Description and characteristics of the planet Venus. Planet Venus - general characteristics and interesting facts Aphelions of Venus

Among the eight planets of the solar system, Venus is perhaps the only space object that is very similar to our planet. As a result of space and astronomical studies of the planet, it turned out that its dimensions are almost the same as those of the Earth. Both planets are similar in mass and density. At first glance, it seems that Venus is the most suitable planet for life, ready to hospitably meet earthlings in the process of subsequent development and colonization. In addition, it is the brightest object in the earth's sky, for which it received the nickname "morning star". A person naively believed that a beautiful appearance corresponds to the same iridescent and attractive reality. Maybe it was so many billions of years ago.

Today, the “morning star” is blacklisted and recognized as one of the most hostile extraterrestrial worlds for humanity. Scientists, having studied the information about the planet obtained as a result of the flights of the American and Soviet automatic stations "Mariner" and "Venus", put an end to the hypotheses and theories in which Venus was given the place of an extraterrestrial cosmic paradise.

Discovery of the second planet in the solar system

The frequent appearance of Venus in the sky and its brightness have become one of the reasons for the increased interest in this space object. Even in ancient times, astronomers and stargazers paid attention to a bright star, burning with white light in the morning dawn. For an earthly observer, it has always been extremely interesting to learn more about this curious cosmic object. Subsequently, it turned out that there is simply no other planet in the solar system capable of shining so brightly like Venus. In addition, it quickly became clear that this is the closest planet to Earth, literally our neighbor in a vast and endless space.

Ancient astronomers, under the influence of the beautiful radiance of the planet, gave our neighbor a sonorous and beautiful name - Venus, in honor of the ancient Greek goddess of love. Thanks to its successful and beautiful appearance, the planet is firmly entrenched in the culture of mankind, becoming a favorite object in literature.

The first information about the planet dates back to 1500-1600 BC. Description of a bright object in the sky, the current scientists found in the ancient Babylonian texts. The ancient Egyptians, Greeks and Indians of the Mayan tribe were well acquainted with the "morning star". The discovery of Venus as a planet took place only in the 17th century. First, Galileo Galilei discovered that Venus moves around the Sun and has phases similar to those of the moon. Galileo compiled the first scientific description of an observed object and its movement across the sky. In 1639, the English astronomer Jeremy Horrocks, with his telescope, managed to discover the planet during its passage through the solar disk. The Russian scientist Mikhail Lomonosov, during his observations, managed to discover the atmosphere of this celestial body, which gave reason to consider Venus a planet that has every chance of being inhabited.

The data obtained as a result of astronomical observations were very valuable and suggested to scientists that this planet and our Earth have much in common. There was a glimmer of hope that the physical conditions on Venus are very similar to the parameters of the earth's habitat. For a long time, in the scientific community and among science fiction writers, there was an opinion that the second planet in the solar system was the cradle of extraterrestrial civilization. Only in the second half of the twentieth century did man receive accurate astrophysical data about Venus, which debunked the myth of the planet's fitness for any life forms.

Astrophysical characteristics of Venus

Venus is the third brightest object in our starry sky, second only to the Sun and Moon. The planet is located on a heliocentric, almost regular circular orbit of 108.2 million km. from our star. The closest planets to Venus in the solar system are Mercury and Earth. The distance from Venus to Earth varies over a wide range from 38 to 261 million kilometers.

The rotation of the planet around its own axis takes 243 Earth days. However, due to the fact that Venus turns in the opposite direction from the Earth, from East to West, the value of the Venusian day decreases exactly by half. A Venusian day equals 116.8 Earth days.

Moving in orbit around the Sun at a speed of 35 km / s, the planet makes a complete revolution in 224 Earth days. A characteristic phenomenon is that for Venus, the orbit and rotation around the Sun are in a strange discrepancy. Due to its extremely slow rotation around its own axis, combined with the period of rotation of the planet around the Sun, Venus faces the Earth in most cases with almost the same side. This happens mostly when it is closest to Earth.

If you make a flight to Venus aboard a spacecraft, the travel time will take 305 months. The first flight of the Mariner 2 space probe took only 153 days. The minimum distance to Earth is 90-100 days.

The composition of the planet Venus: structure and structure

Venus belongs to the group of rocky planets, the surface of which has a solid and rocky base. Unlike the gas giants Jupiter, Saturn, Uranus and Neptune, the second planet has a high density. The average density of the planet is 5.204 g/cm3. In terms of basic physical parameters, Venus is very similar to Earth. This is evidenced by the density of the planet, its mass and size.

The main parameters of Venus are as follows:

• the average radius of the planet Venus is 6052 km;
• the diameter of the planet in the equatorial plane is 12100 + - 10 km, 95% of the earth's diameter;
• the length of the equator of Venus is 38025 km and is also 97% of the length of the earth's equator;
• the surface area of ​​the "morning star" is 460 million square kilometers, 90% of the earth's surface area;
• the astronomical mass of the planet Venus is 4.87 trillion trillion kg;
• the volume of the planet is 928 billion km3.

As can be seen from the list, Venus, in terms of basic physical parameters, is the twin planet of our Earth. However, this is only a form. In terms of its content, Venus is far from the same as we are used to presenting it. The surface of the planet is hidden from the outside world by dense clouds that saturate the Venusian atmosphere.

The composition and structure of the planet are almost the same as the Earth. It also has a metallic core surrounded by a mantle. The surface of the planet, just like on Earth, is represented by a thin crust. It is generally accepted that the Venusian core with a diameter of about 6000 km has an iron-nickel composition. The thickness of the mantle is quite impressive, about 3000 km. It is not possible to establish the exact chemical composition of the Venusian mantle. Probably, as on Earth, it is based on silicates. The crust on the planet is identical in thickness to the Earth's parameters and has an average thickness of 16-30 km.

This is where the similarities between the two planets end. Then there are significant differences that make both planets perfect opposites. Tectonic processes on Venus took place in the distant past. The formation of the Venusian crust ended approximately 500-600 million years ago. The surface of the planet is represented by frozen basalt seas, separated by vast hills. Some elevations on the surface are higher than on the ground, and the height of the Venusian mountains reaches 11 km. Depressions and hollows, similar in shape and structure to the earth's oceans, occupy 1/6 of the planet's surface. There are not many craters of astrophysical origin on the planet. The largest of them has a diameter of 30 km, made by a fallen asteroid more than 1 million years ago.

What state the inner core of the planet is in is unknown. However, the almost complete absence of a magnetic field speaks in favor of the fact that the core is in a frozen state. The absence of convection between the liquid inner layers of the planet leads to the absence of the dynamo effect that results from friction between the inner layers of the planet. This explains why Venus, one of the two twin planets of the terrestrial group, got such a weak magnetic field, only 5-10% of the strength of the earth's magnetosphere. The magnetic field of Venus is very weak and is mainly formed due to particles of the solar wind captured by the planet's gravity.

Accordingly, on Venus, the magnitude of the free fall acceleration is also less - 8.87 m/s2 against 9.807 m/s2 on Earth. In other words, a person on the surface of Venus will weigh 10% lighter than on our home planet. A more detailed study of the internal structure of the planet is not possible today. The data obtained so far are the result of mathematical calculations and radar scanning of the planet's surface.

The most interesting object on Venus is the atmosphere of the planet

The first data obtained from a photo from space about the surface of Venus did not become a breakthrough in the study of the planet. The surface of Venus is hidden from view by dense layers of the atmosphere. It is she who is the decisive factor that forms the relief of the planet in the absence of active volcanic activity on the planet. Two forms of surface erosion are observed here - wind and chemical. The material ejected as a result of volcanic eruptions enters the planet's atmosphere and already there, being transformed in the course of chemical reactions, falls to the surface in the form of Venusian precipitation.

The chemical composition of the planet is quite simple:

• carbon dioxide 96.5%;
• the amount of nitrogen does not exceed 3.5%.

Other gases in the planet's atmosphere are present in microscopic quantities. However, despite the almost complete absence of oxygen and hydrogen in the atmospheric layers, the planet has an ozone layer, which is located at an altitude of 100 km.

The Venusian atmosphere is the densest among the terrestrial planets. Its density is 67 kg/m3. In other words, the lower atmosphere is a semi-liquid medium dominated by carbon dioxide. As a result of this high saturation of the troposphere, the atmospheric pressure near the surface of Venus is colossal, amounting to 93 bar. This roughly corresponds to the earth's pressure, which will be at a depth of 900 meters in the world's oceans. The high concentration of carbon dioxide in the planet's atmosphere has caused the greenhouse effect. As a result, a high temperature is noted on the surface of the planet, which can reach 475 degrees Celsius. This is more than on Mercury, which is much closer to the Sun.

There is no need to talk about the presence of water on Venus under such atmospheric conditions. Dense clouds, composed of sulfuric acid, rain down on the surface of the planet with acid rain, and the Venusian seas are lakes of sulfuric acid.

Winds on the surface of Venus are raging serious. The entire atmosphere of the planet is one huge raging hurricane rushing around the surface of the planet at a speed of 140 m/s. Accordingly, it is not difficult to imagine how strong the wind blows on the planet.

The atmosphere of Venus is the main difference from our planet. The existence of any life forms in such conditions, where the temperature reaches the melting point of lead, is impossible. In addition, the high concentration of CO2 leads to the fact that instead of water on the planet, the main liquid is sulfuric acid.

Future Plans to Explore Venus

Venus is the closest space neighbor to us, a bright and beautiful star in our firmament, in fact, is a real universal hell. The space exploration that man undertook in relation to Venus in the second half of the 20th century made it clear that Venus is a hostile environment for us. Within 40 years, 30 spacecraft were launched to the "morning star".

Basically, the research was carried out within the framework of the Soviet program for studying the planet "Venus" and the American space program "Mariner". The last spacecraft that completed the cycle of space exploration of the "morning star" were the European probe "Venus Express" and the Japanese apparatus "Akatsuki", launched to Venus in 2005 and 2010, respectively.

If you have any questions - leave them in the comments below the article. We or our visitors will be happy to answer them.

Mankind has always been interested in a bright star, giving its bright light in the morning hours or observed in the early twilight. This brilliant celestial body - Venus - the second planet of the solar system. However, despite such an attractive appearance, in reality, the alluring and distant world is a hellish boiling cauldron in which there is no place for anything living.

Discovery of the planet Venus

The celestial body, which appears in the sky, has a brightness of -4.6 apparent magnitude, has long been known to man. In terms of its brightness, Venus is the third object in the sky, second only to the Sun and the Moon. The most convenient time for observing this beauty is the morning and evening hours. Periods of morning and evening visibility alternate over 585 days.

For this, she was nicknamed “the morning star”. As a rule, Venus is easy to see with the naked eye in the western or eastern part of the sky, not far from the horizon line. The planet appears quite often, delighting amateur astronomers with its brilliance. The sight looks impressive when the morning star appeared in the company of Jupiter. Two bright points in the night sky will not leave anyone indifferent.

For the first time, the second planet from the Sun was observed by the ancient Chinese and Persians. In those distant years, Venus served as a natural indicator of time. The time of the appearance of the morning star determined the approximate time of day. Ancient astronomers and astrologers considered Venus to be a planet. Due to its astrophysical parameters, the celestial body fit perfectly into the heliocentric system proposed by Aristarchus of Samos. Much later, in the 16th century. Through the efforts of Copernicus, Venus firmly took an honorable second place in the heliocentric system.

Despite the fact that mankind received information about Venus in ancient times, the honor to discover the celestial body fell to Galileo Galilei. It was he who first saw the morning star in his telescope in 1610. The scientist managed to detect Venusian phases similar to those of the moon, which confirmed the theory of the heliocentric system of motion of celestial bodies. After 29 years, in 1639, scientists were able to observe Venus in all its glory. The planet made its way, passing through the huge solar disk.

In the future, a close study of the second planet from the Sun gave every reason to consider Venus the twin of our Blue Planet. Through the efforts of Mikhail Lomonosov, the "morning star" acquired an atmosphere. For a long time, information about the size of a celestial body and astrophysical data gave reason to consider the planet suitable for the existence of life. However, the morning beauty stubbornly concealed her true appearance. Observations of the planet with the help of powerful and perfect optics did not shed light on the natural nature of Venus. Only the flights of the first automatic probes in the second half of the twentieth century lifted the veil of secrecy.

Common knowledge about the planet Venus

To date, the physical and astrophysical parameters of the planet closest to the Earth are well known. This object is a massive solid body orbiting our star in an almost circular orbit. The maximum removal of the "morning star" from the Sun is 108,942,109 km. At perihelion, Venus approaches the center of the solar system at a distance of 107,476,259 km. Despite the almost ideal parameters of the Venusian orbit, the distance between the morning beauty and the Earth varies over a wide range - from 36 to 261 million km. With such an arrangement of two neighboring planets, it will take a little more than 6 months to overcome the distance between Venus and the Earth. Launched on November 9, 2005, the Venera Express spacecraft reached our neighbor after 153 days.

The record for the time - 97 days spent on a flight to Venus, belongs to the Soviet automatic interplanetary station Venera-1. For two weeks longer, 110 days, the American probe "Mariner-2" flew to the "morning star". The ship, launched on August 8, 1962, reached the vicinity of another planet on December 14 of the same year. Thanks to the flight of "Mariner-2", the first photos of the object from space were obtained.

With the help of space probes, earthlings were able to see Venus, a planet very similar to our Earth, in all its glory. The size of the "morning star" is almost identical to the size of the Earth. The average radius of the planetary disk is 6051 km, which is 320 km less than the radius of the planet Earth (6371 km.). The surface area of ​​the Earth's neighbor in space is 460 million km².

Venus has a solid surface and belongs to the terrestrial planets, which, along with our planet, includes Mercury and distant Mars. For comparison, just look at the data on the mass and average density of Venus in comparison with other terrestrial planets:

• Mercury has a mass of 3.33022 10²³ kg and an average density of 5.427 g/cm³;
• the mass of Venus is 4.8675 10²⁴ kg, and the average density is 5.24 g / cm³;
• the mass of the Earth is 5.9726 10²⁴ kg at an average density of 5.5153 g/cm³;
• Mars weighs 6.4171 10²³ kg with an average density of 3.933 g/cm³.

From the above data it is clearly seen how similar the second and third planets of the solar system are Venus and the Earth. This is once again confirmed by the Venusian gravitational force, equal to 8.87 m / s². On Earth, this parameter is 9.780327 m/s².

As for the astrophysical parameters, this is where the differences begin. The nearest neighbor of the Earth makes a complete revolution around the Sun in 224 Earth days. The rotation of the planet around its own axis is generally carried out in the opposite direction, i.e. The sun on Venus rises in the West and sets in the East. Despite the rather frisky run in orbit - the planet's speed is 35 km / s - the "morning star" is the slowest one to rotate around its own axis. A Venusian day is 242 Earth days.

Description of the planet Venus, interesting facts

The geophysical characteristics of the second planet in the solar system are quite curious. With an outward resemblance to the Earth, the "morning star" has a similar structure and structure.

Venus is the closest planet to us in structure. The similarity of the two celestial bodies is explained by the high density, which is characteristic of all planets of the terrestrial group. Scientists suggest that the "morning star" has a heavy iron-nickel core. However, despite the high temperatures, the core of the planet does not have convection, which does not provide the celestial body with a strong magnetic field. The core diameter is believed to be 3,000 km.

The mantle of the heavenly beauty occupies a fairly large volume. The thickness of this layer is equal to half the radius of the planet - 3000 kilometers. High temperatures prevail here, providing constant eruptions to the surface of lava flows. The Venusian crust has an average thickness of 30-50 km and consists of silicate and siliceous rocks. A significant difference in the structure of the surface layer of the second planet of the solar system is the absence of tectonics. On Venus, tectonic activity ceased billions of years ago, while on Earth, such processes occur constantly. The celestial body turned into a hot stone ball rushing in orbit. Due to the absence of tectonic processes, the “morning star” does not have a generated magnetic field.

If we can only guess about the deep structure of the earth's neighbor, the data on the surface of the planet are quite eloquent. This is the hottest place in the solar system. It turned out that the temperature on the surface of the heavenly beauty is very high and reaches 475⁰ Celsius. Under such conditions, there is no water on the planet. It is absent in both liquid and vapor states. It is very dry and hot here - a real hell.

As for the Venusian landscape, here one can see a typical picture of primeval chaos. Two-thirds of the planet's surface is covered with flat and smooth plains, formed by constant large-scale lava eruptions. The vast plains on the "morning star" are comparable in area to the earth's continents. In the process of research, the Venusian continents were named after the goddesses of love, taken from the myths of different countries. The largest Venusian volcano Maat has a height of more than 8 thousand meters. This is higher than any terrestrial volcano. The Venusian plains are indented by lava rivers, which in some places reach a length of 3-3.5 thousand kilometers.

The geological past of the planet is represented by mountainous regions, among which the Maxwell Range stands out in particular. The maximum height of the mountain peaks is 11,000 meters.

The composition of the atmosphere of our space neighbor

A distinctive feature of the planet's surface was a small number of craters of cosmic origin. The reliable protection of this distant world is the atmosphere of the planet. The main component of the Venusian air envelope is carbon dioxide. Small amounts of nitrogen, water vapor, sulfuric acid and molecular oxygen are present in the atmosphere. The lowest layer, 65 km thick, is the densest. In fact, this is a sulfuric acid fog that has spread over the entire surface of the “morning beauty”. This is confirmed by the enormous pressure that is present on the surface of the planet, more than 93 bar. Atmospheric pressure decreases with altitude and becomes similar to Earth's parameters.

The high concentration of carbon dioxide in the planet's atmosphere is due to the high volcanic activity that was observed on the planet in the past. Carbon dioxide and today in large quantities continues to enter the atmosphere of Venus. This process is facilitated by intense lava eruptions, which do not stop today. High concentrations of CO₂, water vapor and sulfur dioxide in the surface layer of the planet generate the strongest greenhouse effect. Solar energy is trapped by the dense atmosphere, which leads to significant overheating of the planet's surface. In view of this, the daily temperature difference on Venus is negligible. The temperature gradually decreases with height, and the density of Venusian sulfuric acid clouds also decreases with height.

Morning Star Research

The first accurate data were obtained thanks to the flight of the Soviet spacecraft Venera-7, which landed on December 15, 1970 on the surface of the second planet in the solar system. Subsequently, the Soviet space program "Venus" was continued. The Venera-9 and Venera-10 spacecraft provided the scientific community with images of the Venusian landscape. A distinctive feature of the planet's surface was a small number of craters of cosmic origin. The reliable protection of this distant world is the atmosphere of the planet.

Following the Soviet AMS "Venus", the American probes "Piner-1" and "Pioner-2" set off for the "morning star", which were engaged in mapping the surface of Venus. Then came the turn of the Soviet apparatus "Vega", launched in 1984.

Scientists received the most complete information about our neighbor from the Magellan station, which worked in orbit of the morning goddess for almost five years. Thanks to this spacecraft, we now have an accurate map of the Venusian surface. The most recent acquaintance with the second planet of the solar system can be called the flight of the ESA Venus Express spacecraft, which went on a date on November 9, 2005.

On the distant star Venus
The sun is fiery and golden,
On Venus, ah, on Venus
Trees have blue leaves.

Nikolai Gumilyov

The planet of the Roman goddess of love and beauty, the morning and evening star... You must have seen her - early in the morning, when the sun is about to rise, she is the last one to disappear in the brightening sky. Or, on the contrary, it lights up first against the background of a fading sunset - the brightest, except for the Sun and the Moon, is 17 times brighter than the brightest star - Sirius. If you look closely, it does not look like a star - it does not twinkle, but shines with an even white light.

But at midnight you will never see her. Venus for an earthly observer does not move away from the Sun by more than 48 °, because we are looking at its orbit "outside". Therefore, Venus is clearly visible in two cases: when it is to the right, west of the Sun - this is called western elongation - at this time, it sets before the Sun and rises before the Sun, so it is clearly visible before sunrise; and when it is to the left of the Sun and follows it across the sky during the day, then it is visible in the evening (Fig. 1). The period when the planet is close to the Earth-Sun line is called connection(the planet "connects" with the Sun), at this time it is not visible.

However, not quite so. Venus is not visible to the eye when it is close to the Sun, but with a telescope - if you know exactly where to look for it - you can see it. (By the way, the task is to draw what Venus looks like in a telescope, for example, in eastern elongation.) And occasionally it happens that for an earthly observer it passes not near the Sun, but directly across its disk. During such a passage, observing it through a telescope, Lomonosov discovered the atmosphere of Venus. When would O Most of Venus was already on the disk of the Sun, for a moment he saw a thin luminous rim around the rest of the planet (Fig. 2). Many have seen this rim, but did not attach any importance to it. And only Lomonosov realized that it was the slanting rays of the sun that illuminated the atmosphere of the planet, like a flashlight in the dark illuminates the smoke and makes it visible.

This atmosphere was not at all a gift. For starters, it turned out that it is opaque to "ordinary" (visible) light and does not make it possible to see the surface of the planet: it's like trying to see the bottom of a saucepan through a layer of milk. But the main thing people learned only when they tried to land a descent vehicle on Venus.

Venus is almost the size of the Earth, and not much less in mass; it would seem that these two planets are almost the same. So even at the beginning of the 20th century, it could be assumed that trees grow on Venus and, in general, someone lives. Or that, for example, earthlings can settle on it. However, these hopes did not come true: the first device that tried to land on Venus (in 1967) was crushed before reaching the surface!

It turned out that on Venus there is a monstrous atmospheric pressure: almost 100 times more than on Earth. For every square centimeter of the surface, a column of air presses with such force, as if on Earth a hundred-kilogram weight was placed on this centimeter! The density of the Venusian "air" is only 14 times less than the density of water. The temperature is always - both during the day and at night - 470 ° C, more than in the hottest place on Mercury! In addition, the atmosphere, which consists mainly of carbon dioxide (CO 2), contains a bunch of poisonous and caustic sulfur compounds, including sulfuric acid. So far, not a single descent vehicle - and there were about a dozen of them - has lasted in this environment for more than two hours ...

Try to imagine this picture. The sky on Venus is orange, always covered in clouds of sulfuric acid. The sun is never visible behind a continuous layer of clouds. Naturally, there is no water - at such a temperature it has long evaporated (and it looks like there were oceans before!). Sometimes there are acid rains (literally: acid instead of water), but they do not reach the surface - they evaporate from the heat. There is almost no wind below, only 1 m / s, but the “air” is so dense that even such a weak wind raises dust and small pebbles, all this seems to be floating in the air. But above, at the height of the clouds, a giant hurricane is constantly raging - the wind speed there reaches 100 m / s, that is, 360 km / h, and even more! (Where this hurricane came from is still unknown.)

How did it happen? Why is this picture so different from Earth? Let's figure it out.

Sulfur compounds and carbon dioxide (of which 96% on Venus) entered the atmosphere from volcanoes. There are many volcanoes - thousands, the entire surface is covered with solidified lava. It is possible that some of the volcanoes are still active, but so far no eruptions have been seen on Venus.

All these "volcanic" gases have heavy molecules: for example, a carbon dioxide molecule weighs 1.5 times more than the nitrogen and oxygen molecules that make up the earth's atmosphere. And there are a lot of them. Therefore, the "air" there is so dense and heavy.

Why is the temperature so high? Again, volcanic gases, primarily carbon dioxide, are to blame. He creates the so-called Greenhouse effect, the essence of which is this. The sun illuminates the planet (Earth, for example) and thereby heats it up, transferring to it every second (through the rays of light) some energy. Thanks to this energy, winds blow, rivers flow, plants and animals live. But energy never disappears, it can only change from one form to another. We ate a sandwich - the (chemical) energy hidden in it was spent on heating our body. A river flows - the water hits the stones and also heats them. So in the end, the energy transferred by the Sun to the planet turns into heat - the planet heats up. Where does the energy go next? The heated surface of the planet emits a slightly different radiation, invisible to the eye - infrared. The hotter the surface, the stronger the radiation. This radiation goes into space and carries away "extra" energy - exactly as much as it comes from the Sun. A balance is maintained: how much you take - so much return.

And if you return (that is, radiate) less than you took (received from the Sun)? Energy will begin to accumulate on the planet, and the temperature of the surface and air will rise. A more heated surface emits more infrared rays - and soon the balance will be restored, but at a higher temperature.

Here is the greenhouse effect - this is overheating, which occurs just from such a temporary imbalance. This is because carbon dioxide absorbs infrared rays. The surface of the planet emits them, but carbon dioxide in the atmosphere does not release them out into space! Solar energy with visible light gets inside, but the atmosphere does not let it go outside. This is how energy accumulates until the entire atmosphere warms up so much that its upper layer can finally radiate the required amount of energy into space and restore balance. This is what happened on Venus - in order to restore balance, its surface had to warm up by 400 degrees. This can happen to the Earth if too much carbon dioxide and other "complex" gases accumulate in its atmosphere!

There is another interesting feature. Almost everything in the solar system - all the planets and b O Most of the asteroids revolve around the Sun in the same direction. And around the axis, all the large planets rotate in the same direction - all but one. Venus rotates "not like everyone else", however, very slowly: 1 rotation around its axis in 243 Earth days, while the Venusian year lasts 225 Earth days. That is, Venus revolves around the Sun even a little faster than around the axis! Having trained on Mercury, of course, you can easily figure out how long the day would be and how long the night would be on Venus if these two periods coincided (this answer is almost real, since the difference is small). The resonance with the Sun is again incomplete - and again, perhaps, the reason is in the Earth: just as Mercury in its “waltz” always turns to us with the same side when it meets, so Venus in each conjunction with the Sun is turned to the Earth in the same way. So inaccurate resonance with the Sun - but there is a resonance with the Earth.

Why is she spinning the wrong way? Unclear. There are different hypotheses, one more doubtful than the other. All of them somehow come down to the fact that "in childhood" some kind of misfortune happened to Venus. Someone pushed or hit... On the other hand, the answer to the previous question is well known - why do all the other planets spin so unanimously (and all, except Mercury, quickly) in the same direction? Try to guess.

Answers

1. When looking through a telescope, Venus has a clearly visible disk, so the phases are also visible - like those of the Moon. And for the same reason: only its illuminated side is visible. In the eastern elongation, we see exactly half a circle “in the form of the letter P” (see Fig. 1 of the article), like the Moon in the first quarter. But unlike the Moon, the month of Venus does not grow at this time, but decreases: further on, the Earth and the Sun will be on opposite sides of it, and its crescent will become very narrow.

2. If the year and sidereal day coincided, day and night would last for a quarter of a year - see the figure below. In fact, a solar day on Venus lasts 116 Earth days, that is, more than half a year, but less than half a sidereal day.

3. Rotation (both annual and daily) in one direction is a consequence of a common origin. All the planets were “blinded” from lumps (planetesimals) in a large protoplanetary cloud, which, as a whole, slowly rotated in one (random) direction, like soup in a saucepan, if it is slightly stirred with a spoon. When the Sun was formed, the whole cloud condensed (shrank towards the center) and, like a figure skater who pressed his hands to his body in the “screw”, began to rotate faster; in physics this is called conservation of angular momentum. Separate lumps were also compressed (and very strongly), forming planets, and their rotation around the axis was greatly accelerated. Therefore, the planets rotate around the axis quickly; Mercury slowed down after that.

Artist Maria Useinova

On Earth, such pressure can also be found - in the ocean, at a depth of 1 km.

In fact, there is a small greenhouse effect (but not due to carbon dioxide, but due to water vapor) on Earth, and very handy: without it, the temperature would be 20-30 degrees lower than now.

Formally, Uranus is also spinning “in the wrong direction”, but we will talk about it separately.

You just need to draw a picture ... If it doesn't work out, see the answers.

The second in the solar system, the brightest planet in the sky after the Sun and the Moon, Venus is a muse for numerous poets and romantics. And also one of the favorite objects for observation among space explorers.

The surface of Venus is difficult to study due to thick acid clouds in its atmosphere. Such an opportunity appeared only after the invention of spacecraft and the most powerful radio telescopes, which were able to show what Venus looks like and collect the most accurate, interesting information about this amazing object.

Discovery history

The brightness of Venus made it one of the most studied celestial bodies by ancient astronomers. Sumerian astronomical tables and Mayan calendars have come down to us, which describe the full cycle of its movement.

The ancient Romans identified the star with the goddess of love (among the Greeks - Aphrodite) for its bright, beautiful white glow in the morning and evening sky. At the same time, for a long time it was believed that the Morning and Evening stars are different celestial bodies. Only Pythagoras was able to prove the opposite, so it is believed that it was he who discovered the planet Venus.

The history of the discovery of Venus was not without Galileo Galilei. He was the first to observe it through a telescope and established the order of the change of Venusian phases. The atmosphere on the planet was discovered in 1761 by Mikhail Lomonosov, but it was impossible to study its surface for a long time.

Intensive research on Venus began with the advent of radio telescopes and space probes. 28 Soviet and American vehicles were successfully sent in this direction to study its atmosphere and surface. They transmitted panoramic images to astronomers, but none of the probes that managed to reach the Venusian surface could survive in its harsh conditions for more than 2 hours. The latest spacecraft launched to Venus are the Venera Express of the European Space Agency, as well as the Akatsuki of the Japan Aerospace Exploration Agency.

In the near future, Roskosmos plans to launch an interplanetary station with an orbiting satellite and descent modules, which will make it possible to study the Venusian atmosphere. In addition to the station to study the surface, a probe will be sent in this direction, capable of operating in its harsh conditions for about 4 weeks.

Features, orbit and radius

The orbital path has a low eccentricity and is the most circular among the planetary objects of the solar system. The average radius of the orbit of Venus is 109 million kilometers. It completes a full revolution along the orbital path in 224.6 Earth days, moving at an average speed of 34.9 km / s.

A feature of Venus is that it rotates in the opposite direction for most bodies - from east to west. The most likely reason for this phenomenon is a collision with a large asteroid that changed the direction of its movement.

The Venusian day is the longest in the whole - 243 Earth days. It turns out that the year here lasts less than one full day.

Physico-chemical characteristics

In terms of its physical parameters, the second planet is close to the Earth. Its radius is 6052 km, which is 85% of the earth's. Mass - 4.9 * 10 24, and the average density value - 5.25 g / cu. see The high density and chemical composition of Venus classify it as an Earth-like object. Unlike gas giants, they are solid and composed of heavy elements.

What is Venus made of? Its surface is solidified lava rocks, rich in chemical composition of silicates, aluminum and iron. The crust goes only 50 km deep, continuing into a massive silicate mantle several thousand kilometers thick. The heart of Venus is an iron-nickel core, occupying a quarter of its diameter.

The Venusian landscape has long remained a mystery, which could only be solved by orbiting satellites that sent reliable images of the Venusian relief to Earth. Plains, which are giant layers of hardened lava from basalt rocks, occupy most of the planet's surface. Next to them are ancient, but still active volcanoes, arachnoids and deep craters.

Temperature on Venus

The second planet from the Sun is the hottest planet in our system. The average temperature at the surface of Venus is approaching 470 degrees Celsius. At the same time, during the day, temperature fluctuations are extremely small.

Why is the temperature on Venus so high? The heating of the Venusian surface is explained not so much by the proximity of the Sun, but by a dense atmosphere, consisting mainly of carbon dioxide and sulfuric acid. Under such conditions, a greenhouse effect occurs - carbon dioxide absorbs infrared radiation reflected from the ground, preventing it from passing back into outer space. At the same time, the lower layers of the atmosphere are heated to an extremely high value.

The minimum temperature on Venus can be registered in the thermosphere zone, which is more than 120 km away from it. At night, the temperature here drops to -170°C, and during the day it reaches a maximum of 120°C. The harsh climate is also determined by the winds. There is practically no wind in the lower layers, but at the level of the troposphere, the atmosphere turns into a giant hurricane with a wind speed of more than 359 km / h. Thunderstorms and lightning are constantly raging here, as well as acid rain. But it evaporates before reaching the surface, and turns into concentrated acid fumes.

Atmosphere

The closest part of the Venusian atmosphere to the surface - the troposphere - is an ocean of carbon dioxide in the state of a supercrystalline liquid. Its high density creates a hotbed near the surface, heating Venus more than any other body in the solar system.

At a level of 50-65 km above the surface in the layers of the tropopause, the temperature and pressure of the atmosphere approach the earth's values. The minimum indicators of temperature and pressure are recorded within 200 km above the surface.

The main components of the Venusian atmosphere are semi-liquid CO 2 (over 96%) and nitrogen (3.5%). The rest is inert gases, sulfur dioxide and water vapor. An extremely thin layer of ozone is located at a level of 100 km from the surface of the planet.

• It is the closest planetary neighbor of the Earth. The distance between the bodies does not exceed 42 million kilometers.
• Venus is the brightest celestial body after the Moon and the Sun, observed from the Earth. You can see it even during the day, but it is best to watch it against the background of morning and evening twilight.
• The crust of the planet is quite young - it is only about 500 million years old. This is confirmed by the extremely small number of impact craters.
• Most fragments of the Venusian relief bear the names and surnames of women. The only "male" detail of the relief is the highest mountain range, which got its name in honor of the British physicist and space explorer James Maxwell.
• Deep Venusian craters got their names in honor of the names of famous women (Akhmatova, Barto, Mukhina, Golubkina, etc.), and small ones - in honor of female names. The heights of the relief are named after goddesses from different mythologies, and the canyons, furrows and lines are named after the tin of warlike women and characters from fairy tales and myths.
• For a long time it was believed that the Venusian climate is similar to the terrestrial tropics, and life on the planet is a kind of Mesozoic on Earth. But a detailed study of its atmosphere showed that the origin of life in such harsh conditions is impossible.
• The planet has no magnetic field. Its magnetosphere is induced.
• Venus and are the only planetary bodies in our system that do not have natural satellites. But some current theories suggest that it may have previously had its own moon, which collapsed before the appearance of astronomical observations on Earth. According to another theory, Mercury was once a natural satellite of Venus.
• The planet has a high reflectivity (albedo), so on a moonless night it casts a shadow on the Earth.

The planet Venus is our closest neighbor. Venus comes closer to the Earth than any other planet, at a distance of 40 million km or closer. The distance from the Sun to Venus is 108,000,000 km, or 0.723 AU.

The dimensions of Venus and the mass are close to those of the earth: the diameter of the planet is only 5% less than the diameter of the Earth, the mass is 0.815 of the mass of the Earth, and the force of gravity is 0.91 of the earth. In this case, Venus rotates very slowly around its axis in the direction opposite to the rotation of the Earth (ie, from east to west).

Despite the fact that in the XVII-XVIII centuries. various astronomers have repeatedly reported the discovery of the natural satellites of Venus. It is currently known that there are none on the planet.

Atmosphere of Venus

Unlike other terrestrial planets, the study of Venus with telescopes turned out to be impossible, since even M. V. Lomonosov (1711 - 1765), on June 6, 1761, observing the passage of the planet against the background of the Sun, he established that Venus is surrounded by "a noble air atmosphere, such (if only not more) than is poured around our globe of the earth."

The atmosphere of the planet extends to a height 5500 km, and its density in 35 times greater than the density of the earth. Atmospheric pressure in 100 times higher than on Earth, and reaches 10 million Pa. The structure of the planet's atmosphere is shown in Fig. 1.

The last time the passage of Venus against the background of the solar disk in Russia, astronomers, scientists and amateurs, were able to observe June 8, 2004. And on June 6, 2012 (that is, with an 8-year interval), this amazing phenomenon can be observed again. The next passage will take place only after 100 years.

Rice. 1. The structure of the atmosphere of Venus

In 1967, the Soviet interplanetary probe "Venera-4" for the first time transmitted information about the atmosphere of the planet, which consists of 96% carbon dioxide (Fig. 2).

Rice. 2. The composition of the atmosphere of Venus

Due to the high concentration of carbon dioxide, which, like a film, retains heat near the surface, a typical greenhouse effect is observed on the planet (Fig. 3). Thanks to the greenhouse effect near the surface of Venus, any existence of liquid water is excluded. The air temperature on Venus is approximately +500 °C. Under such conditions, organic life is excluded.

Rice. 3. Greenhouse effect on Venus

On October 22, 1975, the Soviet probe "Venera-9" landed on Venus and for the first time transmitted to Earth a television report from this planet.

General characteristics of the planet Venus

Thanks to Soviet and American interplanetary stations, it is now known that Venus is a planet with a complex relief.

Mountainous terrain with a height difference of 2-3 km, a volcano with a base diameter of 300-400 km, and
hundredth about 1 km, a huge hollow (1500 km long from north to south and 1000 km from west to east) and relatively flat areas. In the equatorial region of the planet there are more than 10 ring structures, similar to the craters of Mercury, with a diameter of 35 to 150 km, but strongly smoothed and flat. In addition, there is a fault in the planet's crust 1500 km long, 150 km wide and about 2 km deep.

In 1981, the Venera-13 and Venera-14 stations examined soil samples from the planet and transmitted the first color photographs of Venus to earth. Because of this, we know that the surface rocks of the planet are close in composition to terrestrial sedimentary rocks, and the sky above the horizon of Venus is orange-yellow-green.

At present, human flights to Venus are unlikely, but at an altitude of 50 km from the planet, the temperature and pressure are close to conditions on Earth, so it is possible to create interplanetary stations here to study Venus and to recharge spacecraft.