The composition of the atmosphere of Mars and the Earth. The atmosphere of Mars is the chemical composition, weather conditions and climate in the past
The atmosphere of Mars is less than 1% of the earth, so it does not protect the planet from the radiation of the Sun and does not preserve heat on the surface. So briefly you can describe it, but let's consider it in more detail.
Mars's atmosphere was open before the flight of automatic interplanetary stations to the planet. Thanks to the confrontations of the planet, which happen every three years and spectral analysis, the astronomers already knew that it had a very homogeneous composition, more than 95% of which is CO2.
The color of the Martian sky from the Viking Lander landing module 1. At 1742 Sol (Martian day) is visible to dust storm.
In the 20th century, thanks to the interplanetary probes, we learned that the atmosphere of Mars and its temperature are very interrelated, because thanks to the transfer of the smallest particles of iron oxide, huge dust storms arise, which can cover half of the planet, simultaneously raising its temperature.
Approximate composition
The gas shell of the planet consists of consisting of 95% carbon dioxide, 3% nitrogen, 1.6% of argon, and trace amounts of oxygen, water vapor and other gases. In addition, it is very much filled with small dust particles (mainly of iron oxide), which give her a reddish tint. Thanks to the information about the particles of iron oxide, answer the question of what color atmosphere is not difficult.
Carbon dioxide
Dark dunes - the result of the sublimation of frozen carbon dioxide, which melted in the spring and escaped into the discharged atmosphere, leaving behind such traces.
Why is the atmosphere of the Red Planet consists of carbon dioxide? There are no tactics on the planet for billions of years. The lack of movement of the plates allowed volcanic points to spew magma on the surface of millions of years in a row. Carbon dioxide is also an eruption product and this is the only gas that is constantly updated by the atmosphere, actually this is actually the only reason why it exists. In addition, the planet lost his magnetic fieldThat contributed to the fact that lighter gases were carried out by the sunshine. Due to continuous eruptions, many large volcanic mountains appeared. Mount Olympus, is the largest mountain in the solar system.
Scientists believe that Mars lost his entire atmosphere, due to the fact that he lost its magnetosphere about 4 billion years ago. Once the gas shell of the planet was tight and the magnetosphere protected from the solar wind to the planet. Sunny wind, the atmosphere and the magnetosphere are strongly interrelated. Solar particles interacts with the ionosphere and takes the molecule from it, reducing the density. This is a randering to the question where the atmosphere is done. These ionized particles were found by spacecraft, in the space behind Mars. This leads to the fact that on the surface pressure on average 600 Pa, compared with average pressure on Earth 101300 Pa.
Methane
The relatively large amount of methane was discovered relatively recently. This unexpected find showed that the atmosphere contains methane in the proportion of 30 parts per billion. This gas appears from different regions of the planet. The data suggests that there are two main methane sources.
Sunset of the Sun, Blue Sky Color is due, partly, the presence of methane
It is believed that Mars produces about 270 tons of methane per year. In accordance with the conditions on the planet, methane collapses quickly, about 6 months. In order for methane to exist in the quantities detected, there must be active sources below the surface. Volcanic activity and serpentine are the most likely causes of methane formation.
By the way, Methane is one of the reasons why the atmosphere of the planet is blue at sunset. Methane scatters blue, rather than other colors.
Methane is a by-product of life, as well as the result of vulcanism, geothermal processes, and hydrothermal activity. Methane is an unstable gas, so the planet should have a source that constantly replenishes it. It should be very active, because studies have shown that methane is destroyed in less than a year.
Quantitative composition
The chemical composition of the atmosphere: It consists of more than 95% carbon dioxide, 95.32%, if you are accurate. Gas are distributed as follows:
Carbon dioxide 95.32%
Nitrogen 2.7%
Argon 1.6%
Oxygen 0.13%
Carbon Oxide 0.07%
Water vapor 0.03%
Nitrogen oxide 0.0013%
Structure
The atmosphere is divided into four main layers: lower, medium, upper and ecosphere. Bottom layers are a warm area (about 210 K). It is heated from dust in the air (dust 1.5 μm in the diameter) and thermal radiation from the surface.
It should be noted that, despite the very large rareness, the concentration of carbon dioxide, in the gas shell of the planet, is approximately 23 times more than in our. Therefore, not such a friendly atmosphere of Mars, it is impossible to breathe in it not only to people, but also to other earthly organisms.
The average is similar to earthly. The upper layers of the atmosphere heats up from the solar wind and there the temperature is much higher than on the surface. It warmly causes the gas to leave the gas shell. The ecosphere begins approximately 200 km from the surface and does not have a clear boundary. As you can see, the temperature distribution in height is quite predictable for the planet of the earth group.
Weather on Mars
The forecast for Mars is usually very bad. See Mars weather forecast for Mars. The weather is changing every day and sometimes even every hour. It seems unusual for the planet, which has an atmosphere of a component of only 1% of the earth. Despite this, the climate of Mars and total temperature The planets also strongly affect each other as on earth.
Temperature
In summer, daytime temperatures in the equator can reach up to 20 ° C. At night, the temperature can be lowered to -90 p. 110 degrees of difference in one day, can create dust tornads and dust storms that cover the whole planet for several weeks. Winter temperatures are extremely low -140 C. Carbon dioxide freezes and turns into dry ice. The Martian North Pole has a meter layer of dry ice in winter, while the South Pole is constantly covered with eight meters of dry ice.
Clouds
Since the radiation of the sun and the solar wind is constantly bombarding the planet, liquid water can not exist, so there is no rain on Mars. Sometimes, however, clouds appear and snow starts to fall. Clouds on Mars are very small and thin.
Scientists believe that some of them consist of small particles of water. The atmosphere contains water vapor in minor quantities. At first glance, it may seem that the clouds cannot exist on the planet.
And yet on Mars, there are conditions for the formation of clouds. On the planet it is so cold that the water in these clouds never falls in the form of rain, but it goes in the form of snow in the upper layers of the atmosphere. Scientists observed it several times, and there is no evidence that the snow does not reach the surface.
Dust
As the atmosphere affects the temperature mode to see quite easily. The most significant event is dust storms that locally heat the planet. They occur due to the temperature difference on the planet, and the surface is covered with light dust, which even such a weak wind raises.
These storms are dug solar panels, which makes it impossible to long-term research on the planet. Fortunately, the storms alternate with the wind, which blows up the accumulated dust from the panels. But the atmosphere of Curiositi should be prevented in a position, the advanced American rover is equipped with a nuclear thermogenerator and to him, interruptions with sunlight Not terrible, unlike the other Opportunity Marshode, working on solar panels.
Such a mercier is not afraid no dust storms
Carbon dioxide
As already mentioned, the Gas Sheath of the Red Planet at 95 consists of carbon dioxide. It can freeze and fall on the surface. Approximately 25% of atmospheric carbon dioxide condenses in the polar hats in the form of solid ice (dry ice). This is due to the fact that the Martian poles are not exposed to sunlight during the winter period.
When sunlight falls on the pole, the ice goes into a gaseous form and evaporates back. Thus, there is a significant change in pressure per year.
Dust Solochi
Dusty tornhead with a height of 12 kilometers and 200 meters in diameter
If you have ever been in a desert terrain, then saw tiny dust sludge, which, as if arising from nowhere. Dust sludge on Mars are a bit more sinners than on Earth. In comparison with ours, the atmosphere of Krasnoyo Planet has a density of 100 times smaller. Therefore, tornadoes are more like a tornado rising a few kilometers in the air and having hundreds of meters in diameter. This partly explains that in comparison with our planet, the atmosphere is red - dust storms and fine dust from iron oxide. Also, the color of the planet's gas shell can change both at sunset when the sun sits down, methane dispels the blue part of the world is stronger than the rest, so the sunset on the planet is blue.
Mars - the fourth for the distance from the Sun and the seventh (penultimate) in the size of the planet of the solar system; The mass of the planet is 10.7% of the mass of the earth. Named in honor of Mars - the Ancient Roman God of war, corresponding to the ancient Greek arrest. Sometimes Mars is called the "red planet" due to a reddish shade of the surface attached to it iron oxide.
Mars - Planet of the earth's group with a rarefied atmosphere (the pressure of the surface is 160 times less than the earth). The peculiarities of the surface relief of Mars can be considered shock craters like lunar, as well as volcanoes, valleys, deserts and polar glacial caps like terrestrial.
Mars has two natural satellites - Phobos and Dimimos (translated from the ancient Greek - "fear" and "horror" - the names of two sons of Ares, accompanying him in battle), which are relatively small (Phobos - 26x21 km, Dimimos - 13 km in diameter ) And have an incorrect form.
Great confrontations of Mars, 1830-2035.
| Year | date | Distance, a. e. |
|---|---|---|
| 1830 | September 19. | 0,388 |
| 1845 | August 18 | 0,373 |
| 1860 | July 17th | 0,393 |
| 1877 | September 5 | 0,377 |
| 1892 | August 4 | 0,378 |
| 1909 | September 24 | 0,392 |
| 1924 | August 23 | 0,373 |
| 1939 | July 23 | 0,390 |
| 1956 | 10 September | 0,379 |
| 1971 | August 10 | 0,378 |
| 1988 | September 22nd | 0,394 |
| 2003 | August 28 | 0,373 |
| 2018 | July 27. | 0,386 |
| 2035 | September 15th | 0,382 |
Mars - the fourth for the distance from the Sun (after Mercury, Venus and Earth) and the seventh size (exceeding the mass and diameter of only Mercury) of the planet of the solar system. The mass of Mars is 10.7% of the mass of the Earth (6,423 · 1023 kg against 5,9736 · 1024 kg for the Earth), the volume is 0.15 of the volume of the Earth, and the average linear diameter is 0.53 of the diameter of the Earth (6800 km).
Mars relief has many unique features. Martian extinct volcano Mount Olympus is the highest mountain in the solar system, and Mariner Valley is the largest canyon. In addition, in June 2008, three articles published in the journal "Nature" presented evidence of existence in the northern hemisphere of Mars of the largest known shock crater in the solar system. Its length is 10,600 km, and the width is 8500 km, which is about four times more than the largest shock crater, and also discovered on Mars near his southern pole.
In addition to the similarity of the surface relief, Mars has a period of rotation and a change in the seasons of the year similar to the earth, but its climate is much colder and land of terrestrial.
Up to the first span of Mars spacecraft In 1965, Mariner-4 in 1965 believed that there were water in liquid state on its surface. This opinion was based on observations of periodic changes in bright and dark areas, especially in polar latitudes, which were similar to the continents and the sea. Dark grooves on the surface of Mars were interpreted by some observers as irrigation canals for liquid water. Later it was proved that these furrows were optical illusion.
Due to low pressure, water cannot exist in a liquid state on the surface of Mars, but it is likely that in the past the conditions were different, and therefore the presence of primitive life on the planet cannot be excluded. On July 31, 2008, water in the state of ice was discovered on Mars the NASA spacecraft "Phoenix" (English "Phoenix).
In February 2009, the orbital research group in the orbit of Mars has numbered three functioning spacecraft: Mars Odyssey, Mars-Express and Martian intelligence satellite, this is more than about any other planet, in addition to the Earth.
The surface of Mars was currently investigated by two Marshodes: "Spirit" and "Opportunities". On the surface of Mars there are also several inactive landing modules and rinsing, completed studies.
The geological data collected by them suggest that most of the surface of Mars had previously covered the water. Observations over the past decade have made it possible to detect weak geyser activity in some places on the surface of Mars. According to observations from the Space Agency "Mars Global Serversior", some of the southern polar cap of Mars are gradually retreating.
Mars can be seen from the ground with a naked eye. Its visible star magnitude reaches 2.91m (with maximum convergence from the earth), yielding only Jupiter in brightness (and then not always during the great confrontation) and Venus (but only in the morning or in the evening). As a rule, during the Great confrontation, Orange Mars is the brightest object of the earthly night sky, but this happens only once every 15-17 years for one to two weeks.
Orbital characteristics
The minimum distance from Mars to the Earth is 55.76 million km (when the land is accurate between the Sun and Mars), the maximum is about 401 million km (when the sun is exactly between Earth and Mars).
The average distance from Mars to the Sun is 228 million km (1.52 a. E.), The treatment period around the Sun is 687 Earth days. The orbit of Mars has a rather noticeable eccentricity (0.0934), so the distance to the Sun varies from 206.6 to 249.2 million km. The inclination of the orbit of Mars is 1.85 °.
Mars is closest to the ground during the confrontation when the planet is in the direction opposite to the sun. The confrontation is repeated every 26 months at different points of the orbits of Mars and Earth. But once every 15-17 years of confrontation occurs at the time when Mars is close to his perigelium; In these so-called great confrontations (the latter in August 2003), the distance to the planet is minimal, and Mars reaches the greatest angular size of 25.1 "and brightness of 2.88m.
Comparison of land size (average radius 6371 km) and Mars (average radius 3386.2 km)
According to the linear size of Mars almost twice the ground - its equatorial radius is 3396.9 km (53.2% of the earth). The surface area of \u200b\u200bMars is approximately equal to the Sushi Square on Earth.
The polar radius of Mars is about 20 km less than equatorial, although the period of rotation at the planet is greater than that of the Earth, which gives reason to assume the change in the speed of rotation of Mars with time.
The mass of the planet is 6.418 · 1023 kg (11% of the mass of the Earth). Acceleration free fall at the equator is 3.711 m / s (0.378 Earth); The first cosmic velocity is 3.6 km / s and the second - 5,027 km / s.
The period of rotation of the planet is 24 hours 37 minutes 22.7 seconds. Thus, the Martian year consists of 668.6 Martian sunny days (called Sola).
Mars rotates around his axis, inclined to perpendicular orbit plane at an angle of 24 ° 56?. The inclination of the axis of rotation of Mars provides a change in the time of the year. At the same time, the elongation of the orbit leads to a large difference in their duration - so, the northern spring and summer, together taken, last 371 Salts, that is, more than half of the Martian year. At the same time, they fall on the site of the orbit of Mars, remote from the sun. Therefore, on Mars, the north summer is long and cool, and the southern is short and roast.
Atmosphere and climate
The atmosphere of Mars, the photo of the orbiter "Viking", 1976. Left is visible "Crater-Smiley" Galle
The temperature on the planet ranges from -153 on the pole in winter and to more than +20 ° C at the equator at noon. The average temperature is -50 ° C.
The atmosphere of Mars, consisting mainly of carbon dioxide, is very solved. The pressure at the surface of Mars is 160 times smaller than the earth - 6.1 mbar on average surface level. Because of the large height difference on Mars, the surface pressure changes greatly. Approximate atmosphere thickness - 110 km.
According to NASA (2004), the atmosphere of Mars consists of 95.32% of carbon dioxide; It also contains 2.7% nitrogen, 1.6% argon, 0.13% oxygen, 210 ppm water vapor, 0.08% carbon monoxide, nitrogen oxide (NO) - 100 PPM, neon (NE) - 2, 5 ppm, Halfwater water hydrogen-deuterium oxygen (HDO) 0.85 PPM, Crypton (Kr) 0.3 ppm, xenon (XE) - 0.08 ppm.
According to the released apparatus of AMS "Viking" (1976), about 1-2% of argon were determined in the Martian atmosphere, 2-3% of nitrogen, and 95% - carbon dioxide. According to AMC "Mars-2" and "Mars-3", the lower boundary of the ionosphere is located at an altitude of 80 km, the maximum electron concentration of 1.7 · 105 electron / cm3 is located at an altitude of 138 km, the other two maxima are at altitudes 85 and 107 km.
The radio station of the atmosphere on radio waves 8 and 32 cm AMC "MARS-4" February 10, 1974 showed the presence of a night ionosphere of Mars with the main maximum ionization at an altitude of 110 km and the electron concentration of 4.6 · 103 electron / cm3, as well as secondary maxima at height 65 and 185 km.
Atmosphere pressure
According to NASA for 2004, the atmosphere pressure on average radius is 6.36 MB. The density of the surface is ~ 0.020 kg / m3, the total weight of the atmosphere ~ 2.5 · 1016 kg.
Changing the atmospheric pressure on Mars, depending on the time of day, recorded by the Mars Pathfinder landing module in 1997.
Unlike the Earth, the mass of the Martian atmosphere varies greatly during the year due to the melting and the intention of polar hats containing carbon dioxide. During the winter, 20-30 percent of the entire atmosphere is fried on the polar hat consisting of carbon dioxide. Seasonal pressure drops, by different sources, make up the following values:
According to NASA (2004): from 4.0 to 8.7 mbar on average radius;
According to Encarta (2000): from 6 to 10 mbar;
According to Zubrin and Wagner (1996): from 7 to 10 mbar;
According to the Viking-1 landing apparatus: from 6.9 to 9 mbar;
According to the landing apparatus Mars Pathfinder: from 6.7 mbar.
Hellas Impact Basin (Hellas Impact Basin) - the deepest place where you can detect the highest atmospheric pressure on Mars
At the landing site of the AMS Mars-6 probe in the Eritrea Sea area, the pressure was recorded at 6.1mm, which was considered an average pressure on the planet at that time, and the height and depths on Mars were considered. According to this apparatus obtained during the descent, the tropopause is located at an altitude of about 30 km, where the pressure is 5 · 10-7 g / cm3 (as on Earth at an altitude of 57 km).
The region of Ellade (Mars) is so deep that the atmospheric pressure reaches about 12.4 millibers, which is above the triple water point (~ 6.1 MB) and below the boiling point. At a sufficiently high temperature, water could exist there in a liquid state; At such a pressure, however, water boils and turns into steam already at +10 ° C.
At the top of the highest 27-kilometer volcano Olympus, the pressure may be from 0.5 to 1 mbar (ZURK 1992).
Before landing on the surface of the Mars of landing modules, the pressure was measured due to the weakening of radio signals with AMS Mariner-4, Mariner-6 and Marinener-7 when they were found for the Martian disk - 6.5 ± 2.0 MB at the middle surface level, which in 160 times less earthly; The same result was shown by spectral observations of AMC MARS-3. At the same time, in the mid-level areas (for example, in Martian Amazonia), the pressure, according to these measurements, reaches 12 MB.
Starting from the 1930s. Soviet astronomers tried to determine the pressure of the atmosphere by photographic photometry using the brightness distribution along the disk diameter in different ranges of light waves. French scientists B.LO and O.Dolfyus produced for this purpose to observe the polarization of the diffused atmosphere of Mars of Light. A summary of optical observations has been published by American astronomer J.-de Vobuler in 1951, and there was a pressure of 85 MB, highly over-15 times due to noise from the side of atmospheric dust.
Climate
Microscopic photo of gematite concrete size 1.3 cm, shot by the rational "Opponuniti" on March 2, 2004, shows the presence in the past of liquid water
The climate, like on earth, is seasonal. In the cold season, even outside the polar caps on the surface can be formed by light frost. The "Phoenix" apparatus recorded the snowfall, but the snowflakes evaporated without reaching the surface.
According to NASA (2004), the average temperature is ~ 210 k (-63 ° C). According to the planting devices, Viking, the daily temperature range is from 184 k to 242 k (from -89 to -31 ° C) (Viking-1), and wind speed: 2-7 m / s (summer), 5-10 m / C (autumn), 17-30 m / s (dust storm).
According to the Mars-6 planting probe, the average temperature of the Mars troposphere is 228 K, in the troposphere, the temperature decreases by an average of 2.5 degrees per kilometer, and the above-mentioned tropopause (30 km) of the stratosphere has an almost constant temperature of 144 K.
According to researchers from the center named after Karl Sagan, in recent decades, the warming process has been going on. Other specialists believe that such conclusions are still early.
There are information that in the past the atmosphere could be more dense, and the climate was warm and wet, and liquid water existed on the surface of Mars and rained. The proof of this hypothesis is the analysis of the ALH 84001 meteorite, which showed that about 4 billion years ago, the temperature of Mars was 18 ± 4 ° C.
Dust vortices
Dusty vortices, photographed by Marshow "Opponuniti" on May 15, 2005. The numbers in the lower left corner displays the time in seconds from the moment of the first frame.
Starting from the 1970s. Within the framework of the Viking program, and numerous dust whirlwinds were recorded by the Viking Program and other devices. These are air swear arising from the surface of the planet and lifting a large amount of sand and dust into the air. The vortices are often observed on Earth (in English-speaking countries they are called dust demons - Dust Devil), but they can achieve much larger in Mars: 10 times higher and 50 times wider terrestrial. In March 2005, the whirlwind cleared the solar panels at the Spirit Marshode.
Surface
Two thirds of the surface of Mars occupy bright areas that called the continents, about a third of the dark areas, called the seas. The sea is concentrated, mainly in the southern hemisphere of the planet, between 10 and 40 ° latitude. In the northern hemisphere there are only two large seas - Acidali and Big Syr.
The nature of the dark sites is still subject to disputes. They persist, despite the fact that dust storms are raging on Mars. At one time, it served as an argument in favor of the assumption that dark areas are covered with vegetation. Now it is believed that these are simply plots from which, by virtue of their relief, dust blows easily. Large-scale snapshots show that in fact, dark areas consist of groups of dark strips and stains associated with crater, hills and other obstacles to the wind path. Seasonal and long-term changes in their size and forms are associated, apparently, with a change in the ratio of surface areas covered with light and dark substances.
The hemisphere of Mars is quite varying by the nature of the surface. In the southern hemisphere, the surface is 1-2 km above the middle level and densely dodged with craters. This part of Mars resembles lunar continents. In the north, most of the surface is below the average level, there are few craters here, and the main part occupy relatively smooth plains, which were probably formed as a result of the flooding of lava and erosion. Such a difference of hemispheres remains the subject of discussion. The boundary between hemispheres should be approximately a large circle inclined by 30 ° to the equator. The boundary is wide and improper and forms a slope towards the north. Along it, there are the most eroded sections of the Martian surface.
Two alternative hypotheses explaining the hemispheres asymmetry. According to one of them, in the early geological stage, lithospheric plates "Cut" (perhaps, by chance) in one hemisphere, like the Pangea continent on Earth, and then "frozen" in this position. Another hypothesis involves a collision of Mars with a cosmic body size with Pluto.
Topographic map of Mars, according to Mars Global Surveyor, 1999
A large number of craters in the southern hemisphere assumes that the surface here is ancient - 3-4 billion years. Several types of crater are distinguished: large crater with flat bottom, smaller and young cup-shaped craters, similar to lunar, crater, surrounded with shaft, and elevated crater. The last two types are unique to Mars - the crater with the shaft were formed there, where liquid emissions flowed on the surface, and the elevated crater was formed there, where the cruciform emissions coverly protected the surface from the wind erosion. The largest detail of shock origin is Plain Allad (about 2,100 km in the diameter).
In the area of \u200b\u200bthe chaotic landscape near the border, the hemispheres surface experienced faults and compression of large areas, which sometimes followed erosion (due to landslides or catastrophic release of groundwater), as well as flooding with liquid lava. Chaotic landscapes are often located at the source of large channels cut through water. The most acceptable hypothesis of their joint formation is the sudden melting of subsurface ice.
Mariner Valley on Mars
In the northern hemisphere, in addition to extensive volcanic plains, there are two areas of large volcanoes - Farsida and Elisia. Farsida - extensive volcanic plain with a length of 2000 km, reaching a height of 10 km above the middle level. There are three large panel volcanoes on it - Mount Arcia, Pavlin Mountain and Asshriya Mountain. At the edge of the Farsida is the highest on Mars and in the Solar System of Mount Olympus. Olympus reaches 27 km of height in relation to its base and 25 km relative to the average level of the surface of Mars, and covers an area of \u200b\u200b550 km with a diameter, surrounded by cliffs, places reaching 7 km of height. Olimpa is 10 times higher than the volume of the largest volcano of the Mauna Kea Earth. There are also several less large volcanoes. Elysius - elevation up to six kilometers above the middle level, with three volcanoes - dome chaps, Mount Alias \u200b\u200band Dome Albor.
According to other data (Faure and Mensing, 2007), the height of Olympus is 21,287 meters above the zero level and 18 kilometers above the surrounding area, and the base diameter is approximately 600 km. The base covers an area of \u200b\u200b282600 km2. Caldera (deepening in the center of the volcano) has a width of 70 km and a depth of 3 km.
Farcide hill is also crossed by a variety of tectonic faults, often very complex and extended. The largest of them - Mariner Valley - stretches in a latitudinal direction by almost 4000 km (quarter of the planet circle), reaching the width 600 and depth of 7-10 km; By size, this spill is comparable to an East African rift on Earth. In its steep slopes, the largest landslide in the solar system occur. Mariner Valley are the largest famous canyon in the solar system. The canyon, which was opened by the Mariner-9 spacecraft in 1971, could take the entire territory of the United States, from the ocean to the ocean.
Panorama of Crater Victoria, shot by the "Opportunity" by the Marshow. She was filmed in three weeks, from October 16 to November 6, 2006.
Panorama of the surface of Mars in the Husband Hill area, shot by the «Spirit November 23-28 2005».
Loda and polar caps
Northern Polar Cap in the summer, photo Mars Global Serversiore. Long wide spill, disseminating cap on the left - Northern Rift
The appearance of Mars varies greatly depending on the time of year. First of all, the changes in the polar hats are striking. They grow up and decrease, creating seasonal phenomena in the atmosphere and on the surface of Mars. The South Polar Cap can reach the latitude of 50 °, the northern - also 50 °. The diameter of the constant part of the northern polar cap is 1000 km. As the spring, the polar hat in one of the hemispheres retreats, the details of the surface of the planet begin to darken.
Polar caps consist of two components: seasonal - carbon dioxide and century-old - water ice. According to the data from the Mars Satellite Express, the thickness of the caps can be from 1 m to 3.7 km. The Mars Odyssey apparatus found on the southern polar cap of Mars acting geasers. According to NASA experts, the jet of carbon dioxide with spring warming is pulled up at a large height, carrying with them dust and sand.
Photos of Mars, on which you can see dust storm. June - September 2001
Spring melting of polar caps leads to a sharp increase in the pressure of the atmosphere and the movement of large gas masses in the opposite hemisphere. The speed of the winds at the same time is 10-40 m / s, sometimes up to 100 m / s. The wind raises a large amount of dust from the surface, which leads to dust storms. Strong dust storms almost completely hide the surface of the planet. Dust storms have a noticeable effect on the temperature distribution in the atmosphere of Mars.
In 1784, Astronomer W. Herschel drew attention to seasonal changes in the size of polar caps, by analogy with melting and the intention of ice in the earthly polar regions. In the 1860s The French astronomer E. Lie watched the wave of darkening around the melting spring polar cap, which was then interpreted by a hypothesis about spreading melt waters and growing vegetation. Spectrometric measurements that were conducted at the beginning of the XX century. In the Observatory of Lovello in Flagstaff V. Slifer, however, did not show the presence of the chlorophyll line - the green pigment of earthly plants.
According to photographs, Mariner-7 managed to determine that the polar caps have a thickness of several meters, and the measured temperature of 115 K (-158 ° C) confirmed the possibility that it consists of frozen carbon dioxide - "dry ice".
The elevation, which was named after Mitchell Mountains, located near the southern Pole of Mars, when melting the polar cap looks like a white island, because in the mountains, the glaciers are melted later, including on Earth.
The data of the Martian reconnaissance satellite apparatus allowed detecting a significant layer of ice under stony orals. The glacier is hundreds of meters in thousands of square kilometers, and its further study is able to provide information about the history of the Martian climate.
River beds and other features
On Mars there are many geological formations resembling aquatic erosion, in particular, dried river beds. According to one of the hypotheses, these channels could be formed as a result of short-term catastrophic events and are not proof of the long existence of a river system. However, the latest data suggests that the rivers flowed during geologically significant time intervals. In particular, inverted channels were found (that is, the beds raised above the surrounding area). On Earth, such formations are formed due to the long-term accumulation of dense bottom sediments, followed by drying and weathering around the surrounding rocks. In addition, there is evidence of the bias of the bed in the river delta with a gradual lift of the surface.
In the south-western hemisphere, in the crater Eberswald, a delta of the river area of \u200b\u200babout 115 km2 was found. The river lasted the Delta had a length of more than 60 km.
The data of NASA "Spirit" and "Opportunities" indicate also the presence of water in the past (minerals found, which could be formed only as a result of prolonged exposure to water). The Phoenix apparatus discovered ice deposits directly in the soil.
In addition, dark bands were found on the slopes of hills, indicating the appearance of liquid salt water on the surface in our time. They appear shortly after the onset of the summer period and disappear by winter, "streamlined" various obstacles, merge and diverge. "It is difficult to imagine that such structures could not be formed from fluid flows, but from something else," said NASA officer Richard Zurak.
There are several unusual deep wells on the volcanic elevation of the Farcide. Judging by the image of the apparatus "Martian intelligence satellite", made in 2007, one of them has a diameter of 150 meters, and the illuminated part of the wall goes deep into at least 178 meters. An hypothesis of the volcanic origin of these formations has been expressed.
Priming
The elemental composition of the surface layer of the Martian soil according to the data of the landing devices of the neodynaks in different places. The main component of the soil - silica (20-25%) containing an admixture of hydrates of iron oxides (up to 15%), which give the soil reddish. There are significant impurities of sulfur compounds, calcium, aluminum, magnesium, sodium (percent units for each).
According to the NASA probe "Phoenix" (landing for Mars on May 25, 2008), the pH ratio and some other parameters of the Martian soil are close to the earth, and they could theoretically be grown by plants. "In fact, we found that the soil on Mars meets the requirements, and also contains the necessary elements for the occurrence and maintenance of life both in the past and in the present and future," said the leading chemical researcher Sam Kunyivs. Also, according to him, this alkaline type of soil can meet at the "backyard", and it is quite suitable for growing asparagus.
At the landing site of the apparatus in the ground there is also a significant amount of water ice. The orbital probe "Mars Odyssey" also found that under the surface of the Red Planet there are deposits of water ice. Later, this assumption was confirmed by other devices, but the final question about the presence of water on Mars was resolved in 2008, when the "Phoenix" probe, nursing near the North Pole of the Planet, received water from Martian soil.
Geology and internal structure
In the past on Mars, how and on the ground moved lithospheric plates. This is confirmed by the peculiarities of Mars magnetic field, in places the location of some volcanoes, for example, in the phaside province, as well as the form of the Mariner Valley. The current state of affairs, when volcanoes can exist much longer than a long time than on Earth and to achieve gigantic sizes says that now this movement is rather absent. In favor of this, the fact that the shield volcanoes grow as a result of repeated eruptions from the same across for a long time. On Earth, due to the movement of lithospheric plates, volcanic points constantly changed their position, which limited the growth of shield volcanoes, and may not allow them to achieve heights, as on Mars. On the other hand, the difference in the maximum height of volcanoes can be explained by the fact that due to the smaller gravity in Mars, it is possible to build higher structures that would not have collapsed under their own weight.
Comparison of the structure of Mars and other planets of the earth group
Modern models of the internal structure of Mars suggest that Mars consists of a bark with a medium thickness of 50 km (and maximum up to 130 km), a silicate mantle with a thickness of 1800 km and a nucleus with a radius of 1480 km. The density in the center of the planet should reach 8.5 g / cm2. The kernel is partially liquid and consists mainly of iron with an admixture of 14-17% (by mass) of sulfur, and the content of light elements is twice as high as in the Earth's kernel. According to modern estimates, the formation of the nucleus coincided with a period of early volcanism and continued about a billion years. Approximately the same time took partial melting of mantle silicates. Due to less gravity on Mars, the pressure range in Mars's mantle is much smaller than on Earth, which means there are fewer phase transitions. It is assumed that the olivine phase transition to the spinel modification begins at quite large depths - 800 km (400 km on Earth). The nature of the relief and other signs suggest the presence of an asthenosphere consisting of areas of partially molten substance. For some areas of Mars, a detailed geological map is compiled.
According to observations from the orbit and analyzing the collection of Martian meteorites, the surface of Mars is mainly from the basalt. There are some reason to assume that on the part of the Martian surface, the material is more quartz-containing than an ordinary basalt and may be similar to theezite stones on Earth. However, the same observations can be interpreted in favor of the presence of quartz glass. A significant part of the deeper layer consists of a grainy dust of iron oxide.
Magnetic field of Mars
Mars had a weak magnetic field.
According to the indications of MARS-2 and MARS-3 stations, the magnetic field voltage at the equator is about 60 gamps, on a pole 120 gamm, which is 500 times weaker than the earth. According to AMC MARS-5, the tension of the magnetic field at the equator was 64 gamma, and the magnetic moment - 2.4 · 1022 Ersted · cm2.
The magnetic field of Mars is extremely unstable, at various points of the planet, its tension may differ from 1.5 to 2 times, and the magnetic poles do not coincide with the physical. This suggests that the Mars's iron core is in comparative immobility towards its crust, that is, the mechanism of Planetary Dynamo, responsible for the magnetic field of the Earth, does not work on Mars. Although there are no steady non-plane magnetic field on Mars, the observations showed that the parts of the planetary cortex are namagged and that the change of magnetic poles of these parts in the past was observed. The magnetization of these parts was similar to strip magnetic anomalies in the ocean.
According to one theory published in 1999 and rechecked in 2005 (with the help of an unmanned station Mars Global Servetor), these bands demonstrate to the plateonics of plates 4 billion years ago before the Dynamo Machine Planet stopped performing its function, which caused a sharp weakening magnetic field. The reasons for such a sharp weakening are unclear. There is an assumption that the functioning of the dynamo machine is 4 meters. It is explained in the presence of an asteroid, which rotated at a distance of 50-75 thousand kilometers around Mars and caused instability in his core. The asteroid dropped to Rosh's limit and collapsed. Nevertheless, this explanation itself contains unclear moments, and disputes in the scientific community.
Geological History
Global mosaic from 102 images of orbiter Viking-1 dated February 22, 1980.
Perhaps, in a distant past, as a result of a collision with a large celestial body, the nucleus rotation was stopped, as well as the loss of the main volume of the atmosphere. It is believed that the loss of the magnetic field occurred about 4 billion years ago. Due to the weakness of the magnetic field, the solar wind penetrates into the atmosphere of Mars, and many of the photochemical reactions under the action of solar radiation, which occur on the Earth in the ionosphere and above, can be observed on Mars almost at its very surface.
The geological history of Mars concludes three of the following epochs:
Noyachian epoch (named after the "Nochai Earth", district of Mars): the formation of the most old surface of Mars the most old preserved to this day. Continued in the period of 4.5 billion - 3.5 billion years ago. In this era, the surface was chilled by numerous shock crater. The plateau of the phaside province was probably formed during this period with intense water flow later.
Hesperian Era: from 3.5 billion years ago to 2.9 - 3.3 billion years ago. This era is marked by the formation of huge lava fields.
Amazonian era (named after the Amazon Plain on Mars): 2.9-3.3 billion years ago to the present day. The areas formed in this era have very little meteoric craters, but in all the rest they completely differ. Mount Olympus formed during this period. At this time, lava flows were bottled in other parts of Mars.
Mars satellites
Natural satellites Mars are Phobos and Dimimos. Both are open by American astronomer Asaf Hall in 1877. Phobos and Demimos have an irregular shape and very small sizes. According to one of the hypotheses, they may be trapped by the gravitational field of Mars asteroids like (5261) Eureka from the Trojan group of asteroids. The satellites are named after the characters accompanying God Ares (that is, Marsa), Fobos and Deimos, personifying fear and horror, who helped God of war in battles.
Both satellites rotate around their axes with the same period as around Mars, so always turning to the planet with the same side. The tidal effect of Mars gradually slows down the movement of phobos, and will eventually lead to a fall of the satellite on Mars (when maintaining the current trend), or to its decay. On the contrary, the Dimim is removed from Mars.
Both satellites have a form approaching the three-axis ellipsoid, Phobos (26.6x22.2x18.6 km) is somewhat larger than Daimos (15x12.2x10.4 km). The Daimos surface looks much smoother due to the fact that most of the craters are covered with a fine-grained substance. Obviously, on Phobos, closer to the planet and more massive, the substance discharged during the blows of meteorites, or applied repeated blows on the surface, or fell on Mars, while on Deamos it remained in orbit around the satellite, gradually precipitated and Hiding irregularity of relief.
Life on Mars
The popular idea that Mars is inhabited by intelligent Martians, widely spread at the end of the XIX century.
Skiaparelli observations of the so-called channels, combined with the book of Percival Lowell on the same topic made a popular idea about the planet, whose climate became all land, which was dying and in which an ancient civilization existed, producing irrigation work.
Other numerous observations and announcements of famous persons gave rise around this topic the so-called "Martian fever" ("Mars Fever"). In 1899, during the study of atmospheric interference in a radio signal, using receivers in the Colorado Observatory, the inventor of Nikola Tesla observed a repeating signal. Then he suggested that it could be a radio signal from other planets, for example, Mars. In an interview with 1901, Tesla said he had the idea that interference could be caused artificially. Although he could not decipher their meaning, it was impossible for him that they arose completely by chance. In his opinion, it was a greeting of one planet another.
Tesla Theory caused hot support for the famous British Physics and Physics and Physics of William Thomson (Lord Kelvin), who, visiting the United States in 1902, said that in his opinion Tesla caught the Martian signal sent to the United States. But then Celvin began to decisively deny this statement before left America: "In fact, I said that the inhabitants of Mars, if they exist, can undoubtedly see New York, in particular light from electricity."
To date, the condition for the development and maintenance of life on the planet is the presence of liquid water on its surface. There is also a requirement that the orbit of the planet is in the so-called inhabited zonewhich starts for the solar system begins behind the Venus and ends with a large half-axis orbit of Mars. During the perihelion, Mars is inside this zone, however, a thin atmosphere, with low pressure prevents the appearance of liquid water at a significant area for a long period. Recent evidence suggests that any water on the surface of Mars is too salty and acidic to maintain a constant earthly-like life.
The lack of magnetosphere and the extremely thin atmosphere of Mars are also a problem for maintaining life. On the surface of the planet there is a very weak movement of heat fluxes, it is poorly isolated from bombing by particles of solar wind, in addition, during heating, water instantly evaporates, bypassing the liquid state due to low pressure. Mars is also on the verge of t. "Geological death." The end of volcanic activity apparently stopped the cycle of minerals and chemical elements Between the surface and the inside of the planet.
Certificates suggest that the planet has previously been much more predisposed for the presence of life than now. However, today the remnants of organisms are not found on it. According to the Viking program, implemented in the mid-1970s, a series of experiments were conducted to detect microorganisms in Martian soil. It gave positive results, for example, a temporary increase in the selection of CO2 when placing the soil particles into water and a nutrient medium. However, then this testimony of life on Mars was challenged by some scientists [who?]. This led to their long-term disputes with scientists from Nasa Hilbert Levin, who claimed that Viking found life. After the revaluation of the "Viking" data in the light of modern scientific knowledge of extremophilas, it was found that the experiments were not perfect enough to detect these forms of life. Moreover, these tests could even kill organisms, even if they were kept in samples. The tests conducted under the Phoenix program showed that the soil has a very alkaline pH factor and contains magnesium, sodium, potassium and chloride. Nutrients in the soil are sufficient to maintain life, but life forms should be protected from intensive ultraviolet light.
Interestingly, education was found in some meteorites of Martian origin, in shape resembling the simplest bacteria, although inferior to the smallest earthly organisms in size. One of these meteorites is the ALH 84001 found in Antarctica in 1984.
According to the results of observations from the Earth and the data of the Mars Express spacecraft in the atmosphere of Mars, methane was found. Under Mars, this gas decomposes quite quickly, so there must be a permanent source of its replenishment. Such a source can be either geological activity (but the active volcanoes on Mars were not detected), or the vital activity of bacteria.
Astronomical observations from the surface of Mars
After planting automatic devices, the surface of Mars appeared the ability to lead astronomical observations directly from the surface of the planet. Due to the astronomical position of Mars in the solar system, the characteristics of the atmosphere, the period of the appeal of Mars and its satellites, the picture of the night sky of Mars (and astronomical phenomena observed from the planet) differs from the earth and is largely represented by an unusual and interesting.
Sky color on Mars
During the sunrise and sunset, the Martian sky in the zenith has a reddish-pink color, and in close proximity to the Disk of the Sun - from the blue to violet, which is exactly the opposite picture of the earth's dawn.
At noon, the sky of Marsa Yelah-orange. The reason for such differences from the color gamut of the earth's sky is the properties of a thin, rareered, containing suspended dust of the atmosphere of Mars. On Mars Rayleigh scattering rays (which is on earth and causes the blue sky) plays a minor role, its effect is weak. Presumably, the yellow-orange painting of the sky is also caused by the presence of 1% magnetite in dust particles constantly weighted in the Martian atmosphere and raised by seasonal dust storms. Twilight start long before the sunrise and last long after it comes. Sometimes the color of the Martian sky acquires a purple shade as a result of scattering of light on water ice microparticles in the clouds (the latter is a rather rare phenomenon).
Sun and planets
The angular size of the sun, observed from Mars, is less visible from the ground and is 2/3 from the last. Mercury from Mars will be practically unavailable for observations by the unarmed eye due to the extreme intimacy to the Sun. The brightest planet in the sky of Mars is Venus, in second place - Jupiter (his four largest satellites can be observed without a telescope), on the third - Earth.
The land towards Mars is the inner planet, as well as Venus for the Earth. Accordingly, from Mars Earth is observed as a morning or evening star, ascending before dawn or visible in the evening sky after sunset.
The maximum elongation of the Earth in the sky of Mars will be 38 degrees. For the unarmed Eye, the Earth will be visible as a bright (maximum visible star value about -2.5) a greenish star, which is easily distinguishable with a yellowish and more dull (about 0.9) the moon asterisk. In the telescope, both objects will show the same phases. The appeal of the moon around the Earth will be observed from Mars as follows: At the maximum angular removal of the moon from the ground, the unarmed eye will easily divide the moon and the ground: in a week "stars" of the moon and the earth are somewhat in the inseparable eye of a single star, after another week the moon will be visible again at the maximum The distance, but on the other side of the earth. Periodically, the observer on Mars will be able to see the passage (transit) of the Moon on the Earth disk or, on the contrary, the cover of the Moon to the Earth's disc. The maximum visible removal of the moon from the Earth (and their visible brightness) when observed from Mars will change significantly depending on the mutual position of the Earth and Mars, and, accordingly, the distances between the planets. In the opposition's era, it will be about 17 minutes of arc, at the maximum removal of the Earth and Mars - 3.5 minutes of arc. Earth, like other planets, will be observed in the zodiac constellation strip. Astronomer on Mars will also be able to observe the passage of the Earth on the Disk of the Sun, the nearest will occur on November 10, 2084.
Satellites - Phobos and Dimimos
The passage of phobos on the sun disk. Snapshots "Opportunities"
Phobos, when observed from the surface of Mars, has a visible diameter of about 1/3 from the moon disk on the earth's sky and the visible star magnitude of order -9 (approximately as the moon in the first quarter phase). Phobos goes back in the West and sits in the east to fall again after 11 hours, so twice a day crossing the sky of Mars. The movement of this fast moon over the sky will be easily noticeable overnight, just like the phase change. The naked eye will distinguish the largest detail of the relief of phobos - the crater of stalking. Daimos dates back to the East and comes in the West, looks like a bright star without a noticeable visible disc, a star magnitude around -5 (a little brighter Venus on the earthly sky), slowly crossing the sky for 2.7 Martian days. Both satellites can be observed at the night sky at the same time, in this case phobos will move towards Dimimos.
Brightness and phobos, and action is sufficient so that the items on the surface of Mars at night have discarded clear shadows. Both satellites have a relatively small tilt of the orbit to the Equator of Mars, which eliminates their observation in the high northern and southern latitudes of the planets: So, Phobos never goes over the horizon north of 70.4 ° C. sh. or south of 70.4 ° sh.; For Deimos, these values \u200b\u200bare 82.7 ° C. sh. and 82.7 ° sh. On Mars, the eclipse of Phobos and Deimos may be observed at their entrance to the shadow of Mars, as well as the eclipse of the Sun, which only ring-shaped due to the small angular size of phobos compared to the Sun disk.
Celestial sphere
The North Pole on Mars, due to the tilt of the planet's axis, is in the winned constellation (equatorial coordinates: direct climbing 21H 10M 42S, decline + 52 ° 53.0? And not marked with a bright star: the nearest to the pole - the dull star of the sixth size BD +52 2880 (others Its notation - HR 8106, HD 201834, SAO 33185). The South Pole of the world (coordinates 9H 10M 42S and -52 ° 53.0) is in a pair of degrees from the star Cappa of sails (visible stars 2.5) - it is in principle , can be considered southern Polar star Mars.
Zodiacal constellations of Martian Ecliptic are similar to those observed from the Earth, with one difference: when observing the annual movement of the Sun among the constellations, it (like other planets, including land), coming out of the eastern part of the constellation of fish, will take place within 6 days across the northern part of China's constellation before how to join the western part of the fish again.
History of studying Marsa
The study of Mars began a long time ago, another 3.5 thousand years ago, in ancient Egypt. The first detailed reports on the situation of Mars were compiled by Babylonian astronomers who developed a number. mathematical methods To predict the position of the planet. Using the data of Egyptians and Babylonians, the ancient Greek (Hellenistic) philosophers and astronomers developed a detailed geocentric model to explain the movement of the planets. After several centuries, Indian and Islamic astronomers were estimated the size of Mars and the distance to it from the ground. In the XVI century, Nikolai Copernicus proposed a heliocentric model to describe the solar system with circular planetary orbits. Its results were revised by Johann Kepler, which introduced a more accurate elliptical orbit of Mars coinciding with the observed.
In 1659, Francesco Fountain, considering Mars to the telescope, made the first drawing of the planet. He depicted a black spot in the center of a clearly defined sphere.
In 1660, two polar caps added by Jean Dominique Cassini added to the Black Spot.
In 1888, Giovanni Skiaparelli, who studied in Russia, gave the first names to individual details of the surface: the sea of \u200b\u200bAphrodite, Eritrea, Adriatic, Kimmerian; Lakes of the Sun, Lunar and Phoenix.
The flourishing of telescopic observations of Mars came to end XIX. - middle of the XX century. In many ways, it is due to public interest and well-known scientific disputes around the observed Martian channels. Among the astronomers of the Premocking Era, who conducted the telescopic observations of Mars during this period, the most famous Skiaparelli, Percival Lovell, Slitifer, Antoniadi, Barnard, Zharry-Daughte, L. Eddie, Tykhov, Vocolator. It was them that the foundations were laid and the first was drawn up detailed maps The surfaces of Mars - although they turned out to be almost completely incorrect after flights to Marsa automatic probes.
Colonization of Mars
Estimated form of Mars after terravertation
Relatively close to earthly natural conditions Several facilitate the execution of this task. In particular, there are places in which natural conditions are similar to Martian. Extremely low temperatures in the Arctic and Antarctica are comparable even with the lowest temperatures on Mars, and on the Equator of Mars in the summer months it is also warm (+20 ° C), as on earth. Also on Earth there are deserts similar to the form with the Martian landscape.
But between the earth and Mars there are significant differences. In particular, the Mars magnetic field is weaker than 800 times. Together with the rescued (hundreds of times in comparison with the earth), this increases the amount of ionizing radiation achieving its surface. The measurements carried out by the American unmanned apparatus The Mars Odyssey showed that the radiation background in the orbit of Mars is 2.2 times higher than the radiation background on the international space station. The average dose amounted to about 220 millions per day (2.2 billion per day or 0.8 Gray per year). The volume of irradiation obtained as a result of the stay in a background for three years is approaching the established security limits for astronauts. On the surface of Mars, the radiation background is slightly lower and the dose is 0.2-0.3 Gy per year, changing significantly depending on the terrain, height and local magnetic fields.
The chemical composition of the minerals common on Mars is more diverse than others heavenly Tel Near the ground. According to the 4Frontiers corporation, they are enough to supply not only Mars itself, but also the moon, land and asteroid belt.
Flight time from Earth to Mars (with current technologies) is 259 days half-cell and 70 - on Parabola. To communicate with potential colonies, radio communication can be used, which has a delay of 3-4 minutes in each direction during the maximum rapprochement of the planets (which is repeated every 780 days) and about 20 minutes. With maximum removal of the planets; See Configuration (Astronomy).
To date, no practical steps for the colonization of Mars are undertaken, however, the development of colonization, for example, a centenary project spaceshipDevelopment of a residential module for staying on the Deep Space Habitat planet.
Today, not only sciences in their stories, but also real scientists, businessmen, politicians speak about flights for Mars and its possible colonization. Probe and mercursors gave answers to geology features. However, for manned missions should be sorted out if Mars has an atmosphere and what it is in its structure.
General
Mars has its own atmosphere, but it is only 1% of the earth. Like Venus, consists mainly of carbon dioxide, but again, much thinner. The relatively dense layer is 100 km (for comparison, the Earth is 500 to 1000 km by different estimates). Because of this, there is no protection against solar radiation, and the temperature regime is practically not regulated. The air on Mars is in the usual understanding of us.
Scientists have established an accurate composition:
- Carbon dioxide - 96%.
- Argon - 2.1%.
- Nitrogen - 1.9%.
In 2003, methane was found. The discovery spurred interest in the Red Planet, many countries launched research programs that led to conversations about flights and colonization.
Because of the low density, the temperature regime is not regulated, so the differences are on average 100 0 C. In the daytime, there are enough comfortable conditions +30 0 s, and at night the surface temperature drops to -80 0 C. Pressure is 0.6 kPa (1 / 110 from the earth's figure). On our planet, such conditions are found at an altitude of 35 km. This is the main danger to a person without protection - it will be killed by no temperature or gases, but pressure.
The surface constantly present dust. Due to the small gravity of the clouds rise to 50 km. Strong temperature differences lead to winds with gusts up to 100 m / s, so dust storms on Mars are common. It is not a serious threat due to the small concentration of particles in the air masses.
What layers is the atmosphere of Mars?
The strength of gravity is less terrestrial, therefore Marsa atmosphere is not so clearly divided into layers of density and pressure. The homogeneous composition is preserved to 11 km, then the atmosphere begins to be divided into layers. Above 100 km density decreases to minimum values.
- Troposphere - up to 20 km.
- Stratomezosphere - up to 100 km.
- Thermosphere is up to 200 km.
- Ionosphere - up to 500 km.
IN upper atmosphere There are lung gases - hydrogen, carbon. Oxygen accumulates in these layers. Separate particles of atomic hydrogen are distributed to a distance of up to 20,000 km, forming a hydrogen crown. Clear separation between extreme regions and space space not.
Upper atmosphere
At the mark of more than 20-30 km, there is a thermosphere - upper areas. The composition remains stable to a height of 200 km. There is a high content of atomic oxygen. The temperature is low enough - up to 200-300 K (from -70 to -200 0 s). Next is the ionosphere, in which the ions react with neutral elements.
Lower atmosphere
Depending on the time of year, the border of this layer changes, and this zone is called the tropopause. Next extends the stratomezosphere, the temperature of which on average is -133 0 S. On Earth, there is ozone that protects against cosmic radiation. On Mars, it accumulates at an altitude of 50-60 km and then practically absent.
The composition of the atmosphere
The earth's atmosphere consists of nitrogen (78%) and oxygen (20%), in small quantities there are argon, carbon dioxide, methane, etc. Such conditions are considered optimal for life. The composition of the air on Mars is significantly different. The main element of the Martian atmosphere is carbon dioxide - about 95%. Nitrogen accounts for 3%, and on argon 1.6%. The total amount of oxygen is not more than 0.14%.
Such a composition was formed due to the weak attraction of the red planet. The most stable turned out to be heavy carbon dioxide, which is constantly updated as a result of volcanic activity. Light gases are dissipated in space, due to the low force of attraction and absence of a magnetic field. Nitrogen is held by gravitation in the form of a duptomic molecule, but is split under the influence of radiation, and the form of single atoms flies into space.
A similar situation with oxygen, but in the upper layers it reacts with carbon and hydrogen. However, scientists do not fully understand the features of reactions. According to calculations, the amount of carbon monoxide gas should be greater, but in the end it is oxidized to CO2 carbon dioxide and falls to the surface. Separately, O2 molecular oxygen appears only after the chemical decay of carbon dioxide and water in the upper layers under the influence of photons. It belongs to non-condensing on Mars substances.
Scientists believe that millions of years ago the amount of oxygen was comparable to earth - 15-20%. It is not yet known exactly why conditions have changed. However, individual atoms are not so actively destroyed, and because of the greater weight, it even accumulates. To some extent there is a reverse process.
Rest important elements:
- Ozone is practically absent, there is one area of \u200b\u200bcluster 30-60 km from the surface.
- Water is 100-200 times less content than in the dry of the land region.
- Methane is observed emissions of an unknown nature, and the most discussed substance for Mars.
Methane on Earth belongs to biogenic substances, so it can potentially be associated with an organic. The nature of the appearance and rapid destruction is not yet explained, so scientists are looking for answers to these questions.
What happened to the atmosphere of Mars in the past?
Throughout millions of years, the existence of the planet atmosphere varies in composition and structure. As a result of research, evidence appeared that in the past, liquid oceans existed on the surface. However, now water remained in small quantities in the form of a pair or ice.
The reasons for the disappearance of the fluid:
- Low atmospheric pressure is not able to maintain water in a liquid state for a long time, as it happens on Earth.
- Gravity is not sufficient strong to hold the clouds of steam.
- Due to the lack of a magnetic field, the substance is carried out by particles of solar wind into space.
- With significant temperature drops, water can only be stored in solid state.
In other words, the atmosphere of Mars is not dense enough to preserve water in the form of a liquid, and the small force of attraction is not able to keep hydrogen and oxygen.
According to experts, favorable conditions for living on a red planet could form about 4 billion years ago. Perhaps at that time there was life.
Call the following causes of destruction:
- The lack of protection against the radiation of the Sun and gradually depleting the atmosphere throughout the millions of years.
- A collision with a meteorite or other cosmic body, instantly destroyed the atmosphere.
The first reason on this moment So far probably, since the traces of the global catastrophe have not yet been detected. Such conclusions managed to make thanks to the study of the autonomous Curiosity station. The rover set the accurate composition of the air.
The ancient atmosphere of Mars contained a lot of oxygen
Today, scientists have practically no doubt that there was water before the red planet. On numerous types of ocean outlines. Visual observations are confirmed by specific studies. Marsoises took primer tests in the valleys of the former seas and rivers, and the chemical composition confirmed the initial assumptions.
In the present conditions, any liquid water on the surface of the planet will instantly evaporate, because the pressure is too low. However, if oceans and lakes existed in ancient times, then the conditions were different. One of the assumptions is another composition with a fraction of oxygen about 15-20%, as well as increased shares of nitrogen and argon. In this form, Mars becomes almost identical to our native planet - with liquid water, oxygen and nitrogen.
Other scientists suggest the existence of a full-fledged magnetic field capable of protecting from solar wind. Its power is comparable to earthly, and this is another factor that speaks in favor of the presence of conditions for the origin and development of life.
Causes of exhaustion of the atmosphere
The vertex of development falls on the Gherryi Era (3.5-2.5 billion years ago). On the plain was the salt ocean, comparable in size with the northern ice ocean. The temperature at the surface reached 40-50 0 C, and the pressure was about 1 atm. A high probability of the existence of living organisms at that time. However, the period of "prosperity" was not long enough to arise complex and the more reasonable life.
One of the main reasons is the small size of the planet. Mars less land, so gravity and magnetic field are weaker. As a result, the sunny wind actively knocked out the particles and literally cut off the shell layer behind the layer. The composition of the atmosphere began to change for 1 billion years, after which the climatic changes have become catastrophic. Reducing pressure led to evaporation of fluid and temperature drops.
Since Mars is farther from the Sun than the Earth, he can take the position in the sky opposite to Sun-CSU, then he is visible all night. This position of the planet is naked confronting. Marsa is repeated every two years and two months. Since the orbit of Mars is stretched more terrestrial, then during the oppositions of the distance between the Mar-Som and the Earth can be different. Once in 15 or 17 years old, there is a great confrontation when the distance between Earth and Mars is minimal and amounts to 55 million km.
Channels on Mars
On the photos of Mars, made from the Space Telecom-Pa Hubble, the characteristic features of the planet are clearly visible. On the red background of the Martian deserts clearly visible to the Lubovato-green seas and a bright white polar hat. Famous channels The picture is not visible. With such an increase, they are really not visible. After large-scale pictures of Mars were obtained, the mystery of the Mar Siana channels was finally resolved: the channels predict the optical illusion.
Of great interest was the question of the possibility of land life on Mars. Conducted in 1976 on the American Canine AMS "Viking" studies gave, apparently, the windows-auctive negative result. No trace of life on Mars was found.
However, and currently comes a revolving discussion about this. Both sides, both the sides, and opponents of life on Mars, lead the argumen-you, who cannot disprove their opponents. For the solution of this issue, it is simply not enough experimental data. It remains only to expect when the MARSA has been implemented and the plates will give material confirming or refuting the existence of life on Mars in our time or in a distant past. Material from site.
Mars has two small satellite - Phobos (Fig. 51) and Dimimos (Fig. 52). Their size of 18 × 22 and 10 × 16 km corresponding to it. Phobos is located from the surface of the planet on raz-standing only 6000 km and turns around it in about 7 hours, which is 3 times less than the Martian day. Dimimos is located at a distance of 20,000 km.
A number of riddles are associated with satellites. So, it is unclear about their occurrence. Most scientists believe that this is relatively recently captured asteroids. It is hard to imagine how Phobos survived after the meteorite strike, which led the crater with a diameter of 8 km on it. It is not clear why Phobos is the most black body known to us. Its reflective sociability is 3 times less than soot. Unfortunately, several flights of ka to Phobos ended in failure. The final solution to many questions like Fobosa and Mars, it is disparated to the expedition to Mars, planned on the 30s of the XXI century.
The era of colonization of Mars is approaching. NASA has planned the first expedition to the Red Planet in the summer of 2020 and it has been allocated about two billion US dollars. Against the background of this, the need to extract oxygen, which in the literal sense is vital for staying astronauts at the space station. Calculations have shown that the transportation of the main gas of the human gas from the ground is too expensive. This served as a start of reflection of scientists on the topic: Is there oxygen on Mars and, if not enough, then how to "invent" it.
How much oxygen in the atmosphere of Mars?
Ahead of events, immediately denote: Oxygen on Mars is, however, in its pure form, its amount is only 0.13%. By inhaling once Martian air, a man will perish instantly. Most of the oxygen in the red planet exists in the form of carbon dioxide, which is 95% atmosphere of Mars. The remaining part is:
- 1.6% argon;
- 3% nitrogen;
- 0.27% - water vapor residues and other gases.
Also, oxygen can exist in the form of iron oxide, which gives the planet red.
However, scientists suggest that for a very long time, gases surrounding Mars have a much larger oxygen volume, and that the only reason for which the Earth has not turned into a red planet - plants that constantly absorb carbon from carbon dioxide. It is the ecosystem that produces that air that we breathe. If Mars had been closer to the Sun (warm enough for liquid water) and large enough to hold a denser atmosphere, plants could grow there, similar topicsWhat we grow on the ground. But in the current conditions there would be special dome, heating, water and artificial light.
How can I get oxygen on Mars
Given the fact that oxygen on Mars is an atypical phenomenon, scientists solve the problem with its reproduction. 3 main ways were offered to produce air on the red planet:
- With the help of bacteria capable of absorbing air from carbon dioxide.
- The fuel cell proposed by the Moxie Massachusetts Institute.
- The use of low-temperature plasma, which is capable of using particles contained in ionized gas to extract oxygen ions.
The air on Mars is necessary for the uninterrupted work of the Research Station. Its reproduction will allow astronauts not only to breathe, but also refuel missiles to return to Earth. Given the fact that the composition of Martian air and the atmosphere differs significantly from earthly, and transportation will be very expensive, the listed methods for obtaining O2 will become a true major event in the development of new planets.
Bacteria for the creation of oxygen
And now we will describe in detail the methods of air production on Mars. The aerospace development of TechShot is engaged in a very interesting development for obtaining O2 on the Red Planet. They were assumed that oxygen can be obtained by bacteria that can absorb from carbon dioxide needed man gas. A room was created with the imitation of the atmosphere, the daytime cycle and radiation on the surface of Mars, in which the said theory was successfully confirmed.
This method of oxygen production has global significance. First, transportation of such bacteria requires smaller costs and places. Secondly, due to the relative orbits of the Earth and Mars, stock supplies will be made only once every 500 days, which makes air generation almost necessary for the colonization of the Red Planet. In turn, it is possible to offer the production of oxygen from ice or water. However, water resources are too valuable to send them to the selection of the gas required for breathing.
Moxie Experiment
The main task of the expedition is the study of the suitability of Mars for life. For this purpose, 4 planets Solar system The atomic rover CURIOSITY is sent, which needs not only to hold out on the red planet for its study, but also that the astronauts have enough oxygen on the return path. The decision found Massachusetsky technological Institute Moxie. The result of their development should be a fuel cell, which is capable of separating CO2 carbon monoxide and oxygen, which are subsequently sent to the repository. Against the background of other scientific developments, Moxie stands out that they are aimed at practical testing. Their plans include the creation on Mars an automated production workshop, which will pre-generate oxygen for arriving astronauts.
Plasma technology for oxygen production
Scientists from Portugal suggest that Mars is the most favorable place for the decomposition reaction by non-equilibrium plasma. Thermobaric parameter intervals in the red planet atmospheric field are able to cause more tangible oscillations leading to the asymmetric stretching of molecules than on Earth. This is what Mars makes a more attractive planet for experience. In addition to oxygen, the product of the plasma separation of molecules can be a ditch gas that will be used as rocket fuel. The project manager, Vasco Herra believes that for the production of 8-16 kg of air, only 150-200 W will be needed within 4 hours every twenty-five hour Martian days.
