Most of the spacecraft sent to Venus have landed on its heights. But the descent vehicle "Venera-9", which transmitted the first frames to the Center for Deep Space Communications on October 22, 1975, landed in a "low" on the mountainside. In this "pit" the accumulation of heavy gases of the Venusian atmosphere has created a kind of microclimate with temperatures above 465 degrees Celsius. The image transmitted by Venera-9 is fundamentally different from what is seen on the plateau.
First, to the very horizon, large stones of various shapes and sharply differing in size are observed. And on the left side of the panorama there are "shells", somewhat reminiscent of terrestrial snake or cowrie shells. Of course, many researchers paid attention to these "shells", but they also considered them to be stones. It did not fit into any logical framework that at such a high temperature, pressure and an atmosphere filled with chemically active compounds, something living could exist. L. V. Xanfomality in the book "The Planets Rediscovered" calls them so: "stones resembling shells, obviously with a layered structure." However, even then there were suggestions that images of formations that did not fit into the category of stones were obtained.
The well-known morphologist Professor A. A. Zubov was the first to pay attention to these strange "stones" as soon as the panorama of the image fell into his hands. But who could then agree with the scientist that structures of the same type, turned by a slot towards the descent vehicle, can be considered as living organisms? A quarter of a century ago, scientists could not accept the hypothesis of the presence of living forms on a hot planet.
In mid-1983, it was discovered that there are bacteria on Earth that can live at very high temperatures and pressures. These proteinaceous lifeforms have been found in the vents of underwater volcanoes. Scientists from Oregon have determined in the laboratory that "fiery" inhabitants from the craters of underwater volcanoes reproduce best at a temperature of 250 degrees and a pressure of 250 atmospheres. These bacteria feed on sulfur and magnesium, which are supplied in abundance by an underwater volcano. They feel good even at 400 - 450 degrees, but they cannot stand the cold and already freeze at 80 degrees.
The facts are as follows: on the left side of the panorama transmitted from Venera-9, strange "stones" of the same structure resembling cucumbers are visible. There are four of them, two in the foreground, one peeking out from behind big stone, but already real, and the fourth "shell" opened up and released some kind of mass from itself with a ball in front. Now let's see how these formations differ from the surrounding stones.
All four "shells" have the same shape and the same size, which is typical for living beings. The shells under consideration are rounded, elliptical formations, therefore, they cannot be attributed to natural crystals. Another feature, most clearly expressed in the two front "shells," is the slit, which is identical in structure, through which they are turned towards the descent vehicle. Why don't these "stones" with a layered structure lie with a gap up or down? And the structure of the gap is also the same for everyone: on the left side it is wider than on the right, and on three "shells", at least, a characteristic bend is visible, and above its wide part - a small protrusion. Similar structures, identical in structure and size, are no longer on the entire panorama to the very horizon. There are really only stones visible.
The author of the book "The Emergence of Biological Organization" G. Kastler calculated the amount of characteristic information for a bacterium, that is, perhaps, for the form of life to which the "shells" from Venus we are considering belong. According to him, the probability of a chance meeting of a repeated form for bacteria is unusually small. But taking into account all the features of the "shells" - the slit of the same morphological structure for each "shell", the possibility of turning the slot towards the descent vehicle, the presence of a kind of ball near the right end of each "shell" at the bottom - the probability that we are dealing with living beings, increases significantly. It is curious that the closer the "shells" are to the descent vehicle, the more tightly the gap is covered.
The image also has some other features that speak of the mysterious nature of the "shells" from Venus, for example, they are all located, as it were, in a primitive "dwelling" of stones. You can also clearly see the recess, bordered by flat slabs, forming a semblance of a square. However, this is a single formation, and it could have happened by chance. A careful study of the image shows that all the Venusian "shells" are not covered with gravel, unlike the stones that surround them. This is an argument in favor of the fact that they are able to move. This assumption is confirmed by the fact that all the slits of the shells face the descent vehicle. Here one can object: why, then, during the transmission of the image, all the “shells were motionless? The time during which the camera lens moved back along the panorama was eight minutes. That is, during this time the “shells” did not move. various animals or insects, frightened by the appearance of a person, seem to freeze for a while.Some animals can generally remain motionless for a long time.
No assumptions regarding the classification of "shells" can be made yet. Perhaps these are huge overgrown bacteria or the remnants of former life that once raged on the surface of the now hot planet. Confirmation of the fact of the existence of any life forms on the planets solar system will revolutionize our understanding of the universe.
The study of Venus continues. It is possible that new vehicles descending to the surface of this planet will end up not only on plateaus, but also in lowlands, where conditions are completely different and where, perhaps, there is life, which is still inexplicable to us. But we must not forget the joke invented by the earthlings themselves on behalf of aliens: how can there be life on a planet whose atmosphere contains oxygen?
There is hope that in the near future the question of the presence of life on Venus will be resolved. This requires new landings of descent vehicles in the "lowlands" of Venus. It is possible that a "shell" from Venus will ever crawl on our earthly laboratory table in a red-hot thermostat!
Earth and Venus are two very similar planets, they have approximately the same size and mass, and besides, these planets are approximately the same age - about 4.5 billion years. There is an atmosphere. And, given that Venus is closer to the Sun by forty million kilometers, the Sun heats up there not much stronger than on Earth. It would seem that there are all conditions for the emergence and development of life on Venus. And besides, according to one version, whole oceans existed there several million years ago, but for some reason this did not happen. At the moment, due to the strong greenhouse effect, hellish heat reigns on its surface - about 500 degrees Celsius. It is even hotter here than on Mercury, although it is much closer to the Sun!
Is there a hypothesis that a highly developed civilization existed on Venus? But at some point, the same global catastrophe happened there, as at the moment, according to some researchers, begins here. It is likely that the greenhouse effect will destroy all life on our planet.
She spins the other way
Venus rotates around its axis in the opposite direction to that of other planets in the solar system. It would be natural for a Venusian that the sunrise would be in the west and the sunset in the east. Astrophysicists joked that Venus, as the only planet with female name, wanted to stand out among the "men" in such a peculiar way.
The joke existed until it became clear that Uranus was also spinning in the “wrong” direction. But for what reason the planets behave in this way, scientists cannot really explain. The two main theories are a collision with a giant meteorite or some unknown processes in the cores of the planets.
A day longer than a year
Another secret is the extremely slow rotation of the planet around its axis and rather fast rotation around the Sun. As it turned out, the duration of the Venusian day is 244 Earth days. But the Venusian year is approximately 224.7 earth days. It turns out that a day on Venus lasts more than a year!
There is a hypothesis that earlier the day on Venus was much shorter. However, for unknown reasons, the rotation of the planet has slowed down. Maybe this mystery is related to the next riddle.
Venus is hollow
The images received from the satellite show this: above the South Pole of the planet in the cloud cover there is a huge black funnel - as if atmospheric vortices twist and go deep into Venus through some hole, in other words, Venus is hollow.
Naturally, no one seriously mentioned the mysterious entrance to the dungeons of Venus. But the mysterious swirling hurricanes over the planet's pole are still incomprehensible.
Is there life on Venus?
Astrophysicists are firmly convinced that on the surface, where the temperature is about 500 degrees of heat, and the pressure is 90 times higher than the earth, there is no living creature. If the temperature on Earth began to rise, as on Venus, we would all become very uncomfortable. However, you can cope with the summer heat by purchasing air conditioners in Bobruisk. Unless, of course, the existence of some organosilicon fire salamanders that feed on the red-hot lava of volcanoes is not allowed. However, life from the earth's point of view, it is quite possible to exist in the planet's atmosphere, at an altitude of about fifty kilometers. The temperature here is about 70 degrees Celsius, the pressure is almost like on Earth, and there is even water vapor. In addition, the study of Venus showed that below 50 - 70 kilometers above the surface, the ultraviolet radiation of the Sun is almost imperceptible - as if the planet is surrounded by some kind of film that absorbs this part of the spectrum. Therefore, the researchers hypothesized that microbes that absorb ultraviolet live at high altitudes, like terrestrial plants and some microorganisms.
Mysterious Venus
And although Venus has already revealed many amazing features to astronomers, nevertheless, despite the fact that it is located next to the Earth, it still keeps a lot of mysterious and mysterious things.
One of the mysteries is related to the problem of life on Venus. But since this has already been discussed, we will not touch on this problem, but will immediately move on to the next Venusian riddle - the rotation of the planet around its own axis. It, as we know, does not occur in the same way as in other planets of the solar system, including the Earth, but in the opposite direction.
Venus continues to be a mystery to researchers
This means that the cosmonaut of the future, who will be on Venus, will see an unusual picture for an earthling: the Sun here rises in the west, and sets in the east.
At one time, it was believed that such a feature is characteristic only of Venus. However, over time, it turned out that Uranus also rotates differently from the rest of its neighbors in the solar system.
But why these two planets, contrary to the rest, demonstrate such a striking originality, astronomers cannot answer, although several assumptions have been put forward to explain this phenomenon. The two main versions suggest either a collision with a giant meteorite, or some unknown processes in the cores of these planets.
Another mystery of Venus is that it rotates too slowly around its axis and too fast around the Sun. Indeed, a day on Venus is 244 times longer than on Earth. At the same time, the Venusian year lasts only 224.7 Earth days. That is, a year on Venus is shorter than a day!
Scientists suggest that in the early stages of evolution, the day on Venus was much shorter. However, due to some processes, the rotation of the planet slowed down, which led to the current state of things.
The probe "Venus Express" on approach to the planet discovered another mysterious phenomenon. In the photographs received from space, it is clearly seen that in the atmosphere of the planet above its South Pole there is a giant black funnel. It seems that atmospheric clouds are twisted into a giant spiral, which goes inside the planet through a huge hole. That is, Venus is a hollow sphere.
Of course, scientists do not seriously think about the existence of an entrance leading to the underworld of Venus, but the mysterious spiral vortices above the pole of the planet are still waiting for their explanation.
In addition, this strange atmospheric formation has two centers that are intricately connected to each other. But it is known that almost any atmospheric vortex is formed around a certain center in which there is no rotation.
Scientists cannot yet solve another riddle of Venus: why does its atmosphere rotate 60 times faster than the planet itself?
As, however, and the nature of a strange bright spot that appeared in 2009 on its surface. What contributed to the appearance of this giant "freckle": volcanic activity or turbulent eddies in the atmosphere is still unknown.
Or maybe the reason is completely different? For example, the appearance of a spot could be caused by the solar wind: the stream of charged particles ejected by the Sun, when interacting with the upper layers of the Venusian atmosphere, could well contribute to its appearance.
But, at least judging by the fact that the spot is especially visible in the ultraviolet, it did not appear as a result of a meteorite fall.
It should be said that spots on Venus have been observed not for the first time and not for the first decade, and yet it has not yet been possible to unambiguously explain their nature.
Our “neighbor” demonstrated another mysterious phenomenon to scientists in 2008. It was at this time that the researchers of the Universe in the atmosphere of Venus discovered a strange luminous fog, which, having existed for only a few days, disappeared just as unexpectedly as it appeared. Astronomers believe that on other planets, including on Earth, this phenomenon is most likely absent. Most likely, it is a certain feature that is characteristic only for the atmosphere of Venus.
Before that, in July 2007, several cases of bright glow were also noted in the southern hemisphere of the planet. And just a few days later, similar but brighter glows were detected in the equatorial regions of Venus.
What is the reason for this incomprehensible phenomenon, scientists do not yet know. True, today it is still known that all these phenomena appeared in the upper layers of the atmosphere in areas adjacent to the equator, and also that they do not have a clear period.
In addition, there are hypotheses in this regard. Most likely, scientists believe that a strange glow occurs in connection with high density Venusian atmosphere, which contains a lot of dissolved sulfuric acid. Especially a lot of it in the clouds, which are located at a height of 70 kilometers above the surface of Venus. Atmospheric processes occurring in these layers of the Venusian atmosphere lead to the appearance of sulfuric acid vapors, which rise even higher. It is there under the influence sun rays they start to glow.
It’s just not clear what mechanisms cause sulfur oxide and water to rise to such great heights and interact there. Astronomers suggest that unknown processes occurring on the surface of Venus may contribute to this.
So, the planet closest to us keeps secrets, the solution of which is not yet subject to man.
From book encyclopedic Dictionary(IN) author Brockhaus F. A.Venus Venus (lat. Venus) is one of the 12 deities of the Greco-Roman Olympus, Aphrodite among the Hellenes, the goddess of love and beauty, the mother of Cupid (Eros), the queen of nymphs and graces. According to Homer, Aphrodite, the daughter of Zeus and Dione, has a belt that can make any woman or goddess “beautiful,
From the book Unexplained Phenomena authorVenus Venus is one of major planets known already in antiquity; of all the celestial bodies, V. is second in brightness only to the sun and moon; sometimes it gives a faintly visible shadow, sometimes it is visible even during the day. The orbit of Venus lies inside the orbit of the earth, as a result of which the angular
From the book Big Soviet Encyclopedia(BE) author TSBA MYSTERIOUS DEATH IN A CLOSED ROOM Mrs. Lochlan Smith heard screams and struggles coming from the Laundromat on Fifth Avenue in New York and called the police. But when the police arrived, they saw that the laundry was closed. Only a small window was open, and
From the book 100 great mysteries of the XX century author Nepomniachtchi Nikolai Nikolaevich From the book Mythological Dictionary author Archer Vadim From the book Encyclopedic Dictionary of winged words and expressions author Serov Vadim Vasilievich From the book of 100 famous disasters authorVenus (Roman) - the ancient Roman goddess of gardens, later identified with Aphrodite, the Greek goddess of love, considered the mother of Aeneas, the legendary founder of the Roman state. Mother of the god of love, little Cupid. Later, V. was identified with oriental goddesses
From the book 100 great secrets of the Earth author Volkov Alexander ViktorovichVenus From ancient Roman mythology. Venus (Greek - Aphrodite) - the goddess of love and beauty. A common noun for a beautiful
From the book 100 great curiosities of history author Vedeneev Vasily Vladimirovich From the book of 100 famous mystical phenomena author Sklyarenko Valentina MarkovnaThe mysterious power of mountains Since ancient times, people settled their deities on mountain peaks. You can recall the ancient Olympus or Mount Sinai, where Moses received his "tablets of revelation." Recall the Japanese Mount Fuji, which is revered in the national religion - Shintoism
From the book Popular Astrologer author Shalashnikov IgorThe most mysterious map in the world Usually in Iceland they talk about fish, which is quite natural for an island whose economy "rests on the back of a herring." However, in last years a quarter of a million inhabitants of the "ice country" discuss the events of a thousand years ago and glorious
From the book 100 great secrets of the East [with illustrations] author Nepomniachtchi Nikolai NikolaevichLei - a mysterious "web" A mysterious "web" of imaginary straight lines, which supposedly connects the most significant prehistoric and medieval objects of Britain. The idea of the existence of lei originated more than 85 years ago. One Alfred Watkins, an amateur archaeologist,
From the book Secrets covert control men author Kriksunova Inna AbramovnaVenus Did you know that Venus was originally considered in Roman mythology as the goddess of flowering gardens, spring, fertility, growth and flowering of all the fruitful forces of nature. A little later, Venus became identified with the Greek Aphrodite. In this regard, since
From the book Encyclopedia of Classical Greco-Roman Mythology author Obnorsky V.Venus may have arisen as a result of a large-scale cosmic collision. Scientists suggest that this is far from a new hypothesis received new confirmation as a result of carefully prepared computer simulations of this event.
The hypothesis of the catastrophic origin of Venus may explain some of the oddities seen in our close neighbor.
Venus revolves around the Sun in an orbit relatively close to Earth. And the size of the neighboring planet is not much different from the Earth. Despite such proximity, Venus is a completely different planet. It has no satellites, imperceptible signs of tectonic plates, no oceans, almost no impact craters, it even rotates not like the rest of the planets of the solar system, but in the opposite direction.
Hugh Davies, of Cardiff University in Wales, has re-evaluated one of the hypothesized scenarios for the origin of Venus. He believes that he was able to "in one fell swoop" explain whole line strange anomalies of this planet.
Our solar system formed about four and a half billion years ago. At that time, serious collisions between celestial bodies were not rare in this part of the Cosmos. One such impact must have created Earth's moon, the moon, and also formed rock and debris in the asteroid belt between Mars and Jupiter and in the Kuiper belt at the outer edge of the solar system. But why did Venus survive, and not shatter into small fragments?
"Venus was formed as a result of the collision of two objects of more or less the same size," says Hugh Davies. Both collided celestial bodies and were probably one and a half times larger than Venus. Before the collision, both of these objects orbited the Sun in close orbits between Mercury and the Earth - approximately where Venus now orbits.
Planetologist Hugh Davies is not the first astronomer to speak out in favor of the catastrophic origin of Venus. He substantiated his point of view with new collision models in an article that appeared in a special edition of Earth and Planetary Science Letters. The idea to explain the emergence of Venus by a cosmic collision has the right to exist, however, answering many old questions, it raises as many new ones.
For example, why didn't a satellite appear during the disaster? “Astronomers believe that when planets collide, there will always be at least one satellite left,” says Davies. “But according to my model, a head-on collision of two approximately identical celestial bodies does not throw debris into outer space, from which a satellite of the planet could form.”
Davis' hypothesis, in his opinion, can explain the direction of rotation of Venus, the opposite relative to other planets in the solar system. This behavior of the planet is difficult to explain within the framework of the generally accepted idea of the formation of all planets in the solar system from a protoplanetary dust disk around a star. It is very difficult, if not impossible, to substantiate the emergence of an isolated island in a gas and dust interstellar cloud, in which movements occurred in the direction opposite to the cloud.
The collision of two space objects would reshape the surfaces of these planets. It is for this reason that on the surface of Venus there are very few impact craters common to the planets of the solar system from the fall of meteorites. Critics of the Davis hypothesis object that the surface of Venus could have been “smoothed out” by volcanic processes, as well as the upheavals associated with these processes and long-standing shifts of tectonic plates.
The impact hypothesis seems to explain the presence of nearly 96 percent carbon dioxide in Venus's atmosphere ( carbon dioxide). During the collision of solid celestial bodies, the rocks melted from the high temperature, and the carbon dioxide contained in them was released. A large amount of carbon dioxide in the atmosphere caused the "greenhouse effect" that exists on Venus. The oceans on both sides of the collision became "victims" of the disaster: water molecules broke up, while oxygen (02) combined with iron atoms, and light hydrogen (H) evaporated.
Some scientists in Europe and the United States believe that such a course of events is very likely. However, astrophysicist David Grinspoon of the University of Colorado at Boulder points out that it's not entirely clear how quickly Venus lost all of its water. “We know that the atmospheres of all planets lose gas over time,” Grinspoon points out. From the upper layers of the Earth's atmosphere, hydrogen also escapes into outer space.
Hydrogen from the decayed water molecules from Venus could have been released into the surrounding region of the Cosmos. "But we don't know how fast this process happened on young Venus," says David Grinspoon. To clarify this question, Hugh Davis proposes to test his hypothesis. If Venus did not arise as a result of a collision of two celestial bodies, the water on its surface did not disappear suddenly, not as a result of a catastrophe, but over a long period of time. In this case, part of the water is absorbed by solid rocks.
“If we could spectrographically analyze the Venusian rocks in situ and find traces of water there, my theory would be disproven,” says Davies. The opportunity will come soon: Russia, Japan, and the United States are planning to send robotic research spacecraft to Venus to clear up many of the disputes surrounding our enigmatic solar system neighbor's early existence.
Venus is our closest neighbor. Its dimensions, mass and density of rocks are close to those of the earth. At the same time, its magnetic field is almost three times weaker than on Earth. Venus rotates very slowly around its axis in the opposite direction to the rotation of the Earth. The pressure on its surface reaches 10 million Pa, and the temperature is about +500 ° C. At an altitude of 49 km, a powerful layer of clouds extends above the planet. This does not exhaust the mysteries of Venus. Until recently, the reasons for the sharp depletion of its atmosphere with water, the mechanism of hurricane-force winds at altitudes of about 60 km, the structure of its relief, the composition of the constituent rocks, etc., remained unclear until recently.
Now, thanks to the systematic study of the planet by Soviet scientists, many of its secrets have been revealed.
Unlike other terrestrial planets, the study of Venus with the help of telescopes proved impossible. After all, even M. V. Lomonosov, observing on June 6, 1761, the passage of the planet across the disk of the Sun, established that it was surrounded by "a noble air atmosphere, such (if only not more) than is poured around our globe." Therefore, until recently, ideas about the structure of the surface and the composition of rocks on Venus remained hypothetical. At the same time, some researchers came to fantastic constructions. It was assumed, for example, that hydrocarbons could form in the atmosphere of Venus. In this case, according to the American scientist F. Hoyle, Venus should be covered with an ocean of oil. In another version, it was assumed that complex molecules close to those plastics that are obtained in factories can be created in the atmosphere, and the surface of the planet is lined with a layer of natural plastic. According to the American researcher E. Epik, Venus is characterized by strong dust storms, the lower layers of the atmosphere are saturated with dust, which helps maintain a high temperature. In this case, the surface should also be covered with a layer of dust, just as it was envisaged by T. Gold's "dust hypothesis" for the Moon. I can't even believe that all this was seriously discussed just recently. But to be sure, it is enough to refer to the book by F. Whipple "Earth, Moon and Planets", which was published in Russian translation in 1967. Similar ideas are captured in the colorful album "Planets of the Solar System", published in Prague in 1963. This album was prepared by Czech researchers J. Sadil and L. Peshek, combining fiction with scientific ideas. Expressive, bright landscapes depict reddish rocks, an approaching dust storm, volcanic craters with lakes of boiling sulfur, gloomy sea expanses, stunted shoots of vegetation on the shores. In these landscapes, all the main points of view on the nature of the surface were displayed, which allowed conditions of a humid climate here with the development organic world, close to the Paleozoic on Earth, dry arid deserts or oceanic spaces.
In 1961, the first spacecraft was launched towards Venus. The Venera-1 station passed at a distance of less than 100,000 km from the planet. Venera-2, launched in 1965, approached the planet at a distance of 24,000 km. March 1, 1966 Venera-3 successfully reaches the surface of the planet.
The station "Venera-4" made an interplanetary journey in 1967. Its descent vehicle smoothly plunged into the atmosphere of the planet with the help of a parachute. Temperature, pressure and composition of the atmosphere were measured. In 1969, the Venera-5 and Venera-6 stations were sent to Venus. Their landers probed the atmosphere up to 20 km above the solid surface. In 1970, the descent vehicle of the Venera-7 station made a soft landing on the planet. Within 23 minutes after landing, it received signals with information about the operation of the instruments. In 1972, the descent vehicle of the Venera-8 station made a soft landing on the surface of the planet, from which important information was received for 50 minutes.
1975 was marked by outstanding achievements in the study of Venus. Two stations "Venera-9" and "Venera-10" were put into orbit artificial satellites this planet. Their descent vehicles smoothly descended to the surface. Panoramic television images of the area and other scientific information were received from both devices for 53 and 65 minutes.
In 1978, the study of Venus was continued by the Venera-11 and Venera-12 stations, which reached the surface south of the Beta region. Finally, in 1982, the Venera-13 and Venera-14 stations, having made a soft landing on the surface of the planet, made it possible to carry out a whole complex scientific research, including drilling and sampling of soil for chemical testing. As a result of the outstanding research performed by the AMS of the Venus series, hypotheses have been replaced by rigorous scientific data. There was an opportunity to lift the veil of mystery of some phenomena on the planet.
At the present time, one can definitely speak about the composition of the Venusian atmosphere. As previously assumed, it consists of carbon dioxide - 97%. In addition to it, nitrogen is present in an amount of about 3%. Fractions of percent fall on inert gases (mainly argon), oxygen, hydrogen sulfide, hydrochloric and hydrofluoric acids, water vapor and some other elements.
The huge amount of carbon dioxide in the atmosphere of Venus is associated mainly with volcanic activity. On Earth, volcanic eruptions release carbon dioxide into the atmosphere. Periodic changes in the climate on Earth, which led to glaciations, are associated by some scientists precisely with fluctuations in the content of carbon dioxide in the Earth's atmosphere. On Venus, the carbon dioxide atmosphere creates a kind of "greenhouse effect", preventing the planet's thermal radiation from passing into outer space. Perhaps this explains the high temperatures near the surface of the planet, reaching 470 ° C.
Of particular interest are the clouds of Venus, which completely hide its surface from observation from Earth. They are at an altitude of about 49 km and reach a thickness of 20 km. According to Soviet researchers L. V. Ksanfomaliti, M. Ya. Marov, and A. D. Kuzmin, who analyzed the data obtained by the Venera and Pioneer-Venus stations, the clouds have a layered structure. The upper part of the clouds, apparently, consists of droplets of sulfuric acid, and in their middle and lower parts, in all likelihood, salts predominate. of hydrochloric acid in the form of crystalline particles.
The complex dynamics of the atmosphere and the movement of clouds is noted. Apparently, there are powerful polar vortices and simply strong winds, most intense at altitudes above 40 km. Near the surface of the planet, the winds are weak. This also explains the absence of dust at the landing sites of the descent vehicles of the Venus stations.
Due to the development of a powerful atmosphere, sounding remains the only reliable means of remotely studying the surface. With the help of ground-based radio telescopes, the near-equatorial strip and individual sections with a diameter of 1500 km were studied. Experiments on radio mapping of Venus were carried out from the Venera-9 and Venera-10 stations. The signals reflected from the surface of Venus were received by terrestrial radio telescopes. At the same time, several extended ledges were established in the southern hemisphere, elongated in the latitudinal direction for several hundred kilometers at a height of up to 3 km.
The radar survey of Venus was carried out from the American Pioneer Venus satellite. The resolution of these radio images is about 30-50 km. According to satellite radar sounding data, a map was compiled covering 83% of the planet's surface, between 75 ° N. sh. and 63°S sh.
Data on the relief of Venus make it possible to distinguish lowlands on its surface, which are depressions, hilly plains and mountain ranges.
Lowlands, located below the average level of the planet (6051 km) by 1-2.5 km, occupy 16% of its surface. They form two wide arcuate bands of depressions located on both sides of the equator and touching with their convex parts almost along the zero meridian. They have a smooth relief and are weakly saturated with ring structures of impact origin, which indicates the relative youth of the relief.
Hilly plains occupy 60% of the surface. Their hypsometric level does not exceed 500 m from the average level of the planet. They are distinguished by uniform reflectivity in the radio range. The main landforms are small ridges, hills and depressions. The surface of the plains is complicated a large number ring structures-craters, the diameters of which reach 400-600 km, and the depth is 200-700 m. Some structures have central hillocks, which confirms their impact origin. The relatively shallow depth of the craters, together with traces of destruction, testifies to their antiquity. Distinctly pronounced large craters were named Lisa, Meitner, Sappho and Eva. There are numerous small craters with a diameter of 150-200 km and a depth of a few hundred meters. The presence of hilly plains on the surface a large number of heavily destroyed ancient craters gives grounds to compare them with the ancient continental regions of the Moon and Mars. There are practically no large shield volcanoes within the continental plains. An exception may be Mount Hathor, but its volcanic nature has not yet been strictly established.
Elevated areas cover 24% of the surface, forming four isolated mountain country: Land of Ishtar and Land of Aphrodite and the regions of Beta and Alpha. The land of Ishtar is a plateau, complicated by mountain structures. Its height is 3-7 km above the average level. The plateau has the shape of a wide oval, elongated in the latitudinal direction for 2000 km. It is separated from adjacent plains by steep ledges. A relatively leveled area within the land of Ishtar was called the Lakshmi Plateau. The plateau is framed by the Akna, Freya and Maxwell mountains. Registered in the Maxwell Mountains highest point planet, rising 11.8 km above the average level and 9 km above the terrain adjacent to the mountains. On the eastern slope of the Maxwell Mountains there is a crater 100 km in diameter and 1 km deep. It is assumed to be of volcanic origin.
The land of Aphrodite has the shape of a latitude-oriented oval with a length of 1500 km. Its peaks rise up to 9 km above the average level. According to radio astronomical observations, rounded uplifts have been identified within the Aphrodite Land. Their diameter is 700 km at a height above the surrounding area of 6-8 km.
The Beta region is a meridionally oriented uplift 5-6 km above the average level, topped by two large shield volcanoes - the Rhea and Tei mountains. One of the volcanoes has a relative height of 5 km and a diameter of about 700 km. At its top is a caldera with a diameter of about 90 km. This volcano is larger than the largest volcano on Mars - Olympus, but inferior to it in height. American researchers R. Saunders and M. Malin suggested that the Venusian volcanoes cannot be too high because of the greater gravity on the planet than on Mars. In addition, on Venus, the relief should be actively destroyed under the influence of chemical weathering due to the high content of acids and other active components in the atmosphere.
The Alpha region is a rise 1800 m above the average level. It is characterized by significant indentation due to the development of subparallel faults.
The tectonic nature of the elevated regions of Venus should be judged taking into account the youth and significant dissection of the relief developed within them, the absence of ancient large destroyed craters of impact origin, the confinement of all the largest shield volcanoes to them, and a clear connection with rift structures. All this gives full grounds for comparing the elevated regions of Venus with the tectonic-volcanic uplifts of Mars Tharsis and Elysium.
In the central part of the planet, a number of cracks can be traced, forming a rift system, which may have a global character. In terms of plan, the rift system, according to A. M. Nikishin, resembles a huge triangle oriented from east to west, the base of which is located south of the Beta Rise. In the latitudinal direction, the rift system of Venus extends along the Aphrodite Rise for a distance of more than 20,000 km.
Despite the development of the rift system, it can be assumed that, in general, compared with the Earth and Mars, the number of faults on Venus may be less. Due to the slow rotation of the planet and the low values of the Coriolis forces, the system of planetary fracturing is apparently not so intensively developed on it.
The main stages of tectonic evolution can be judged on the basis of the features of the surface structure of Venus, taking into account the data of comparative planetology. Initially, an ancient crust of the continental type arose, which experienced an intense meteorite bombardment. By analogy with the Moon, this process ended approximately at the turn of 4 billion years. Later, depressions formed, filled with basalts, as well as on other planetary bodies of the terrestrial group. The youngest tectonic elements are tectonic-volcanic uplifts crowned, as on Mars, by giant shield volcanoes. Let's hope that, unlike Mars, these volcanoes have not yet ceased their activity. In this case, the peculiarities of the composition of the atmosphere of Venus and the concentration of lightning near volcanoes, the freshness of detrital material, and the development of steep slopes near the Beta Rise with its clearly defined large volcanoes will be explained.
Determining the composition of the rocks of Venus became possible after landing on its surface of descent vehicles from the station of the Venera series, on which gamma spectrographs were installed. They analyzed the content of natural radioactive elements in the soil: uranium, thorium and potassium isotope. The type of rock at the landing site of the AMS Venera-8 descent vehicle turned out to be close to terrestrial granites in terms of the content of radioactive elements, and to basalts in the landing areas of Venera-9 and Venera-10. The descent vehicle of the Venera-10 station determined the density of the soil using a radioactive density meter. It turned out to be 2.7 g/cm 3 , which fully confirmed the radar data. Viewing the latest panoramas of the planet and the results of chemical analyzes of rocks, according to Soviet scientists, allow us to conclude that 70% of its surface is composed of ancient basalts, analogues of which on Earth are formed at depths of 60-80 km. Preliminary data chemical analysis rocks indicate that in the landing area of the Venera-13 station there is a rock that has undergone chemical weathering and corresponds in composition to leucite basalt. This type of deep basalt rocks with a high content of potassium and magnesium is quite rare in terrestrial conditions. And the rock studied in the landing area of the Venera-14 station and representing tholeiite basalt is quite widespread on Earth.
To study the structure of the surface, television panoramic images transmitted from descent vehicles are of particular help. Thus, the descent vehicle of the Venera-9 station transmitted an image of the surface of the northeastern outskirts of the Beta region. Its surface is covered with large acute-angled stones. The diameter of the largest of them is 50-70 cm with a height of 15-20 cm. They are in the form of plates with stepped spalls. Between the stones, the surface is covered with light fine-earth material. On individual stones, dark spots are visible, resembling weathering cells. The apparatus is located on a slope with a steepness of about 30°. The slope is covered with scree. The sharp edges of the fragments indicate that they were formed quite recently and did not undergo significant destruction.
The descent vehicle of the Venera-10 station landed southeast of the Beta region, approximately 2000 km from the landing site of the descent vehicle of the Venera-9 station. He transmitted an image of the area, which is a flat rocky desert. Large boulders are more than 3 m in diameter and are covered with dark spots corresponding to depressions such as weathering cells. Stone blocks are immersed in dark soil. The block is split by cracks. In appearance, it resembles terrestrial igneous rocks that have undergone significant changes.
The panoramas of the Beta region, obtained from the Venera-13 and Venera-14 stations, clearly depict large blocks of rocky layered rock of dark gray color with a cellular surface. The space between the blocks is covered with fine-grained brownish-black material. The absence of noticeable secondary changes in the studied breeds may indicate their young age.
The problem of soil sampling at the Venera-13 and Venera-14 stations was solved in a very interesting way. According to V. L. Barsukov, special soil sampling devices took samples of the rocks, then the soil supply mechanisms transferred them inside the sealed compartments. At the same time, the temperature of the samples taken was reset from 457 ° to 20-30 ° C, and the pressure - from 10 million Pa to 10 thousand Pa. After that, the samples were fed into the receiving chambers of X-ray fluorescence analyzers, which determined the content of the main rock-forming elements in them. chemical elements(from sodium to iron) and transmitted the resulting spectra to Earth. It is likely that the composition of the atmosphere of Venus cannot but affect the rocks on its surface. This issue was considered by Soviet scientists V. L. Barsukov and V. P. Volkov. They proceeded from the latest data on differences in the composition of updrafts and downdrafts of the subcloud troposphere. The downdrafts contain elevated concentrations of water vapor and sulfur. The composition of ascending flows includes gaseous products of the interaction of gases with rocks, as well as gases of deep origin. Calculations have shown that the interaction of descending flows of the troposphere with basalts produces pyrite, anhydrite, and amphiboles, whereas in the case of ascending flows, only pyrite and anhydrite are formed. In this case, rocks such as granites should not undergo significant transformations. However, the authors rightly note that the magnitude of this kind of chemical weathering cannot be reliably determined, so it is not clear whether Venus is covered entirely with altered rocks or only with thin surface films.
Panorama of the surface of Venus (AMS "Venera-13" and "Venera-14")
The study of Venus continues. In accordance with the program for the exploration of outer space and the planets of the solar system, in June 1983 the Soviet Union launched the AMS "Venera-15" and "Venera-16". Both stations are similar in design and purpose. The flight of two stations will make it possible to carry out independent complex measurements over various regions of Venus from the orbits of artificial satellites of this planet.
Each new result of the study of the planets brings us closer to a deeper knowledge of the Earth, and in this a significant role belongs to the achievements of Soviet science, thanks to which it was possible to reveal some of the secrets of Venus.
