Predominant in the atmosphere of Mars. The atmosphere of Mars - the chemical composition, weather conditions and climate in the past. On the movement of Mars

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The study

The atmosphere of Mars was discovered even before the flights of automatic interplanetary stations to the planet. Thanks to spectral analysis and the oppositions of Mars with the Earth, which happen once every 3 years, astronomers already in the 19th century knew that it has a very homogeneous composition, more than 95% of which is carbon dioxide. Compared to 0.04% carbon dioxide in the Earth's atmosphere, it turns out that the mass of Martian atmospheric carbon dioxide exceeds the mass of the Earth's by almost 12 times, so that during the terraforming of Mars, the carbon dioxide contribution to the greenhouse effect can create a climate comfortable for humans somewhat earlier than a pressure of 1 atmosphere is reached, even taking into account the greater distance of Mars from the Sun.

Back in the early 1920s, the first measurements of the temperature of Mars were made using a thermometer placed at the focus of a reflecting telescope. Measurements by V. Lampland in 1922 gave an average surface temperature of Mars of 245 (−28 °C), E. Pettit and S. Nicholson in 1924 obtained 260 K (−13 °C). A lower value was obtained in 1960 by W. Sinton and J. Strong: 230 K (−43 ° C). The first estimates of pressure - averaged - were obtained only in the 60s using ground-based IR spectroscopes: a pressure of 25 ± 15 hPa obtained from the Lorentz broadening of carbon dioxide lines meant that it was the main component of the atmosphere.

The wind speed can be determined from the Doppler shift of the spectral lines. So, for this, the line shift was measured in the millimeter and submillimeter range, and measurements on the interferometer make it possible to obtain the distribution of velocities in the whole layer of great thickness.

The most detailed and accurate data on air and surface temperature, pressure, relative humidity and wind speed are continuously measured by the Rover Environmental Monitoring Station (REMS) instrumentation aboard the Curiosity rover, which has been operating in the Gale crater since 2012. And the MAVEN spacecraft, which has been orbiting Mars since 2014, is specifically designed to study the upper atmosphere in detail, their interaction with solar wind particles, and in particular the scattering dynamics.

A number of processes that are difficult or not yet possible for direct observation are subject only to theoretical modeling, but it is also important method research.

Atmospheric structure

In general, the atmosphere of Mars is divided into lower and upper; the latter is considered to be the region above 80 km above the surface, where the processes of ionization and dissociation play an active role. A section is devoted to its study, which is commonly called aeronomy. Usually, when people talk about the atmosphere of Mars, they mean the lower atmosphere.

Also, some researchers distinguish two large shells - the homosphere and the heterosphere. In the homosphere chemical composition does not depend on altitude, since the processes of heat and moisture transfer in the atmosphere and their vertical exchange are entirely determined by turbulent mixing. Since molecular diffusion in the atmosphere is inversely proportional to its density, then from a certain level this process becomes predominant and is the main feature of the upper shell - the heterosphere, where molecular diffuse separation occurs. The interface between these shells, which is located at altitudes from 120 to 140 km, is called the turbopause.

lower atmosphere

From the surface to a height of 20-30 km stretches troposphere where the temperature decreases with height. The upper limit of the troposphere varies depending on the time of year (the temperature gradient in the tropopause varies from 1 to 3 deg/km, with an average value of 2.5 deg/km).

Above the tropopause is an isothermal region of the atmosphere - stratomesosphere stretching up to a height of 100 km. The average temperature of the stratomesosphere is exceptionally low and amounts to -133°C. Unlike the Earth, where the stratosphere contains predominantly all atmospheric ozone, on Mars its concentration is negligible (it is distributed from altitudes of 50 - 60 km to the very surface, where it is maximum).

upper atmosphere

Above the stratomesosphere extends the upper layer of the atmosphere - thermosphere. It is characterized by an increase in temperature with height up to a maximum value (200-350 K), after which it remains constant up to the upper limit (200 km). The presence of atomic oxygen was registered in this layer; its density at a height of 200 km reaches 5-6⋅10 7 cm −3 . The presence of a layer dominated by atomic oxygen (as well as the fact that the main neutral component is carbon dioxide) combines the atmosphere of Mars with the atmosphere of Venus.

Ionosphere- a region with a high degree of ionization - is located in the altitude range from about 80-100 to about 500-600 km. The content of ions is minimal at night and maximal during the day, when the main layer is formed at an altitude of 120-140 km due to the photoionization of carbon dioxide extreme ultraviolet solar radiation CO 2 + hν → CO 2 + + e -, as well as reactions between ions and neutral substances CO 2 + + O → O 2 + + CO and O + + CO 2 → O 2 + + CO. The concentration of ions, of which 90% O 2 + and 10% CO 2 +, reaches 10 5 per cubic centimeter (in other areas of the ionosphere it is 1-2 orders of magnitude lower). It is noteworthy that O 2 + ions predominate in the almost complete absence of molecular oxygen proper in the Martian atmosphere. The secondary layer is formed in the region of 110-115 km due to soft X-rays and knocked out fast electrons. At an altitude of 80-100 km, some researchers distinguish a third layer, sometimes manifested under the influence of particles space dust, bringing metal ions Fe + , Mg + , Na + into the atmosphere. However, later it was not only confirmed the appearance of the latter (moreover, over almost the entire volume of the upper atmosphere) due to the ablation of the substance of meteorites and other cosmic bodies entering the atmosphere of Mars, but also their constant presence in general. At the same time, due to the absence of Mars magnetic field their distribution and behavior differ significantly from what is observed in the earth's atmosphere. Above the main maximum, other additional layers can also appear due to interaction with the solar wind. Thus, the layer of O+ ions is most pronounced at an altitude of 225 km. In addition to the three main types of ions (O 2 +, CO 2 and O +), relatively recently H 2 + , H 3 + , He + , C + , CH + , N + , NH + , OH + , H 2 O + , H 3 O + , N 2 + /CO + , HCO + /HOC + /N 2 H + , NO + , HNO + , HO 2 + , Ar + , ArH + , Ne + , CO 2 ++ and HCO2+. Above 400 km, some authors distinguish an "ionopause", but there is no consensus on this yet.

As for the plasma temperature, the ion temperature near the main maximum is 150 K, increasing to 210 K at an altitude of 175 km. Higher, the thermodynamic equilibrium of ions with a neutral gas is significantly disturbed, and their temperature rises sharply to 1000 K at an altitude of 250 km. The temperature of electrons can be several thousand kelvins, apparently due to the magnetic field in the ionosphere, and it grows with increasing solar zenith angle and is not the same in the northern and southern hemispheres, which may be due to the asymmetry of the residual magnetic field of the Martian crust. In general, one can even distinguish three populations of high-energy electrons with different temperature profiles. The magnetic field also affects the horizontal distribution of ions: streams of high-energy particles are formed above magnetic anomalies, swirling along the field lines, which increases the ionization intensity, and an increased ion density and local structures are observed.

At an altitude of 200-230 km, there is the upper boundary of the thermosphere - the exobase, above which the exosphere Mars. It consists of light substances - hydrogen, carbon, oxygen - which appear as a result of photochemical reactions in the underlying ionosphere, for example, dissociative recombination of O 2 + with electrons. The continuous supply of atomic hydrogen to the upper atmosphere of Mars occurs due to the photodissociation of water vapor near the Martian surface. Due to the very slow decrease in hydrogen concentration with height, this element is the main component of the outermost layers of the planet's atmosphere and forms a hydrogen corona that extends over a distance of about 20,000 km, although there is no strict boundary, and particles from this region simply gradually dissipate into the surrounding outer space.

In the atmosphere of Mars, it is also sometimes released chemosphere- the layer where photochemical reactions take place, and since, due to the lack of an ozone screen, like that of the Earth, ultraviolet radiation reaches the very surface of the planet, they are possible even there. The Martian chemosphere extends from the surface to an altitude of about 120 km.

Chemical composition of the lower atmosphere

Despite the strong rarefaction of the Martian atmosphere, the concentration of carbon dioxide in it is about 23 times greater than in the earth.

  • Nitrogen (2.7%) is currently actively dissipating into space. In the form of a diatomic molecule, nitrogen is stably held by the attraction of the planet, but is split by solar radiation into single atoms, easily leaving the atmosphere.
  • Argon (1.6%) is represented by the relatively dissipation-resistant heavy isotope argon-40. Light 36 Ar and 38 Ar are present only in parts per million
  • Other noble gases: neon, krypton, xenon (ppm)
  • Carbon monoxide (CO) - is a product of CO 2 photodissociation and is 7.5⋅10 -4 concentration of the latter - this is an inexplicably small value, since the reverse reaction CO + O + M → CO 2 + M is prohibited, and much more should have accumulated CO. Various theories have been proposed for how carbon monoxide can still be oxidized to carbon dioxide, but they all have one or another drawback.
  • Molecular oxygen (O 2) - appears as a result of photodissociation of both CO 2 and H 2 O in the upper atmosphere of Mars. In this case, oxygen diffuses into the lower layers of the atmosphere, where its concentration reaches 1.3⋅10 -3 of the near-surface concentration of CO 2 . Like Ar, CO, and N 2 , it is a non-condensable substance on Mars, so its concentration also undergoes seasonal variations. In the upper atmosphere, at a height of 90-130 km, the content of O 2 (share relative to CO 2) is 3-4 times higher than the corresponding value for the lower atmosphere and averages 4⋅10 -3 , varying in the range from 3.1⋅10 -3 to 5.8⋅10 -3 . In ancient times, the atmosphere of Mars contained, however, a larger amount of oxygen, comparable to its share on the young Earth. Oxygen, even in the form of individual atoms, no longer dissipates as actively as nitrogen, due to its greater atomic weight, which allows it to accumulate.
  • Ozone - its amount varies greatly depending on surface temperature: it is minimum at the time of the equinox at all latitudes and maximum at the pole, where winter is, moreover, inversely proportional to the concentration of water vapor. There is one pronounced ozone layer at an altitude of about 30 km and another between 30 and 60 km.
  • Water. The content of H 2 O in the atmosphere of Mars is about 100-200 times less than in the atmosphere of the driest regions of the Earth, and averages 10-20 microns of a precipitated water column. Water vapor concentration undergoes significant seasonal and diurnal variations. The degree of air saturation with water vapor is inversely proportional to the content of dust particles, which are centers of condensation, and in some areas (in winter, at an altitude of 20-50 km), steam was recorded, the pressure of which exceeds the saturated vapor pressure by 10 times - much more than in the earth's atmosphere .
  • Methane. Since 2003, there have been reports of registration of methane emissions of an unknown nature, but none of them can be considered reliable due to certain shortcomings in the registration methods. In this case, we are talking about extremely small values ​​- 0.7 ppbv (upper limit - 1.3 ppbv) as a background value and 7 ppbv for episodic bursts, which is on the verge of resolution. Since, along with this, information was also published about the absence of CH 4 confirmed by other studies, this may indicate some kind of intermittent source of methane, as well as the existence of some mechanism for its rapid destruction, while the duration of the photochemical destruction of this substance is estimated at 300 years. The discussion on this issue is currently open, and it is of particular interest in the context of astrobiology, in view of the fact that on Earth this substance has a biogenic origin.
  • traces of some organic compounds. The most important are the upper limits on H 2 CO, HCl and SO 2, which indicate the absence, respectively, of reactions involving chlorine, as well as volcanic activity, in particular, the non-volcanic origin of methane, if its existence is confirmed.

The composition and pressure of the atmosphere of Mars make it impossible for humans and other terrestrial organisms to breathe. To work on the surface of the planet, a spacesuit is necessary, although not as bulky and protected as for the Moon and open space. The atmosphere of Mars itself is not poisonous and consists of chemically inert gases. The atmosphere somewhat slows down meteorite bodies, so there are fewer craters on Mars than on the Moon and they are less deep. And micrometeorites burn out completely, not reaching the surface.

Water, clouds and precipitation

low density does not prevent the atmosphere from forming large-scale phenomena that affect the climate.

Water vapor in the Martian atmosphere is no more than a thousandth of a percent, however, according to the results of recent (2013) studies, this is still more than previously thought, and more than in the upper layers of the Earth's atmosphere, and at low pressure and temperature, it is in a state close to saturation, so it often gathers in clouds. As a rule, water clouds form at altitudes of 10-30 km above the surface. They are concentrated mainly on the equator and are observed almost throughout the year. Clouds seen on high levels atmosphere (more than 20 km) are formed as a result of CO 2 condensation. The same process is responsible for the formation of low (at an altitude of less than 10 km) clouds in the polar regions in winter, when the atmospheric temperature drops below the freezing point of CO 2 (-126 ° C); in summer, similar thin formations are formed from ice H 2 O

  • One of the interesting and rare atmospheric phenomena on Mars was discovered ("Viking-1") when photographing the northern polar region in 1978. These are cyclonic structures that are clearly identified in photographs by vortex-like cloud systems with counterclockwise circulation. They were found in the latitudinal zone 65-80°N. sh. during the "warm" period of the year, from spring to early autumn, when the polar front is established here. Its occurrence is due to the sharp contrast in surface temperatures at this time of year between the edge of the ice cap and the surrounding plains. The wave movements of air masses associated with such a front lead to the appearance of cyclonic eddies so familiar to us on Earth. The systems of vortex clouds found on Mars vary in size from 200 to 500 km, their speed of movement is about 5 km/h, and the wind speed at the periphery of these systems is about 20 m/s. The duration of existence of an individual cyclonic eddy ranges from 3 to 6 days. The temperature values ​​in the central part of the Martian cyclones indicate that the clouds are composed of water ice crystals.

    Snow has indeed been observed more than once. So, in the winter of 1979, a thin layer of snow fell in the Viking-2 landing area, which lay for several months.

    Dust storms and dust devils

    A characteristic feature of the atmosphere of Mars is the constant presence of dust; according to spectral measurements, the size of dust particles is estimated at 1.5 µm. Low gravity allows even rarefied air flows to raise huge clouds of dust to a height of up to 50 km. And the winds, which are one of the manifestations of the temperature difference, often blow over the surface of the planet (especially in late spring - early summer in the southern hemisphere, when the temperature difference between the hemispheres is especially sharp), and their speed reaches 100 m / s. Thus, vast dust storms are formed, which have long been observed in the form of individual yellow clouds, and sometimes in the form of a continuous yellow veil covering the entire planet. Most often, dust storms occur near the polar caps, their duration can reach 50-100 days. Weak yellow haze in the atmosphere, as a rule, is observed after large dust storms and is easily detected by photometric and polarimetric methods.

    Dust storms, which were well observed on images taken from orbiters, turned out to be barely visible when photographed from landers. The passage of dust storms in the landing sites of these space stations was recorded only by a sharp change in temperature, pressure and a very slight darkening of the general sky background. The layer of dust that settled after the storm in the vicinity of the Viking landing sites amounted to only a few micrometers. All this indicates a rather low bearing capacity of the Martian atmosphere.

    From September 1971 to January 1972, a global dust storm took place on Mars, which even prevented photographing the surface from the Mariner 9 probe. The mass of dust in the atmospheric column (with an optical thickness of 0.1 to 10) estimated during this period ranged from 7.8⋅10 -5 to 1.66⋅10 -3 g/cm 2 . Thus, the total weight of dust particles in the Martian atmosphere during the period of global dust storms can reach up to 10 8 - 10 9 tons, which is commensurate with the total amount of dust in the Earth's atmosphere.

    • The aurora was first recorded by the SPICAM UV spectrometer aboard the Mars Express spacecraft. Then it was repeatedly observed by the MAVEN apparatus, for example, in March 2015, and in September 2017, a much more powerful event was recorded by the Radiation Assessment Detector (RAD) on the Curiosity rover. An analysis of the data from the MAVEN apparatus also revealed aurora of a fundamentally different type - diffuse, which occur at low latitudes, in areas that are not tied to magnetic field anomalies and are caused by the penetration of particles with very high energy, about 200 keV, into the atmosphere.

      In addition, the extreme ultraviolet radiation of the Sun causes the so-called own  glow of the atmosphere (eng. airglow).

      The registration of optical transitions during auroras and intrinsic glow provides important information about the composition of the upper atmosphere, its temperature, and dynamics. Thus, the study of the γ- and δ-bands of nitric oxide emission during the night period helps to characterize the circulation between the illuminated and unilluminated regions. And registration of radiation at a frequency of 130.4 nm with its own glow helped to reveal the presence of high-temperature atomic oxygen, which was an important step in understanding the behavior of atmospheric exospheres and coronas in general.

      Color

      The dust particles that fill the Martian atmosphere are mostly iron oxide, and it gives it a reddish-orange tint.

      According to measurements, the atmosphere has an optical thickness of 0.9, which means that only 40% of the incident solar radiation reaches the surface of Mars through its atmosphere, and the remaining 60% is absorbed by dust hanging in the air. Without it, the Martian skies would have approximately the same color as the earth's sky at an altitude of 35 kilometers. It should be noted that in this case the human eye would adapt to these colors, and the white balance would automatically be adjusted so that the sky would be seen the same as under terrestrial lighting conditions.

      The color of the sky is very heterogeneous, and in the absence of clouds or dust storms from a relatively light on the horizon, it darkens sharply and in a gradient towards the zenith. In a relatively calm and windless season, when there is less dust, the sky can be completely black at the zenith.

      Nevertheless, thanks to the images of the rovers, it became known that at sunset and sunrise around the Sun, the sky turns blue. The reason for this is Rayleigh scattering - light scatters on gas particles and colors the sky, but if on a Martian day the effect is weak and invisible to the naked eye due to rarefied atmosphere and dust, then at sunset the sun shines through a much thicker layer of air, due to which blue and violet begin to scatter components. The same mechanism is responsible for the blue sky on Earth during the day and yellow-orange at sunset. [ ]

      A panorama of the Rocknest sand dunes, compiled from images from the Curiosity rover.

      Changes

      Changes in the upper layers of the atmosphere are quite complex, since they are connected with each other and with the underlying layers. Atmospheric waves and tides propagating upwards can have a significant effect on the structure and dynamics of the thermosphere and, as a consequence, the ionosphere, for example, the height of the upper boundary of the ionosphere. During dust storms in the lower atmosphere, its transparency decreases, it heats up and expands. Then the density of the thermosphere increases - it can vary even by an order of magnitude - and the height of the electron concentration maximum can rise by up to 30 km. Changes in the upper atmosphere caused by dust storms can be global, affecting areas up to 160 km above the planet's surface. The response of the upper atmosphere to these phenomena takes several days, and it returns to its previous state much longer - several months. Another manifestation of the relationship between the upper and lower atmosphere is that water vapor, which, as it turned out, is oversaturated with the lower atmosphere, can undergo photodissociation into lighter H and O components, which increase the density of the exosphere and the intensity of water loss by the Martian atmosphere. External factors causing changes in the upper atmosphere are extreme ultraviolet and soft x-rays Suns, solar wind particles, cosmic dust, and larger bodies such as meteorites. The task is complicated by the fact that their impact, as a rule, is random, and its intensity and duration cannot be predicted, moreover, episodic phenomena are superimposed by cyclical processes associated with changes in the time of day, season, and the solar cycle. At present, at best, there is accumulated statistics of events on the dynamics of atmospheric parameters, but a theoretical description of the regularities has not yet been completed. A direct proportionality between the concentration of plasma particles in the ionosphere and solar activity has been definitely established. This is confirmed by the fact that a similar regularity was actually recorded according to the results of observations in 2007-2009 for the Earth's ionosphere, despite the fundamental difference in the magnetic field of these planets, which directly affects the ionosphere. And particle emissions solar corona, causing a change in the pressure of the solar wind, also entail a characteristic compression of the magnetosphere and ionosphere: the maximum plasma density drops to 90 km.

      Daily fluctuations

      Despite its rarefaction, the atmosphere nevertheless reacts to changes in the solar heat flux more slowly than the surface of the planet. So, in the morning period, the temperature varies greatly with height: a difference of 20 ° was recorded at a height of 25 cm to 1 m above the surface of the planet. With the rising of the Sun, cold air heats up from the surface and rises in the form of a characteristic swirl upwards, raising dust into the air - this is how dust devils are formed. In the near-surface layer (up to 500 m high) there is a temperature inversion. After the atmosphere has already warmed up by noon, this effect is no longer observed. The maximum is reached at about 2 o'clock in the afternoon. The surface then cools faster than the atmosphere and a reverse temperature gradient is observed. Before sunset, the temperature again decreases with height.

      The change of day and night also affects the upper atmosphere. First of all, ionization by solar radiation stops at night, however, the plasma continues to be replenished for the first time after sunset due to the flux from the day side, and then is formed due to impacts of electrons moving downward along the magnetic field lines (the so-called intrusion of electrons) - then the maximum observed at an altitude of 130-170 km. Therefore, the density of electrons and ions on the night side is much lower and is characterized by a complex profile, which also depends on the local magnetic field and varies in a non-trivial way, the regularity of which is not yet fully understood and described theoretically. During the day, the state of the ionosphere also changes depending on the zenith angle of the Sun.

      annual cycle

      Like on Earth, on Mars there is a change of seasons due to the inclination of the axis of rotation to the plane of the orbit, so in winter the polar cap grows in the northern hemisphere, and almost disappears in the southern, and after six months the hemispheres change places. At the same time, due to the rather large eccentricity of the planet's orbit at perihelion (winter solstice in the northern hemisphere), it receives up to 40% more solar radiation than in aphelion, and in the northern hemisphere, winter is short and relatively moderate, and summer is long, but cool, in in the south, on the contrary, summers are short and relatively warm, and winters are long and cold. In this regard, the southern cap in winter grows up to half the pole-equator distance, and the northern cap only up to a third. When summer comes at one of the poles, carbon dioxide from the corresponding polar cap evaporates and enters the atmosphere; the winds carry it to the opposite cap, where it freezes again. In this way, the carbon dioxide cycle occurs, which, along with the different sizes of the polar caps, causes a change in the pressure of the Martian atmosphere as it orbits the Sun. Due to the fact that in winter up to 20-30% of the entire atmosphere freezes in the polar cap, the pressure in the corresponding area drops accordingly.

      Seasonal variations (as well as daily ones) also undergo water vapor concentration - they are in the range of 1-100 microns. So, in winter the atmosphere is almost “dry”. Water vapor appears in it in the spring, and by mid-summer its amount reaches a maximum, following changes in surface temperature. During the summer-autumn period, water vapor is gradually redistributed, and its maximum content moves from the northern polar region to equatorial latitudes. At the same time, the total global vapor content in the atmosphere (according to Viking-1 data) remains approximately constant and is equivalent to 1.3 km 3 of ice. The maximum content of H 2 O (100 μm of precipitated water, equal to 0.2 vol%) was recorded in summer over the dark region surrounding the northern residual polar cap - at this time of the year the atmosphere above the ice of the polar cap is usually close to saturation.

      In the spring-summer period in the southern hemisphere, when dust storms are most actively formed, diurnal or semi-diurnal atmospheric tides are observed - an increase in pressure near the surface and thermal expansion of the atmosphere in response to its heating.

      The change of seasons also affects the upper atmosphere - both the neutral component (thermosphere) and the plasma (ionosphere), and this factor must be taken into account together with the solar cycle, and this complicates the task of describing the dynamics of the upper atmosphere.

      Long term change

      see also

      Notes

      1. Williams, David R. Mars Fact Sheet (indefinite) . National Space Science Data Center. NASA (September 1, 2004). Retrieved 28 September 2017.
      2. N. Mangold, D. Baratoux, O. Witasse, T. Encrenaz, C. Sotin. Mars: a small terrestrial planet : [English] ]// The Astronomy and Astrophysics Review. - 2016. - V. 24, No. 1 (December 16). - P. 15. - DOI: 10.1007/s00159-016-0099-5 .
      3. Atmosphere of Mars (indefinite) . UNIVERSE-PLANET // PORTAL TO ANOTHER DIMENSION
      4. Mars is a red star. Description of the area. Atmosphere and climate (indefinite) . galspace.ru - Solar System Exploration Project. Retrieved 29 September 2017.
      5. (English) Out of Thin Martian Air Astrobiology Magazine, Michael Schirber, 22 August 2011.
      6. Maxim Zabolotsky. General information about atmosphere Mars (indefinite) . spacegid.com(21.09.2013). Retrieved 20 October 2017.
      7. Mars Pathfinder - Science  Results - Atmospheric and Meteorological Properties (indefinite) . nasa.gov. Retrieved April 20, 2017.
      8. J. L. Fox, A. Dalgarno. Ionization, luminosity, and heating of the upper atmosphere of Mars: [English] ]// J Geophys Res. - 1979. - T. 84, issue. A12 (December 1). - S. 7315–7333. -

Today, not only science fiction writers in their stories talk about flights to Mars and its possible colonization, but also real scientists, businessmen, and politicians. Probes and rovers gave answers about the features of geology. However, for manned missions, one should find out whether Mars has an atmosphere and what its structure is.


General information

Mars has its own atmosphere, but it is only 1% of Earth's. Like Venus, it is predominantly carbon dioxide, but again, much thinner. The relatively dense layer is 100 km (for comparison, the Earth has 500-1000 km, according to various estimates). Because of this, there is no protection from solar radiation, and the temperature regime is practically not regulated. There is no air on Mars in the usual sense.

Scientists have established the exact composition:

  • Carbon dioxide - 96%.
  • Argon - 2.1%.
  • Nitrogen - 1.9%.

Methane was discovered in 2003. The discovery spurred interest in the Red Planet, with many countries launching exploration programs that led to talk of flight and colonization.

Due to the low density, the temperature regime is not regulated, therefore, the differences are on average 100 0 С. In the daytime, quite comfortable conditions of +30 0 С are established, and at night the surface temperature drops to -80 0 С. The pressure is 0.6 kPa (1 /110 from the earth indicator). On our planet, similar conditions are found at an altitude of 35 km. This is the main danger for a person without protection - he will not be killed by temperature or gases, but by pressure.

There is always dust on the surface. Due to the low gravity, the clouds rise up to 50 km. Strong temperature drops lead to the appearance of winds with gusts up to 100 m / s, so dust storms on Mars are common. They do not pose a serious threat due to the small concentration of particles in the air masses.

What are the layers of the atmosphere of Mars?

The force of gravity is less than Earth's, so the atmosphere of Mars is not so clearly divided into layers in terms of density and pressure. The homogeneous composition is preserved up to the mark of 11 km, then the atmosphere begins to separate into layers. Above 100 km, the density decreases to the minimum values.

  • Troposphere - up to 20 km.
  • Stratomesosphere - up to 100 km.
  • Thermosphere - up to 200 km.
  • Ionosphere - up to 500 km.

In the upper atmosphere there are light gases - hydrogen, carbon. Oxygen accumulates in these layers. Individual particles of atomic hydrogen propagate over a distance of up to 20,000 km, forming a hydrogen corona. There is no clear separation between the extreme regions and outer space.

upper atmosphere

At a mark of more than 20-30 km, the thermosphere is located - the upper regions. The composition remains stable up to an altitude of 200 km. Here there is high content atomic oxygen. The temperature is quite low - up to 200-300 K (from -70 to -200 0 C). Next comes the ionosphere, in which ions react with neutral elements.

lower atmosphere

Depending on the season, the boundary of this layer changes, and this zone is called the tropopause. Further on, the stratomesosphere extends, the average temperature of which is -133 0 C. On Earth, ozone is contained here, which protects against cosmic radiation. On Mars, it accumulates at an altitude of 50-60 km and then is practically absent.

Composition of the atmosphere

The earth's atmosphere consists of nitrogen (78%) and oxygen (20%), argon, carbon dioxide, methane, etc. are present in small quantities. Such conditions are considered optimal for the emergence of life. The composition of the air on Mars is very different. The main element of the Martian atmosphere is carbon dioxide - about 95%. Nitrogen accounts for 3%, and argon 1.6%. Total oxygen - no more than 0.14%.

This composition was formed due to the weak attraction of the Red Planet. The most stable was heavy carbon dioxide, which is constantly replenished as a result of volcanic activity. Light gases dissipate in space due to low gravity and the absence of a magnetic field. Nitrogen is held by gravity as a diatomic molecule, but splits under the influence of radiation, and in the form of single atoms flies into space.

The situation is similar with oxygen, but in the upper layers it reacts with carbon and hydrogen. However, scientists do not fully understand the features of the reactions. According to the calculations, the number carbon monoxide There should be more CO, but in the end it is oxidized to carbon dioxide CO2 and sinks to the surface. Separately, molecular oxygen O2 appears only after the chemical decomposition of carbon dioxide and water in the upper layers under the influence of photons. It refers to non-condensable substances on Mars.

Scientists believe that millions of years ago, the amount of oxygen was comparable to the earth's - 15-20%. It is not yet known exactly why conditions have changed. However, individual atoms do not volatilize as actively, and due to the greater weight, it even accumulates. To some extent, the reverse process is observed.

Other important elements:

  • Ozone is practically absent, there is one area of ​​accumulation 30-60 km from the surface.
  • Water content is 100-200 times less than in the driest region of the Earth.
  • Methane - emissions of an unknown nature are observed, and so far the most discussed substance for Mars.

Methane on Earth belongs to biogenic substances, therefore, it can potentially be associated with organic matter. The nature of the appearance and rapid destruction has not yet been explained, so scientists are looking for answers to these questions.

What happened to the atmosphere of Mars in the past?

Over the millions of years of the existence of the planet, the atmosphere changes in composition and structure. As a result of the research, evidence has emerged that liquid oceans existed on the surface in the past. However, now the water remains in small quantities in the form of steam or ice.

Reasons for the disappearance of fluid:

  • Low atmospheric pressure is not able to keep water in a liquid state for a long time, as it happens on Earth.
  • Gravity is not strong enough to hold vapor clouds.
  • Due to the absence of a magnetic field, matter is carried away by particles of the solar wind into space.
  • With significant temperature fluctuations, water can only be stored in a solid state.

In other words, the Martian atmosphere is not dense enough to hold water as a liquid, and the small force of gravity is not able to hold hydrogen and oxygen.
According to experts, favorable conditions for life on the Red Planet could have formed about 4 billion years ago. Perhaps there was life at that time.

The following causes of destruction are called:

  • Lack of protection from solar radiation and gradual depletion of the atmosphere over millions of years.
  • Impact with a meteorite or other space body that instantly destroyed the atmosphere.

The first reason is currently more likely, since no traces of a global catastrophe have yet been found. Similar conclusions were made thanks to the study of the autonomous station Curiosity. The rover has established the exact composition of the air.

The ancient atmosphere of Mars contained a lot of oxygen

Today, scientists have little doubt that there used to be water on the Red Planet. On numerous views of the outlines of the oceans. Visual observations are supported by specific studies. The rovers took soil samples in the valleys of the former seas and rivers, and the chemical composition confirmed the initial assumptions.

Under current conditions, any liquid water on the planet's surface will instantly evaporate because the pressure is too low. However, if in ancient times there were oceans and lakes, then the conditions were different. One of the assumptions is a different composition with an oxygen fraction of the order of 15-20%, as well as an increased proportion of nitrogen and argon. In this form, Mars becomes almost identical to our home planet - with liquid water, oxygen and nitrogen.

Other scientists suggest the existence of a full-fledged magnetic field that can protect against the solar wind. Its power is comparable to that of the earth, and this is another factor that speaks in favor of the presence of conditions for the origin and development of life.

Causes of Atmosphere Depletion

The peak of development falls on the Hesperian era (3.5-2.5 billion years ago). On the plain was a salty ocean comparable in size to the Arctic Ocean. The surface temperature reached 40-50 0 C, and the pressure was about 1 atm. There is a high probability of the existence of living organisms in that period. However, the period of "prosperity" was not long enough for a complex and even more intelligent life to arise.

One of the main reasons is the small size of the planet. Mars is smaller than Earth, so gravity and magnetic field are weaker. As a result, the solar wind actively knocked out the particles and literally cut off the shell layer by layer. The composition of the atmosphere began to change over 1 billion years, after which climate change became catastrophic. The decrease in pressure led to the evaporation of the liquid and temperature drops.

When we talk about climate change, we shake our heads sadly - oh, how much our planet has changed over the years. recent times how polluted its atmosphere is... However, if we want to see a true example of how fatal climate change can be, then we will have to look for it not on Earth, but beyond. Mars is very suitable for this role.

What was here millions of years ago cannot be compared with the picture of today. Today, Mars is a bitter cold on the surface, low pressure, a very thin and rarefied atmosphere. Before us lies only a pale shadow of the former world, the surface temperature of which was not much lower than the current temperature on earth, and full-flowing rivers rushed through the plains and gorges. Maybe there was even organic life here, who knows? All this is in the past.

What is the atmosphere of Mars made of?

Now it even rejects the possibility of living beings living here. Martian weather is shaped by many factors, including the cyclic growth and melting of ice caps, atmospheric water vapor, and seasonal dust storms. Sometimes, giant dust storms cover the entire planet at once and can last for months, turning the sky a deep red.

The atmosphere of Mars is about 100 times thinner than that of Earth, and 95 percent carbon dioxide. The exact composition of the Martian atmosphere is:

  • Carbon dioxide: 95.32%
  • Nitrogen: 2.7%
  • Argon: 1.6%
  • Oxygen: 0.13%
  • Carbon monoxide: 0.08%

In addition, in small quantities there are: water, nitrogen oxides, neon, heavy hydrogen, krypton and xenon.

How did the atmosphere of Mars come about? Just like on Earth - as a result of degassing - the release of gases from the bowels of the planet. However, the force of gravity on Mars is much less than on Earth, so most of the gases escape into the world space, and only a small part of them is able to stay around the planet.

What happened to the atmosphere of Mars in the past?

At the dawn of the existence of the solar system, that is, 4.5-3.5 billion years ago, Mars had a sufficiently dense atmosphere, due to which water could be in liquid form on its surface. Orbital photographs show the contours of vast river valleys, outlines ancient ocean on the surface of the red planet, and rovers have repeatedly found samples chemical compounds, which prove to us that the eyes do not lie - all these relief details familiar to the human eye on Mars were formed in the same conditions as on Earth.

There was no doubt that there was water on Mars, there are no questions here. The only question is, why did she end up disappearing?

The main theory in this regard looks something like this: once upon a time, Mars had, effectively reflecting solar radiation, however, over time, it began to weaken and about 3.5 billion years ago it practically disappeared (separate local centers of the magnetic field, and in terms of power quite comparable to the earth's, are on Mars even now). Since the size of Mars is almost half that of Earth, its gravity is much weaker than that of our planet. The combination of these two factors (the loss of the magnetic field and weak gravity) led to this. that the solar wind began to "knock out" light molecules from the atmosphere of the planet, gradually thinning it. So, in a matter of millions of years, Mars turned into the role of an apple, from which the skin was carefully cut with a knife.

The weakened magnetic field could no longer effectively "extinguish" cosmic radiation, and the sun turned from a source of life into a killer for Mars. And the thinned atmosphere could no longer retain heat, so the temperature on the planet's surface dropped to an average value of -60 degrees Celsius, only on a summer day at the equator, reaching +20 degrees.

Although the atmosphere of Mars is now about 100 times thinner than Earth's, it is still thick enough for the weather formation processes to actively occur on the red planet, precipitation fell, clouds and winds arose.

"Dust Devil" - a small tornado on the surface of Mars, photographed from the orbit of the planet

Radiation, dust storms and other features of Mars

Radiation near the surface of the planet is dangerous, however, according to NASA data obtained from the collection of analyzes by the Curiosity rover, it follows that even for a 500-day period of stay on Mars (+360 days on the way), astronauts (including protective equipment) would receive " dose" of radiation equal to 1 sievert (~100 roentgens). This dose is dangerous, but certainly will not kill an adult "on the spot." It is believed that 1 sievert of radiation received increases the astronaut's risk of developing cancer by 5%. According to scientists, for the sake of science, you can go to great hardships, especially the first step to Mars, even if it promises health problems in the future ... This is definitely a step into immortality!

On the surface of Mars, seasonally, hundreds of dust devils (tornadoes) rage, raising dust from iron oxides (rust, in a simple way) into the atmosphere, which abundantly covers the Martian wastelands. Martian dust is very fine, which, combined with low gravity, leads to the fact that a significant amount of it is always present in the atmosphere, reaching especially high concentrations in autumn and winter in the northern hemispheres, and in spring and summer in the southern hemispheres of the planet.

Dust storms on Mars- the largest in the solar system, capable of covering the entire surface of the planet and sometimes going for months. The main dust storm seasons on Mars are spring and summer.

The mechanism of such powerful weather phenomena is not fully understood, but with a high degree of probability is explained by the following theory: when big number dust particles rise into the atmosphere, which leads to its sharp heating to a great height. Warm masses of gases rush towards the cold regions of the planet, generating wind. Martian dust, as already noted, is very light, so a strong wind raises even more dust to the top, which in turn heats the atmosphere even more and generates even more strong winds, which in turn raise even more dust ... and so on!

There is no rain on Mars, and where can they come from in the cold at -60 degrees? But sometimes it snows. True, such snow consists not of water, but of carbon dioxide crystals, and its properties are more like fog than snow (the “snowflakes” are too small), but be sure that this is real snow! Just with local specifics.

In general, “snow” goes almost throughout the entire territory of Mars, and this process is cyclical - at night carbon dioxide freezes and turns into crystals, falling to the surface, and during the day it thaws and returns to the atmosphere again. However, in the northern south poles planets, in winter, frost reigns down to -125 degrees, therefore, having once fallen out in the form of crystals, the gas no longer evaporates, and lies in a layer until spring. Considering the size of the snow caps on Mars, is it necessary to say that in winter the concentration of carbon dioxide in the atmosphere drops by tens of percent? The atmosphere becomes even more rarefied, and as a result retains even less heat ... Mars is plunging into winter.

The main characteristics of Mars

© Vladimir Kalanov,
website"Knowledge is power".

Atmosphere of Mars

The composition and other parameters of the Martian atmosphere have been determined quite accurately by now. The atmosphere of Mars is composed of carbon dioxide (96%), nitrogen (2.7%) and argon (1.6%). Oxygen is present in negligible amounts (0.13%). Water vapor is presented as traces (0.03%). The pressure at the surface is only 0.006 (six thousandths) of the pressure at the Earth's surface. Martian clouds are made up of water vapor and carbon dioxide and look something like cirrus clouds above the Earth.

The color of the Martian sky is reddish due to the presence of dust in the air. Extremely rarefied air does not transfer heat well, so there is a large temperature difference in different parts of the planet.

Despite the rarefaction of the atmosphere, its lower layers represent a rather serious obstacle for spacecraft. So, the conical protective shells of the descent vehicles "Mariner-9"(1971) during the passage of the Martian atmosphere from its uppermost layers to a distance of 5 km from the surface of the planet, they were heated to a temperature of 1500 ° C. The Martian ionosphere extends from 110 to 130 km above the surface of the planet.

On the movement of Mars

Mars can be seen from Earth with the naked eye. Its apparent stellar magnitude reaches −2.9m (at its closest approach to the Earth), second only to Venus, the Moon and the Sun in brightness, but most of the time Jupiter is brighter than Mars for an earthly observer. Mars moves around the Sun in an elliptical orbit, then moving away from the star at 249.1 million km, then approaching it up to a distance of 206.7 million km.

If you carefully observe the movement of Mars, you can see that during the year the direction of its movement across the sky changes. By the way, ancient observers noticed this. At a certain point, it seems that Mars is moving in the opposite direction. But this movement is only apparent from the Earth. Mars, of course, cannot perform any reverse movement in its orbit. And the appearance of a reverse movement is created because the orbit of Mars in relation to the orbit of the Earth is external, and average speed orbit around the Sun is higher for the Earth (29.79 km/s) than for Mars (24.1 km/s). At the moment when the Earth begins to overtake Mars in its movement around the Sun, and it seems that Mars began the reverse or, as astronomers call it, retrograde motion. The diagram of the reverse (retrograde) movement illustrates this phenomenon well.

The main characteristics of Mars

Name of parameters Quantitative indicators
Average distance to the Sun 227.9 million km
Minimum distance to the Sun 206.7 million km
Maximum distance to the Sun 249.1 million km
Equator diameter 6786 km (Mars is almost half the size of the Earth in size - its equatorial diameter is ~ 53% of the Earth's)
Average orbital speed around the Sun 24.1 km/s
Period of rotation around its own axis (Sidereal equatorial period of rotation) 24h 37 min 22.6 s
Period of revolution around the sun 687 days
Known natural satellites 2
Mass (Earth = 1) 0.108 (6.418 × 10 23 kg)
Volume (Earth = 1) 0,15
Average density 3.9 g/cm³
Average surface temperature minus 50°C (temperature difference is from -153°C at the pole in winter and up to +20°C at the equator at noon)
Axis Tilt 25°11"
Orbital inclination with respect to the ecliptic 1°9"
Surface pressure (Earth = 1) 0,006
Composition of the atmosphere CO 2 - 96%, N - 2.7%, Ar - 1.6%, O 2 - 0.13%, H 2 O (vapors) - 0.03%
Acceleration of free fall at the equator 3.711 m/s² (0.378 Earth)
parabolic speed 5.0 km/s (for Earth 11.2 km/s)

The table shows with what high accuracy the main parameters of the planet Mars are determined. This is not surprising, given that astronomical observations and research are now using the most modern scientific methods and high precision equipment. But with a completely different feeling, we treat such facts from the history of science, when scientists of past centuries, who often did not have any astronomical instruments at their disposal, except for the simplest telescopes with a small increase (maximum 15-20 times), made accurate astronomical calculations and even discovered the laws of motion of celestial bodies.

For example, let's recall that the Italian astronomer Giandomenico Cassini already in 1666 (!) determined the time of rotation of the planet Mars around its axis. His calculations gave a result of 24 hours and 40 minutes. Compare this result with the period of rotation of Mars around its axis, determined with the help of modern technical means (24 hours 37 minutes 23 seconds). Are our comments needed here?

Or such an example. in the very early XVII century, he discovered the laws of planetary motion, having neither precise astronomical instruments nor a mathematical apparatus for calculating the areas of such geometric shapes like an ellipse and an oval. Suffering from a visual defect, he made the most accurate astronomical measurements.

Similar examples show great importance activity and enthusiasm in science, as well as devotion to the cause that a person serves.

© Vladimir Kalanov,
"Knowledge is power"

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Mars is the fourth planet from the Sun and the last of the planets terrestrial group. Like the rest of the planets solar system(not counting the Earth) is named after the mythological figure - the Roman god of war. In addition to its official name, Mars is sometimes referred to as the Red Planet, referring to the brown-red color of its surface. With all this, Mars is the second smallest planet in the solar system after.

For most of the nineteenth century, life was thought to exist on Mars. The reason for this belief lies partly in error and partly in human imagination. In 1877, astronomer Giovanni Schiaparelli was able to observe what he thought were straight lines on the surface of Mars. Like other astronomers, when he noticed these stripes, he suggested that such directness is associated with the existence on the planet intelligent life. The version popular at that time about the nature of these lines was the assumption that they were irrigation canals. However, with the development of more powerful telescopes in the early twentieth century, astronomers were able to see the Martian surface more clearly and determine that these straight lines were just an optical illusion. As a result, all earlier assumptions about life on Mars were left without evidence.

Much of the science fiction written during the twentieth century was a direct consequence of the belief that life existed on Mars. From little green men to tall, laser-wielding invaders, Martians have been the focus of many television and radio programs, comics, films, and novels.

Despite the fact that the discovery of Martian life in the eighteenth century turned out to be false as a result, Mars remained for the scientific community the most life-friendly (other than Earth) planet in the solar system. Subsequent planetary missions were no doubt dedicated to the search for any form of life on Mars. So a mission called Viking, carried out in the 1970s, conducted experiments on Martian soil in the hope of finding microorganisms in it. At the time, it was believed that the formation of compounds during experiments could be the result of biological agents, but later it was found that the compounds chemical elements can be created without biological processes.

However, even these data did not deprive scientists of hope. Finding no signs of life on the surface of Mars, they suggested that all the necessary conditions could exist below the surface of the planet. This version is still relevant today. At the very least, such planetary missions of the present as ExoMars and Mars Science involve checking all options the existence of life on Mars in the past or present, on the surface and below it.

Atmosphere of Mars

The composition of the atmosphere of Mars is very similar to the atmosphere, one of the least hospitable atmospheres in the entire solar system. The main component in both environments is carbon dioxide (95% for Mars, 97% for Venus), but there is a big difference - there is no greenhouse effect on Mars, so the temperature on the planet does not exceed 20 ° C, in contrast to 480 ° C on the surface of Venus . Such a huge difference is due to the different density of the atmospheres of these planets. At a comparable density, the atmosphere of Venus is extremely thick, while Mars has a rather thin atmospheric layer. Simply put, if the thickness of the atmosphere of Mars were more significant, then it would resemble Venus.

In addition, Mars has a very rarefied atmosphere - atmospheric pressure is only about 1% of the pressure on. This is equivalent to a pressure of 35 kilometers above the Earth's surface.

One of the earliest directions in the study of the Martian atmosphere is its influence on the presence of water on the surface. Despite the fact that the polar caps contain water in a solid state, and the air contains water vapor formed as a result of frost and low pressure, today all studies indicate that the "weak" atmosphere of Mars does not favor the existence of water in a liquid state on the surface. planets.

However, relying on the latest data from Martian missions, scientists are confident that liquid water exists on Mars and is one meter below the surface of the planet.

Water on Mars: speculation / wikipedia.org

However, despite the thin atmospheric layer, Mars has quite acceptable weather conditions by earthly standards. Most extreme forms this weather are winds, dust storms, frosts and fogs. As a result of such weather activity, significant traces of erosion have been observed in some areas of the Red Planet.

Another interesting point about the Martian atmosphere is that, according to several modern scientific research, in the distant past, it was dense enough for the existence of oceans on the surface of the planet from water in a liquid state. However, according to the same studies, the atmosphere of Mars has been dramatically changed. The leading version of such a change at the moment is the hypothesis of a collision of the planet with another sufficiently voluminous cosmic body, which led to the loss of most of Mars's atmosphere.

The surface of Mars has two significant features, which, by an interesting coincidence, are associated with differences in the hemispheres of the planet. The fact is that the northern hemisphere has a fairly smooth relief and only a few craters, while the southern hemisphere is literally dotted with hills and craters of various sizes. In addition to the topographical differences that indicate the difference in the relief of the hemispheres, there are also geological ones - studies indicate that areas in the northern hemisphere are much more active than in the southern.

On the surface of Mars is the largest volcano known to date - Olympus Mons (Mount Olympus) and the largest known canyon - Mariner (Mariner Valley). Nothing more grandiose has yet been found in the solar system. The height of Mount Olympus is 25 kilometers (this is three times higher than Everest, the most high mountain on Earth), and the diameter of the base is 600 kilometers. The Mariner Valley is 4,000 kilometers long, 200 kilometers wide and almost 7 kilometers deep.

To date, the most significant discovery regarding the Martian surface has been the discovery of channels. A feature of these channels is that they, according to NASA experts, were created by running water, and thus are the most reliable evidence for the theory that in the distant past, the surface of Mars greatly resembled the earth's.

The most famous peridolia associated with the surface of the Red Planet is the so-called "Face on Mars". The relief really looked very much like a human face when the first image of a certain area was taken by the Viking I spacecraft in 1976. Many people at the time considered this image to be real proof that intelligent life existed on Mars. Subsequent shots showed that this is just a game of lighting and human fantasy.

Like other terrestrial planets, three layers are distinguished in the interior of Mars: the crust, mantle, and core.
Although exact measurements have not yet been made, scientists have made certain predictions about the thickness of the Martian crust based on data on the depth of the Mariner Valley. The deep, vast system of the valley, located in the southern hemisphere, could not exist if the crust of Mars was not much thicker than the earth. Preliminary estimates indicate that the thickness of the Martian crust in the northern hemisphere is about 35 kilometers and about 80 kilometers in the southern.

Quite a lot of research has been devoted to the core of Mars, in particular, to find out whether it is solid or liquid. Some theories have pointed to the absence of a strong enough magnetic field as a sign of a solid core. However, in the last decade, the hypothesis that the core of Mars is liquid, at least in part, is gaining more and more popularity. This was indicated by the discovery of magnetized rocks on the planet's surface, which may be a sign that Mars has or had a liquid core.

Orbit and rotation

Mars' orbit is notable for three reasons. First, its eccentricity is the second largest of all the planets, only Mercury is smaller. In this elliptical orbit, Mars' perihelion is 2.07 x 108 kilometers, much further than its aphelion, 2.49 x 108 kilometers.

Secondly, scientific evidence suggests that such high degree eccentricity was far from always present, and, perhaps, was less than the Earth's at some point in the history of the existence of Mars. The reason for this change, scientists call the gravitational forces of neighboring planets that affect Mars.

Thirdly, of all the terrestrial planets, Mars is the only one on which the year lasts longer than on Earth. Naturally, this is related to its orbital distance from the Sun. One Martian year is equal to almost 686 Earth days. A Martian day lasts approximately 24 hours and 40 minutes, which is the time it takes for the planet to complete one complete revolution on its axis.

Another notable similarity between the planet and Earth is its axial tilt, which is approximately 25°. This feature indicates that the seasons on the Red Planet follow each other in exactly the same way as on Earth. However, the hemispheres of Mars experience completely different temperature regimes for each season, different from those on Earth. This is again due to the much greater eccentricity of the planet's orbit.

SpaceX And ​​plans to colonize Mars

So we know that SpaceX wants to send humans to Mars in 2024, but their first Martian mission will be the launch of the Red Dragon capsule in 2018. What steps is the company going to take to achieve this goal?

  • 2018 year. Launch of the Red Dragon space probe to demonstrate technology. The goal of the mission is to reach Mars and do some surveys on the landing site on a small scale. Possibly a supply additional information for NASA or space agencies of other states.
  • 2020 launch spaceship Mars Colonial Transporter MCT1 (unmanned). The purpose of the mission is to send cargo and return samples. Large-scale demonstrations of technology for habitation, life support, energy.
  • 2022 Launch of the Mars Colonial Transporter MCT2 spacecraft (unmanned). Second iteration of MCT. At this time, MCT1 will be on its way back to Earth, carrying Martian samples. MCT2 is supplying equipment for the first manned flight. The MCT2 ship will be ready for launch as soon as the crew arrives on the Red Planet in 2 years. In the event of trouble (as in the movie "The Martian"), the team will be able to use it to leave the planet.
  • 2024 Third iteration of the Mars Colonial Transporter MCT3 and first manned flight. At that time, all technologies will prove their performance, MCT1 will make a trip to Mars and back, and MCT2 is ready and tested on Mars.

Mars is the fourth planet from the Sun and the last of the terrestrial planets. The distance from the Sun is about 227,940,000 kilometers.

The planet is named after Mars, the Roman god of war. He was known to the ancient Greeks as Ares. It is believed that Mars received such an association because of the blood-red color of the planet. Due to its color, the planet was also known to other ancient cultures. The first Chinese astronomers called Mars the "Star of Fire", and the ancient Egyptian priests designated it as "Her Desher", which means "red".

The landmass on Mars is very similar to that on Earth. Despite the fact that Mars occupies only 15% of the volume and 10% of the mass of the Earth, it has a land mass comparable to our planet as a result of the fact that water covers about 70% of the Earth's surface. At the same time, the surface gravity of Mars is about 37% of the gravity on Earth. This means that you can theoretically jump three times higher on Mars than on Earth.

Only 16 out of 39 missions to Mars were successful. Since the Mars 1960A mission launched in the USSR in 1960, a total of 39 descent orbiters and rovers have been sent to Mars, but only 16 of these missions have been successful. In 2016, a probe was launched as part of the Russian-European ExoMars mission, the main objectives of which will be to search for signs of life on Mars, study the surface and topography of the planet, and map potential hazards from environment for future manned missions to Mars.

Debris from Mars has been found on Earth. It is believed that traces of some of the Martian atmosphere have been found in meteorites that have bounced off the planet. After they left Mars, these meteorites for a long time, for millions of years, flew around the solar system among other objects and space debris, but were captured by the gravity of our planet, fell into its atmosphere and collapsed to the surface. The study of these materials allowed scientists to learn a lot about Mars even before the start of space flights.

In the recent past, people were convinced that Mars was home to intelligent life. This was largely influenced by the discovery of straight lines and ditches on the surface of the Red Planet by the Italian astronomer Giovanni Schiaparelli. He believed that such straight lines cannot be created by nature and are the result of intelligent activity. However, it was later proven that this was nothing more than an optical illusion.

The highest planetary mountain known in the solar system is on Mars. It is called Olympus Mons (Mount Olympus) and rises 21 kilometers in height. It is believed that this is a volcano that was formed billions of years ago. Scientists have found enough evidence that the age of the volcanic lava of the object is quite small, which may be evidence that Mount Olympus may still be active. However, there is a mountain in the solar system that Olympus is inferior in height to - this is the central peak of Reyasilvia, located on the asteroid Vesta, whose height is 22 kilometers.

Dust storms occur on Mars - the most extensive in the solar system. This is due to the elliptical shape of the trajectory of the planet's orbit around the Sun. The path of the orbit is more elongated than that of many other planets, and this oval shape of the orbit results in ferocious dust storms that engulf the entire planet and can last for many months.

The Sun appears to be about half its visual Earth size when viewed from Mars. When Mars is closest to the Sun in its orbit, and its southern hemisphere is facing the Sun, the planet experiences a very short but incredibly hot summer. At the same time, a short but cold winter sets in in the northern hemisphere. When the planet is further from the Sun, and pointed towards it by the northern hemisphere, Mars experiences a long and mild summer. At the same time, a long winter sets in in the southern hemisphere.

With the exception of the Earth, scientists consider Mars the most suitable planet for life. Leading space agencies are planning a series of spaceflights over the next decade to find out if Mars has the potential for life to exist and whether it is possible to build a colony on it.

Martians and aliens from Mars have long been the main candidates for the role of extraterrestrial aliens, which has made Mars one of the most popular planets in the solar system.

Mars is the only planet in the system other than Earth that has polar ice. Solid water has been discovered under the polar caps of Mars.

Just like on Earth, Mars has seasons, but they last twice as long. This is because Mars is tilted on its axis by about 25.19 degrees, which is close to Earth's axial tilt (22.5 degrees).

Mars has no magnetic field. Some scientists believe that it existed on the planet about 4 billion years ago.

The two moons of Mars, Phobos and Deimos, were described in Gulliver's Travels by author Jonathan Swift. This was 151 years before they were discovered.

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