense than the earth's. But still it is the most distant and so far little-studied planet. Little is also known about it - only that methane is present in it.

How to create an atmosphere for life

The idea of ​​colonizing other planets haunts scientists from the very beginning And even more so about terraformation (creation on conditions without means of protection). All this is still at the level of hypotheses, but on the same Mars it is quite possible to create an atmosphere. This process is complex and multi-stage, but its main idea is as follows: to spray bacteria on the surface, which will produce even more carbon dioxide, the density of the gas shell will increase, and the temperature will rise. After that, the melting of the polar glaciers will begin, and due to the increase in pressure, the water will not evaporate without a trace. And then the rains will come, and the soil will become suitable for plants.

So we figured out which planet is practically devoid of an atmosphere.