Eating right: what to eat, when to eat, how to eat. Ten basic principles of nutrition. How to count calories. Food pyramid. Vitamins and microelements. Which drinks to drink and which ones not to drink. All diets are postponed. Proper diet. Ten principles

Is there life on other planets? This question has been troubling humanity for thousands of years. And scientists are trying to find at least some signs that there is life on other planets. Huge sound-collecting devices are aimed into space, recording every signal,

Is there life in boiling water? Until recently, it was believed that boiling water kills everything, even the most persistent bacteria, but nature, as always, has refuted this belief. At the bottom Pacific Ocean super-hot springs with water temperatures from 250 to 400 °C were discovered,

Is there life in the Dead Sea? The Dead Sea is a truly strange and, moreover, not the only name given by man This is one of the most unusual bodies of water on Earth. For the first time this sea began to be called “dead” by the ancient Greeks. The inhabitants of ancient Judea called

Is there life on Mars? Many people believe that there is life on Mars. But they don't distinguish fiction from real facts. Science fiction writers have written a thousand times - there is, there is, there is. The only question is who we will meet there - Aelita or someone else. Even now, when American

Are we alone in this Universe? Until now, this issue remains unresolved. But UFO sightings and mysterious space images make us believe in the existence of aliens. Let's figure out where else, besides our planet, the existence of life is possible.

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The Orion Nebula is one of the brightest nebulae in the sky that is visible to the naked eye. This nebula is located one and a half thousand light years from us. Scientists have discovered many particles in the nebula that could form life as we understand it. The nebula contains substances such as methanol, water, carbon monoxide and hydrogen cyanide.

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There are billions of exoplanets in the universe. And some of them contain huge amounts of organic matter. Planets also revolve around their stars, just like our Earth around the Sun. And if you're lucky, some of them rotate at such an optimal distance from their star that they receive enough heat so that the water present on the planet is in liquid form, and not in solid or gaseous form.

Kepler 62e is the exoplanet that most widely satisfies the conditions for supporting life. It orbits the star Kepler-62 (in the constellation Lyra) and is 1200 light years away from us. It is believed that the planet is one and a half times heavier than the Earth, and its surface is completely covered with a 100-kilometer layer of water. In addition, the average surface temperature of the planet, according to calculations, is slightly higher than the Earth’s and is 17 ° C, and ice caps at the poles may be completely absent. Scientists say there is a 70-80% probability that some form of life may exist on this planet.

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Enceladus is one of the moons of Saturn. It was discovered back in the 18th century, but interest in it increased a little later, after spacecraft Voyager 2 discovered that the surface of the satellite has a complex structure. It is completely covered with ice, has ridges, areas with many craters, as well as very young areas filled with water and frozen. This makes Enceladus one of three geologically active objects in the outer Solar System.

The Cassini interplanetary probe studied the surface of Enceladus in 2005 and made many interesting discoveries. Cassini discovered carbon, hydrogen and oxygen on the surface of the satellite, and these are key components for the formation of life. Methane and organic matter were also found in some areas of Enceladus. In addition, the probe revealed the presence of liquid water under the surface of the satellite.

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Titanium

Titan is Saturn's largest moon. Its diameter is 5150 km, which is 50% larger than the diameter of our Moon. In size, Titan surpasses even the planet Mercury, being slightly inferior to it in mass.

Titan is considered the only planetary satellite in the Solar System that has its own dense atmosphere, consisting mainly of nitrogen. The temperature on the surface of the satellite is minus 170-180°C. And although this is considered too cold an environment for life to arise, a large number of organic matter on Titan may indicate otherwise. The role of water in building life here can be played by liquid methane and ethane, which are found here in several states of aggregation. Titan's surface consists of methane-ethane rivers and lakes, water ice and sedimentary organic matter.

It is also possible that there are more comfortable living conditions beneath the surface of Titan. Perhaps there are warm ones there thermal springs, rich in life. Therefore, this satellite is the subject of future research.

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Callisto is the second largest natural satellite of Jupiter. Its diameter is 4820 km, which is 99% of the diameter of the planet Mercury.

This satellite is one of the most distant from Jupiter. This means that the planet’s deadly radiation affects it to a lesser extent. The satellite always faces one side towards Jupiter. All this makes it one of the most likely candidates for creating a habitable base there in the future for studying the Jupiter system.

And although Callisto does not have a dense atmosphere, its geological activity is zero, it is one of the candidates for the discovery of living forms of organisms. This is because amino acids and other organic matter, which are necessary for the emergence of life, were found on the satellite. In addition, there may be an underground ocean beneath the planet's surface that is rich in minerals and other organic compounds.

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Europa is one of the satellites of Jupiter. It has a diameter of 3120 km, which is slightly smaller than the Moon. The surface of the satellite consists of ice, under which there is a liquid ocean. Below the ocean, the surface is made of silicate rocks, and at the center of the satellite there is an iron core. Europe has a thin oxygen atmosphere. The ice surface is quite smooth, indicating geological activity.

You may ask, where could a liquid ocean come from at such a distance from the Sun? This is all due to the tidal interactions of Jupiter. The planet has a huge mass, its gravity greatly affects the surfaces of the satellites. Just as the Moon influences the tides on Earth, Jupiter does the same with its moons, only to a much greater extent.

The surface of Europa is greatly deformed by Jupiter's gravity; friction is formed inside the satellite, which heats up the interior, making this process somewhat similar to the Earth's movements of lithospheric plates.

Thus, we see that Europa has oxygen, a weak atmosphere, liquid water, as well as many different minerals, which are the building blocks of life.

The European Space Agency is planning a landing mission to Europe, scheduled for 2022. She can reveal many secrets of this moon of Jupiter.

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Mars

Mars is by far the most accessible planet for finding evidence of extraterrestrial life. The position of the planet in the Solar System, its size and composition indicate the possibility of the existence of life on it. And, if Mars is now lifeless, then perhaps it had life earlier.

There are many facts about the existence of life on Mars:

Most Martian asteroids found on Earth contain micro-fossils of life. The only question is whether these fossils could have ended up on asteroids after landing.

The presence of dry river beds, volcanoes, ice caps and various minerals indicates the possibility of life on the planet.

Short-term increases in the amount of methane in the Martian atmosphere have been documented. In the absence of geological activity on the planet, such emissions can only be caused by the presence of microorganisms on the planet.

Research has shown that in the past Mars had much more comfortable conditions than it does now. Stormy streams of rivers flowed across the surface of the planet; Mars had its own seas and lakes. Unfortunately, the planet does not have its own magnetic field and is much lighter than the Earth (its mass is about 10% of the Earth's). All this prevents Mars from maintaining a dense atmosphere. If the planet were heavier, perhaps we would now see life on it that would be as beautiful and diverse as on Earth.

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Conclusion

Science is exploring space by leaps and bounds. Everything we know today will help us find answers to many questions tomorrow.

We hope that in this century humanity will find extraterrestrial life. It was an article “TOP 7 places in the Universe where life is possible.” Thank you for your attention.

When I was a student in the 1960s, virtually all scientists were of the opinion that we were alone in the Universe. The search for intelligent life beyond the earth was ridiculed: it was believed that one could just as easily search for fairies. At the heart of the skepticism was the concept of the origin of life, which was generally believed to have arisen as a result of a random chemical reaction so unlikely that it simply could not happen twice. "The Origin of Life on this moment“It seems almost like a miracle,” wrote Francis Crick, “so many conditions had to be fulfilled for it to arise.” Jacques Monod agreed: in his 1976 book Chance and Necessity, he wrote: “Man has finally learned that he is alone in the indifferent immensity of the Universe in which he himself has appeared by pure chance.”

However, today the pendulum has swung decisively in the opposite direction. Many eminent scientists claim that the universe is filled with biological life, and at least some of this life is intelligent. Biologist Christian de Duve went so far as to call life a “cosmic imperative.” However, the quality and quantity of scientific evidence has remained largely unchanged. Today we know almost as much about the transition from lifeless to living as Darwin knew when he wrote: “It is now pointless to speculate about the origin of life; we might as well speculate about the origin of matter.”

Context

Second life for nuclear weapons

How to recognize alien life?

Is the universe alive?

The universe is hospitable

I am often asked how likely it is that we will be able to find intelligent life beyond Earth. But this question makes no sense. Since we know nothing about the process by which a mixture of chemical elements could turn into living cell in all its amazing complexity, it is simply impossible to calculate the likelihood of such a thing happening. It is impossible to calculate the probability of an unknown process. However, astrobiologists are apparently preoccupied with calculating the chances that a microbial life form will sooner or later evolve into an intelligent form. Although biologists cannot calculate this either, they at least understand this process: we are talking about Darwinian evolution. But it turns out that we are putting the cart before the horse. It is precisely the first step, that is, the moment of the birth of a microbial form of life, that remains the most foggy and unclear.

Carl Sagan once noted that the process of the origin of life cannot be too complex, otherwise it would not have appeared so soon after the Earth became a habitable planet. Of course, we cannot verify the presence of life on Earth 3.5 billion years ago. However, in making his argument, Sagan did not take into account the fact that we ourselves are a product of the earthly biological life that we study. If life had not arisen on Earth quickly enough, humans would not have evolved before the Sun dried out our planet. Because of this inevitable selection bias, we cannot draw statistically significant conclusions from just one sample.

Another very common argument is that the Universe is so vast that life must be present in one or more corners of it. If we limit ourselves to only the visible part of the Universe, then there are about 1023 planets in it. This is a very significant number. However, even this pales in comparison to the probability of the impossibility of the random occurrence of even the simplest organic molecules. If the path from chemistry to biology is so long and complex, it is likely that the chance of life emerging on one of the planets in our Universe will be equal to one in hundreds of trillions.

Claims that life in our universe may exist on many planets are based on the implicit belief that biological life is not the result of random chemical reactions, but rather a product some kind of purposeful self-organization - a kind of principle of life in action. Perhaps such a principle does exist, but even if so, we have not yet found any evidence for it.

Perhaps we shouldn't look that far. If life in a finished form arose in the shortest possible time, as Sagan suggested, this means that it must have arisen on our planet more than once. If life on earth arose several times, the microbial descendants of those life forms that arose at other times should be around us, making up a kind of shadow biosphere. So far, no one has seriously tried to look for life forms on our planet that may be unknown to us. Only after we discover one “foreign” microorganism will we begin to seriously address this issue.

Modern technologies are bringing humanity closer to solving this question. But only a little. Today, with the help of SETI - the Search for Extra Terrestrial Intelligence (search for extraterrestrial intelligence), as well as using radio telescopes, signals from extraterrestrial civilizations are being searched. The system, however, is characterized by passivity, when researchers have to sit with their hands folded and wait by the sea for weather. And so far this method has led to nothing.

But there is another method, more effective. SETI will use a collection of telescopes, including the famous 305-meter Arecibo telescope, to search for nearby stars to send electronic signals that could reveal whether there is intelligent life in those systems. And if a civilization living somewhere out there uses the same methods to work with exoplanets, then the SETI team will be able to detect the signals.

By and large, a project is being launched that is somewhat different from SETI, called METI. Messaging Extra Terrestrial Intelligence or Sending messages to extraterrestrial intelligence is actively sending messages to certain places in space, which can serve as a kind of greeting to potentially alien astronomers living somewhere.

But some scientists consider the project quite dangerous. For example, the famous physics theorist Stephen Hawking said that by informing aliens that we exist, we could bring disaster to us and our planet. A story similar to the voyage of Columbus and his landing in America may happen. Another mind may perceive humanity as an underdeveloped part of life. And this will lead to the same thing that happened to the Indians after the Old World learned of their existence.

Another researcher, Douglas Vakoch, assures that all the concerns are too far-fetched. The fact is that if there are such aliens who can travel throughout cosmic space, then they already have the ability to catch our TV, radio and other signals. So, if someone wanted to attack us, they would have done it a long time ago.

The question then arises: why keep sending signals? Yes, for the sake of science. After all, perhaps somewhere there live the same advanced forms of life as we do. And it's nice to know that they are not alone. In other words, as Douglas Vakoch says, the zoo theory can be tested. According to this scheme, it turns out that the presence of intelligent life is more widespread in the Universe than we can even imagine. Why then, for example, is there no signal from nearby star systems? Perhaps they are simply waiting for someone else to take the initiative.

Moreover, Douglas Vakoch believes that signals do not need to be sent very far. When it can take up to five thousand years to receive a signal. We need to explore the nearest stars, in case we have neighbors.

For the evolution of living organisms from the simplest forms (viruses, bacteria) to intelligent beings, huge intervals of time are required, since “ driving force” such selection are mutations and natural selection - processes that are random in nature. It is through a large number of random processes that the natural development from lower to higher forms of life is realized. Using the example of our planet Earth, we know that this time interval apparently exceeds a billion years. Therefore, only on planets orbiting sufficiently old stars can we expect the presence of highly organized living beings. At current state In astronomy, we can only talk about arguments in favor of the hypothesis of the multiplicity of planetary systems and the possibility of the emergence of life on them. Astronomy does not yet have rigorous proof of these most important statements. In order to talk about life, we must at least assume that fairly old stars have planetary systems. For the development of life on the planet, it is necessary that a number of conditions be met general. And it is quite obvious that life cannot arise on every planet.

We can imagine around every star that has a planetary system, a zone where temperature conditions do not exclude the possibility of the development of life. It is unlikely to be possible on planets like Mercury, the temperature of the part illuminated by the Sun is higher than the melting point of lead, or like Neptune, whose surface temperature is -200°C. However, one cannot underestimate the enormous adaptability of living organisms to unfavorable conditions external environment. It should also be noted that very high temperatures are much more “dangerous” for the life of living organisms than low ones, since the simplest types of viruses and bacteria can, as is known, be in a state of suspended animation at temperatures close to absolute zero.

In addition, it is necessary that the radiation of the star remains approximately constant over many hundreds of millions and even billions of years. For example, extensive class variable stars, whose luminosities vary greatly with time (often periodically), should be excluded from consideration. However, most stars radiate with amazing constancy. For example, according to geological data, the luminosity of our Sun has remained constant over the past few billion years with an accuracy of several tens of percent.

For life to appear on a planet, its mass should not be too small. On the other hand, too much mass is also an unfavorable factor; on such planets the probability of the formation of a solid surface is low; they are usually gas balls with a density rapidly increasing towards the center (for example, Jupiter and Saturn). One way or another, the masses of planets suitable for the development of life must be limited both above and below. Apparently, the lower limit of the mass possibilities of such a planet is close to several hundredths of the Earth’s mass, and the upper limit is tens of times greater than the Earth’s. Very great importance has the chemical composition of the surface and atmosphere. As you can see, the limits of the parameters of planets suitable for life are quite wide.

To study life, you must first define the concept of “living matter.” This question is far from simple. Many scientists, for example, define living matter as complex protein bodies with ordered metabolism. This point of view was held, in particular, by Academician A.I. Oparin, who worked a lot on the problem of the origin of life on Earth. Of course, metabolism is the most essential attribute of life, but the question of whether the essence of life can be reduced primarily to metabolism is controversial. After all, in the inanimate world, for example, in some solutions, metabolism is observed in its simplest forms. The question of defining the concept of “life” is very acute when we discuss the possibilities of life on other planetary systems.

Nowadays life is not defined through internal structure and the substances that are inherent in it, and through its functions: a “control system”, which includes a mechanism for transmitting hereditary information that ensures safety to subsequent generations. Thus, due to the inevitable interference in the transmission of such information, our molecular complex (organism) is capable of mutations, and therefore of evolution.

The emergence of living matter on Earth (and, as can be judged by analogy, on other planets) was preceded by a rather long and complex evolution of the chemical composition of the atmosphere, which ultimately led to the formation of a number of organic molecules. These molecules subsequently served as “building blocks” for the formation of living matter.

According to modern data, planets are formed from a primary gas-dust cloud, the chemical composition of which is similar chemical composition The sun and stars, their original atmosphere consisted mainly of the simplest compounds of hydrogen - the most common element in space. The majority of the molecules were hydrogen, ammonia, water and methane. In addition, the primary atmosphere should have been rich in inert gases - primarily helium and neon. Currently, there are few noble gases on Earth since they once dissipated (evaporated) into interplanetary space, like many hydrogen-containing compounds.

However, apparently decisive role Plant photosynthesis, which releases oxygen, played a role in establishing the composition of the earth's atmosphere. It is possible that some, and perhaps even a significant, amount of organic matter was brought to Earth by the fall of meteorites and, perhaps, even comets. Some meteorites are quite rich in organic compounds. It is estimated that over 2 billion years, meteorites could have brought to Earth from 108 to 1012 tons of such substances. Also, organic compounds can arise in small quantities as a result of volcanic activity, meteorite impacts, lightning, and due to the radioactive decay of certain elements.

There is fairly reliable geological evidence indicating that already 3.5 billion years ago the earth's atmosphere was rich in oxygen. On the other hand, the age of the earth's crust is estimated by geologists at 4.5 billion years. Life must have arisen on Earth before the atmosphere became rich in oxygen, since the latter is mainly a product of plant life. According to a recent estimate by the American planetary astronomer Sagan, life on Earth arose 4.0-4.4 billion years ago.

The mechanism of increasing complexity of the structure of organic substances and the appearance in them of properties inherent in living matter has not yet been sufficiently studied, although great successes have recently been observed in this area of ​​biology. But it is already clear that such processes last for billions of years.

Any no matter how complex combination of amino acids and other organic compounds is not yet a living organism. One can, of course, assume that under some exceptional circumstances, somewhere on Earth a certain “proto-DNA” arose, which served as the beginning of all living things. However, this is unlikely to be the case if the hypothetical “proto-DNA” was quite similar to modern DNA. The fact is that modern DNA by itself is completely helpless. It can function only in the presence of enzyme proteins. To think that purely by chance, by “shaking up” individual proteins - polyatomic molecules, such a complex machine as “praDNA” and the complex of protein-enzymes necessary for its functioning could arise - this means believing in miracles. However, it can be assumed that DNA and RNA molecules evolved from a more primitive molecule.

For the first primitive living organisms formed on the planet, high doses of radiation could pose a mortal danger, since mutations would occur so quickly that natural selection could not keep up with them.

Another question that deserves attention is: why doesn’t life on Earth arise from nonliving matter in our time? This can only be explained by the fact that previously existing life will not provide the opportunity for a new birth of life. Microorganisms and viruses will literally eat the first sprouts of new life. The possibility that life on Earth arose by chance cannot be completely ruled out.

There is one more circumstance that may be worth paying attention to. It is well known that all “living” proteins consist of 22 amino acids, while over 100 amino acids are known in total. It is not entirely clear how these acids differ from the rest of their “brothers”. Is there some deep connection between the origin of life and this amazing phenomenon?

If life on Earth arose by chance, it means that life in the Universe is a rare (although, of course, by no means an isolated) phenomenon. For a given planet (such as our Earth), the emergence of a special form of highly organized matter, which we call “life,” is an accident. But in the vast expanses of the Universe, life arising in this way should be a natural phenomenon.

It should be noted once again that the central problem of the emergence of life on Earth - the explanation of the qualitative leap from “non-living” to “living” - is still far from clear. It is not without reason that one of the founders of modern molecular biology, Professor Crick, said at the Byurakan Symposium on the problem of extraterrestrial civilizations in September 1971: “We do not see a path from the primordial soup to natural selection. One may come to the conclusion that the origin of life is a miracle, but this only testifies to our ignorance.”

The exciting question of life on other planets has occupied the minds of astronomers for several centuries. The possibility of the very existence of planetary systems around other stars is only now becoming a subject scientific research. Previously, the question of life on other planets was an area of ​​purely speculative conclusions. Meanwhile, Mars, Venus and other planets of the solar system have long been known as non-self-luminous solid celestial bodies surrounded by atmospheres. It has long become clear that in general terms they resemble the Earth, and if so, why shouldn’t there be life on them, even highly organized, and, who knows, intelligent?

It is quite natural to believe that the physical conditions that prevailed on the terrestrial planets (Mercury, Venus, Earth, Mars) that had just formed from a gas-dust environment were very similar, in particular, their initial atmospheres were the same.

The main atoms that make up the molecular complexes from which living matter is formed are hydrogen, oxygen, nitrogen and carbon. The role of the latter is especially important. Carbon is a tetravalent element. Therefore, only carbon compounds lead to the formation of long molecular chains with rich and variable side branches. Various protein molecules belong to this type. Silicon is often called a carbon substitute. Silicon is quite abundant in space. In the atmospheres of stars, its content is only 5-6 times less than carbon, that is, it is quite high. It is unlikely, however, that silicon can play the role of a “cornerstone” of life. For some reason, its compounds cannot provide as much variety of side branches in complex molecular chains as carbon compounds. Meanwhile, the richness and complexity of such side branches is precisely what provides a huge variety of properties of protein compounds, as well as the exceptional “information content” of DNA, which is absolutely necessary for the emergence and development of life.

The most important condition for the origin of life on the planet is the presence of a sufficiently large amount of liquid Medium on its surface. In such an environment, organic compounds are in a dissolved state and favorable conditions can be created for the synthesis of complex molecular complexes based on them. In addition, a liquid environment is necessary for newly emerged living organisms to protect them from the harmful effects of ultraviolet radiation, which at the initial stage of the planet’s evolution can freely penetrate to its surface.

It can be expected that such a liquid shell can only be water and liquid ammonia, many compounds of which, by the way, are similar in structure to organic compounds, due to which the possibility of the emergence of life on an ammonia basis is currently being considered. The formation of liquid ammonia requires a relatively low temperature of the planet's surface. In general, the temperature of the original planet is very important for the emergence of life on it. If the temperature is high enough, for example above 100°C, and the atmospheric pressure is not very high, a water shell cannot form on its surface, not to mention ammonia. Under such conditions, there is no need to talk about the possibility of the emergence of life on the planet.

Based on the above, we can expect that the conditions for the emergence of life on Mars and Venus in the distant past could, generally speaking, be favorable. The liquid shell could only be water, and not ammonia, as follows from an analysis of the physical conditions on these planets during the era of their formation. Currently, these planets are quite well studied, and nothing indicates the presence of even the simplest forms of life on any of the planets of the solar system, not to mention intelligent life. However, it is very difficult to obtain clear indications of the presence of life on a particular planet through astronomical observations, especially if we are talking about a planet in another star system. Even with the most powerful telescopes, under the most favorable observation conditions, the size of the features still visible on the surface of Mars is 100 km.

Before this, we only determined the most general conditions under which life can (not necessarily must) arise in the Universe. Such complex shape matter, like life, depends on large number completely unrelated phenomena. But all these arguments concern only the simplest forms of life. When we move on to the possibility of certain manifestations of intelligent life in the Universe, we are faced with very great difficulties.

Life on any planet must undergo a huge evolution before becoming intelligent. The driving force behind this evolution is the ability of organisms to mutate and natural selection. In the process of such evolution, organisms become more and more complex, and their parts become specialized. Complications occur in both qualitative and quantitative directions. For example, a worm has only about 1000 nerve cells, while humans have about ten billion. Development nervous system significantly increases the ability of organisms to adapt and their plasticity. These properties of highly developed organisms are necessary, but, of course, not sufficient for the emergence of intelligence. The latter can be defined as the adaptation of organisms to their complex social behavior. The emergence of intelligence must be closely connected with a radical improvement and improvement in the ways of exchanging information between individuals. Therefore, for the history of the emergence of intelligent life on Earth, the emergence of language was of decisive importance. Can we, however, consider such a process universal for the evolution of life in all corners of the Universe? Most likely no! Indeed, in principle, under completely different conditions, the means of information exchange between individuals could not be longitudinal vibrations of the atmosphere (or hydrosphere) in which these individuals live, but something completely different. Why not imagine a way to exchange information based not on acoustic effects, but, say, on optical or magnetic ones? And in general, is it really necessary for life on some planet to become intelligent in the process of its evolution?

Meanwhile, this topic has worried humanity since time immemorial. When talking about life in the Universe, we always meant, first of all, intelligent life. Are we alone in the boundless expanses of space? Philosophers and scientists since ancient times have always been convinced that there are many worlds where intelligent life exists. No scientifically based arguments were given in favor of this statement. The reasoning, essentially, was carried out according to the following scheme: if there is life on Earth, one of the planets in the solar system, then why shouldn’t it be on other planets? This method of reasoning, if logically developed, is not so bad. And in general, it’s scary to imagine that out of 1020 - 1022 planetary systems in the Universe, in an area with a radius of tens of billions of light years, intelligence exists only on our tiny planet... But perhaps intelligent life is an extremely rare phenomenon. It may be, for example, that our planet, as the abode of intelligent life, is the only one in the Galaxy, and not all galaxies have intelligent life. Is it even possible to consider works on intelligent life in the Universe to be scientific? Probably, after all, with the current level of technological development, it is possible and necessary to deal with this problem now, especially since it may suddenly turn out to be extremely important for the development of civilization...

The discovery of any life, especially intelligent life, could be of great importance. Therefore, attempts have been made for a long time to discover and establish contact with other civilizations. In 1974, the automatic interplanetary station Pioneer 10 was launched in the United States. Several years later, she left the solar system, completing various scientific tasks. There is a negligible probability that someday, many billions of years from now, highly civilized alien beings unknown to us will discover Pioneer 10 and greet him as a messenger from an alien world unknown to us. For this case, there is a steel plate inside the station with a pattern and symbols engraved on it, which provide minimal information about our earthly civilization. This image is composed in such a way that intelligent beings who find it will be able to determine the position of the solar system in our Galaxy and guess our appearance and, possibly, our intentions. But of course, an extraterrestrial civilization has a much better chance of finding us on Earth than finding Pioneer 10.

The question of the possibility of communication with other worlds was first analyzed by Cocconi and Morris in 1959. They came to the conclusion that the most natural and practically feasible communication channel between any civilizations separated by interstellar distances could be established using electromagnetic waves. The obvious advantage of this type of communication is the propagation of the signal at the maximum speed possible in nature, equal to the speed of propagation of electromagnetic waves, and the concentration of energy within relatively small solid angles without any significant scattering. The main disadvantages of this method are the low power of the received signal and strong interference arising from vast distances and cosmic radiation. Nature itself tells us that transmissions should occur at a wavelength of 21 centimeters (the wavelength of free hydrogen radiation), while the loss of signal energy will be minimal, and the probability of receiving a signal by an extraterrestrial civilization is much greater than at a randomly chosen wavelength. Most likely, we should expect signals from space on the same wavelength.

But let's say that we have detected some strange signal. Now we must move on to the next, rather important issue. How to recognize the artificial nature of a signal? Most likely, it should be modulated, that is, its power should change regularly over time. At first, it should apparently be quite simple. After the signal is received (if, of course, this happens), two-way radio communication will be established between civilizations, and then more complex information can begin to be exchanged. Of course, we should not forget that answers may not be obtained earlier than in several tens or even hundreds of years. However, the exceptional importance and value of such negotiations should certainly compensate for their slowness.

Radio observations of several nearby stars have already been carried out several times as part of the large OMZA project in 1960 and using the telescope of the US National Radio Astronomy Laboratory in 1971. A large number of expensive projects for establishing contacts with other civilizations have been developed, but they are not funded, and very few actual observations have been made so far.

Despite the obvious advantages of space radio communications, we should not lose sight of other types of communications, since it is impossible to say in advance what signals we may be dealing with. Firstly, this is optical communication, the main disadvantage of which is the very weak signal level, because, despite the fact that the divergence angle of the light beam was brought to 10 -8 rad, its width at a distance of several light years will be enormous. Communication can also be carried out using automatic probes. For obvious reasons, this type of communication is not yet available to earthlings, and will not become available even with the beginning of the use of controlled thermonuclear reactions. When launching such a probe, we would be faced with a huge number of problems, even if we consider the time of its flight to the target to be acceptable. In addition, there are already more than 50,000 stars less than 100 light years from the solar system. Which one should I send the probe to?

Thus, establishing direct contact with extraterrestrial civilization on our part is still impossible. But maybe we should just wait? Here we cannot fail to mention the very pressing problem of UFOs on Earth. Various occasions So many “observations” of aliens and their activities have already been noticed that in no case can one unequivocally refute all this data. We can only say that many of them, as it turned out over time, were inventions or the result of an error. But this is a topic for other research.

If some form of life or civilization is discovered somewhere in space, then we absolutely, even approximately, cannot imagine what its representatives will look like and how they will react to contact with us. What if this reaction is, from our point of view, negative. Then it’s good if the level of development of extraterrestrial beings is lower than ours. But it may turn out to be immeasurably higher. Such contact, given a normal attitude towards us from another civilization, is of the greatest interest. But one can only guess about the level of development of aliens, and nothing at all can be said about their structure.

Many scientists are of the opinion that civilization cannot develop beyond a certain limit, and then it either dies or no longer develops. For example, the German astronomer von Horner named six reasons, in his opinion, that could limit the duration of the existence of a technically advanced civilization:

• 1) complete destruction of all life on the planet;
• 2) destruction of only highly organized beings;
• 3) physical or spiritual degeneration and extinction;
• 4) loss of interest in science and technology;
• 5) lack of energy for the development of a very highly developed civilization;
• 6) the lifetime is unlimited;

Von Horner considers this last possibility completely incredible. Further, he believes that in the second and third cases, another civilization can develop on the same planet on the basis (or on the ruins) of the old one, and the time of such “resumption” is relatively short.

From September 5 to September 11, 1971, the first international Conference on the problem of extraterrestrial civilizations and connections with them. The conference was attended by competent scientists working in various fields related to the complex problem under consideration - astronomers, physicists, radiophysicists, cybernetics, biologists, chemists, archaeologists, linguists, anthropologists, historians, sociologists. The conference was organized jointly by the USSR Academy of Sciences and the US National Academy of Sciences with the participation of scientists from other countries. At the conference, many aspects of the problem of extraterrestrial civilizations were discussed in detail. The questions of the multiplicity of planetary systems in the Universe, the origin of life on Earth and the possibility of the emergence of life on other space objects, the emergence and evolution of intelligent life, the emergence and development of technological civilization, the problems of searching for signals from extraterrestrial civilizations and traces of their activities, the problems of establishing communications with them, as well as possible consequences establishing contacts.