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Introduction

Elements of cosmology

CMB radiation

Elements of cosmogony

Formation of stars and galaxies

Star evolution

Origin of the solar system

Cosmogony according to Laplace

The theory of Academician O.Yu.Shmidt

Origin of life

Search for extraterrestrial civilizations

Philosophical and worldview problems of cosmological evolution

Conclusion

List of used literature

INTRODUCTION

What is the Earth, Moon, Sun, stars? Where is the beginning and where is the end of the Universe, how long does it exist, what does it consist of and where are the boundaries of its knowledge?

The study of the Universe, even only part of it known to us, is a daunting task. To obtain the information that modern scientists have, it took the work of many generations.

The stars in the universe are grouped into giant star systems called galaxies. The stellar system, in which our Sun is located as an ordinary star, is called the Galaxy.

The number of stars in the Galaxy is about 10 12 (trillion). The Milky Way, a bright silver band of stars, encircles the entire sky, making up the bulk of our galaxy. The Milky Way is brightest in the constellation Sagittarius, where the most powerful clouds of stars are found. It is least bright in the opposite part of the sky. From this it is easy to conclude that the solar system is not located in the center of the Galaxy, which is visible from us in the direction of the constellation Sagittarius. The farther from the plane of the Milky Way, the fewer faint stars there are and the less far the star system stretches in these directions. In general, our Galaxy occupies a space resembling a lens or lentil when viewed from the side. The dimensions of the Galaxy were outlined by the arrangement of stars that are visible at great distances. These are Cepheids and hot giants. The diameter of the Galaxy is approximately equal to 30,000 pc Parsec (pc) - the distance at which the semi-major axis of the Earth's orbit, perpendicular to the line of sight, is visible at an angle of 1". 1 Parsec = 3.26 light years = 206265 AU = 3*10 13 km. , but it does not have a clear boundary, because the stellar density is gradually fading away.

In the center of the Galaxy there is a core with a diameter of 1000-2000 pc - a giant dense cluster of stars. It is located at a distance of almost 10,000 pc from us in the direction of the Sagittarius constellation, but is almost completely hidden by a dense curtain of clouds, which prevents visual and ordinary photographic observations of this most interesting object of the Galaxy. The core contains many red giants and short-period Cepheids.

Upper main sequence stars, and especially supergiants and classical Cepheids, make up the younger population. It is located further from the center and forms a relatively thin layer or disk. Among the stars of this disk is dusty matter and clouds of gas. Subdwarfs and giants form a spherical system around the nucleus and disk of the Galaxy.

The mass of our Galaxy is now estimated in various ways, it is approximately 2 * 10 11 solar masses (the mass of the Sun is 2 * 10 30 kg), and 1/1000 of it is contained in interstellar gas and dust. The mass of the galaxy in Andromeda is almost the same, while the mass of the galaxy in Triangulum is estimated to be 20 times less. Our galaxy is 100,000 light years across. Through painstaking work, the Moscow astronomer V.V. Kukarin in 1944 found indications of the spiral structure of the Galaxy, and it turned out that we live in a space between two spiral branches, poor in stars. In some places in the sky with a telescope, and in some places even with the naked eye, one can distinguish close groups of stars connected by mutual gravity, or star clusters.

The Universe is evolving, turbulent processes took place in the past, are taking place now and will take place in the future.

ELEMENTS OF COSMOLOGY

The universe is everything that exists. From the smallest dust grains and atoms to huge accumulations of the matter of stellar worlds and stellar systems. Therefore, it will not be a mistake to say that any science in one way or another studies the Universe, more precisely, one way or another of its aspects. Chemistry studies the world of molecules, physics - the world of atoms and elementary particles, biology - the phenomena of living nature. But there is a scientific discipline whose object of study is the Universe itself. This is a special branch of astronomy, the so-called cosmology. Cosmology is the study of the Universe as a whole, including the theory of the entire area covered by astronomical observations as part of the Universe. By the way, one should not confuse the concepts of the Universe as a whole and the “observed” (visible) Universe. In the second case we are talking only about that limited area of ​​space that is available modern methods scientific research.

With the development of cybernetics in various fields scientific research modeling techniques have become very popular. The essence of this method lies in the fact that instead of one or another real object, its model is studied, which more or less exactly repeats the original or its most important and essential features. The model is not necessarily a real copy of the object. The construction of approximate models of various phenomena helps us to learn more and more deeply the world. For example, for a long time, astronomers have been studying an imaginary homogeneous and isotropic universe in which everything physical phenomena flow in the same way and all laws remain unchanged for any area and in any direction. Models were also studied in which a third condition was added to these two conditions - the immutability of the picture of the world. This means that in whatever era we contemplate the world, it should always look the same in general terms. These largely conditional and schematic models helped to illuminate some important aspects of the world around us. But no matter how complex this or that theoretical model is, no matter how diverse facts it takes into account, any model is not the phenomenon itself, but only a more or less exact copy of it. Therefore, all results obtained with the help of models of the Universe must be verified by comparison with reality. This indicates the need for in-depth development of models of an inhomogeneous and nonisotropic Universe.

In the Middle Ages, many scientists believed that the universe was finite and limited to the sphere of fixed stars. Even N. Copernicus and T. Brahe adhered to this point of view.

With the development of science, which more and more fully reveals the physical processes taking place in the world around us, most scientists gradually switched to materialistic ideas about the infinity of the Universe. Here great value had the discovery by I. Newton (1643 - 1727) of the law of universal gravitation, published in 1687. One of the important consequences of this law was the assertion that in a finite universe all its matter in a limited period of time should be drawn into a single close system, while in an infinite Universe matter under the influence of gravity is collected in some limited volumes (according to the ideas of the time - in the stars), uniformly filling the Universe.

Of great importance for the development of modern ideas about the structure and development of the Universe is the general theory of relativity, created by A. Einstein (1879 - 1955). It generalizes Newton's theory of gravitation to large masses and speeds comparable to the speed of light. Indeed, a colossal mass of matter is concentrated in galaxies, and the speeds of distant galaxies and quasars are comparable to the speed of light.

One of the significant consequences general theory relativity is the conclusion about the continuous movement of matter in the universe - the non-stationarity of the universe. This conclusion was obtained in the 1920s by the Soviet mathematician A.A. Fridman (1888 - 1925). He showed that, depending on the average density of matter, the universe must either expand or contract. With the expansion of the Universe, the speed of the recession of galaxies should be proportional to the distance to them - a conclusion confirmed by Hubble by the discovery of redshift in the spectra of galaxies.

The critical value of the average density of a substance, on which the nature of its movement depends,

where G is the gravitational constant and H=75 km/s*Mpc is the Hubble constant.

Substituting the desired values, we obtain that the critical value of the average density of the substance is g/cm 3 .

If the average density of matter in the Universe is greater than the critical one, then in the future the expansion of the Universe will be replaced by contraction, and if the average density is equal to or less than the critical one, the expansion will not stop. Of course, we do not know the average density of matter in the entire Universe, but we can calculate this density in the part of the Universe accessible to our study, i.e. in the Metagalaxy. It is equal to 2.6 * 10 -30 g / cm 3, which is approximately 4 times less than the critical density. But it is still premature to draw conclusions about the infinitely expanding Universe, because some astronomers are suggesting the existence of matter in galaxies, which has not yet been discovered. This "hidden mass" can change the estimate of the currently accepted average density of matter in the Universe. Therefore, there is currently no exact answer to the question about the future of the Universe.

Modern cosmology believes that in the distant past, about 13 billion years ago, all the matter of the Metagalaxy was concentrated in a small volume and the density of the matter was so high that neither galaxies nor stars existed. So far, neither the physical processes that took place before this superdense state of matter, nor the reasons that caused the expansion of the Universe are clear. One thing is clear, that over time, the expansion led to a significant decrease in the density of matter, and at a certain stage of the expansion, galaxies and stars began to form.

General ideas about the physical conditions in the early stages of the expansion of the Metagalaxy can be obtained from an analysis of the chemical composition of matter. One of the most important consequences of this analysis was the discovery of relic studies.

CMB radiation

The main advantage of any theory is its predictive power. In cosmology until the mid-60s. there were two competing theories: the model of the "hot" Universe and the model of the "cold" Universe. The first of them was developed by the outstanding scientist G. Gamow (one cannot say "outstanding physicist" because, although physics was his main specialty, he made a great contribution to both astrophysics and biology) and his collaborators.

This model assumes that in the early stages of the evolution of the Universe, not only the density of matter, but also its temperature was extremely high. The theory was developed primarily to explain the chemical composition of the universe, and this goal was achieved. The most important prediction of the theory was the existence of radiation with a thermal spectrum. This radiation has come down to us from that distant era when the Universe was very dense and hot, however, over many billions of years, this radiation should have noticeably "cooled down". This cooling is associated with the expansion of the Universe, during which the temperature decreased according to the adiabatic law.

But, as sometimes happens, this relic of the early Universe was discovered not as a result of systematic research, but almost by accident. This discovery was made in 1965 by A. Penzias and R. Wilson, and in 1978 they were awarded the Nobel Prize in Physics for the discovery of cosmic microwave background radiation.

The relic, or microwave background, radiation has a thermal spectrum corresponding to a temperature of 2.7 K. This corresponds to a temperature of 4000 K at which recombination occurred, taking into account the redshift z=1500 (electrons and ions combined into atoms, i.e. recombined after 100,000 years after the start of the expansion).

When people say that the CMB has a thermal spectrum, it means that the spectrum looks like there is an opaque wall at a great distance, heated to a temperature of 2.7 degrees Kelvin.

Relic photons are extremely numerous. One cubic centimeter contains approximately 500 such photons. This is a billion times greater than the concentration of baryons, i.e. "ordinary" matter. The objects around us are composed of atoms, the bulk of which is concentrated in the nucleus. The atomic nucleus consists of two types of elementary particles: protons and neutrons. Such particles are called baryons. Therefore, all the matter surrounding us, as well as the matter of planets, stars, is called baryonic matter. But due to the low energy of photons, their contribution to the density of the Universe is now small (1000 times less than the contribution of "ordinary", baryonic matter). However, before the situation was different. In an era when the radiation temperature was much higher, it was radiation that played the main role in the Universe.

And now the relic radiation affects some cosmic processes. For example, back in 1941, it was discovered that the lower energy levels of the CN molecule are excited as if they were in a radiation field with a temperature of several degrees Kelvin. This is due to the influence of microwave background radiation, and it could have been discovered in this way almost 25 years earlier.

Relic photons can also form new particles as a result of collisions with cosmic ray particles, thus "eating away" particles with high energies (E>10 20 eV).

Microwave background radiation has a large isotropy, i.e. after taking into account corrections due to the movement of the observer (the rotation of the Earth around the Sun, the rotation of the Sun around the center of the Galaxy and the movement of the Galaxy itself), its temperature measured in different parts of the sky is the same with a high degree of accuracy.

It follows from the theory that a slight anisotropy must still exist. After all, matter is evenly distributed only on scales of the order of a billion light years. The inhomogeneities associated with the formation of clusters and superclusters of galaxies could not but be reflected in the background radiation. Therefore, anisotropy must also exist in the temperature distribution of the cosmic microwave background radiation in the sky, i.e. dT, temperature difference, is not zero. And in 1992 such anisotropy was discovered! This was done using observations on the COBE and Relikt-1 satellites.

Small detected irregularities (fluctuations) responsible for the formation of galaxy clusters with dimensions of tens of megaparsecs came to us from that era when the Universe was only 10 -35 sec. and it was at the stage of inflation.

The discovery and study of the cosmic microwave background radiation made it possible to make a big step in understanding the structure of the Universe and its evolution. New research is ongoing in this direction.

ELEMENTS OF COSMOGONY

The section of astronomy that studies the origin and development (evolution) of galaxies, stars and the solar system is called cosmogony (from the Greek "cosmos" - the world and "gonos" - the origin).

Astronomical observations prove that matter in the Universe is in continuous development, in a wide variety of forms and states - from gas and dust of negligible density to superdense objects, from dwarf to supergiant stars of sharply different sizes and luminosities, from relatively small stellar groups to colossal the size and variety of shapes of galaxies, which are also at different stages of their development. Since the forms of existence of matter change, then, consequently, the various and diverse objects of the Universe could not all arise at the same time, but were formed in different epochs and therefore has its own specific age, counted from the beginning of their generation.

The disclosure of the patterns of origin and evolution of various objects of the Universe is part of the tasks of cosmogony. She solves these problems by developing scientific assumptions (hypotheses) based on astronomical observations and their theoretical generalization, using the achievements of all branches of natural science. Therefore, in the process of the development of natural science, as it is enriched with scientific discoveries, new cosmogonic hypotheses are developed to explain the newly discovered facts, and the old ones that do not satisfy them are rejected.

Modern cosmogony in its generalizations relies on the achievements of related branches of natural science - physics, mathematics, chemistry, geology.

Formation of stars and galaxies

The scientific foundations of cosmogony were laid by N. Newton, who showed that the uniform distribution of matter in space is unstable and, under the influence of its own gravity, must be divided into contracting clumps. The theory of the formation of clumps of matter from which stars are formed was developed in 1902 by the English astrophysicist J. Jeans (1877 - 1946). This theory also explains the process of formation of galaxies. Jeans proved that compaction can occur in an initially homogeneous gaseous medium with a constant density and temperature. If the force of mutual gravitation in it exceeds the force of gas pressure, then the medium will cease to compress, and if gas pressure prevails, then the substance will dissipate in space.

This theory is broadly supported by observations. Thus, in the Galaxy, the interstellar medium (gas and dust) is inhomogeneous and has a ragged structure. In relatively small gas clouds with a mass close to the mass of the Sun, the force of gas pressure is balanced by the force of gravity, and the clouds do not compress. In large gas and dust nebulae, similar to the Great Nebula of Orion and called gas and dust complexes, 10 - 100 pc in size and weighing several thousand solar masses, the force of gravity prevails over the force of gas pressure. Therefore, clumps of matter appear in such clouds, the temperature inside of which rises during compression, and they gradually transform into stars. Consequently, in gas and dust complexes, stars form in groups, forming star clusters and associations. The formation of stars in groups even in our era was first pointed out back in 1947 by the Soviet astrophysicist V.A. Ambartsumyan.

The emergence of galaxies can be explained in a similar way, for the formation of which the conditions were favorable at the early stages of the expansion of the Metagalaxy, when the temperature of the substance was close to 10 6 K. Colossal clumps with masses of the order of hundreds of billions of solar masses, called protogalaxies, were formed. As they were further compressed, conditions arose in them for the formation of stars, i.e. formed star systems - galaxies.

Based on the fact of the expansion of the Metagalaxy, some specialists in the field of cosmology estimate its age by the reciprocal of the Hubble constant, i.e. 1.3*10 10 years. Considering that the currently accepted value of the Hubble constant is known with little accuracy, the age of the Metagalaxy is considered to be close to 13 - 15 billion years. This age does not contradict the age estimates for the oldest stars and globular star clusters in our Galaxy.

Star evolution

Condensations that have arisen in the gas and dust environment of the Galaxy and continue to shrink under the influence of their own gravity are called protostars. As the protostar shrinks, its density and temperature increase, and it begins to radiate abundantly in the infrared range of the spectrum. The duration of the stage of contraction of protostars is different: for masses less than solar - hundreds of millions of years, and for massive ones - only hundreds of thousands of years. When the temperature in the interior of a protostar rises to several million kelvins, thermal nuclear reactions converting hydrogen to helium. In this case, huge energy is released, preventing further compression and heating the substance to self-luminescence - the protostar turns into an ordinary star.

After hydrogen burns out, a helium core is formed in the interior of the star, and thermonuclear reactions of the conversion of hydrogen into helium begin to occur in a thin layer near the boundary of the core. In the helium core itself, at the created temperature, nuclear reactions cannot occur, and it is sharply compressed to a density of over 4 * 10 6 kg / m 3. Due to compression, the temperature in the core increases. The rise in temperature depends on the mass. For stars like the Sun, the core temperature always remains below 80 million kelvins. Therefore, its compression leads only to a more rapid release of nuclear energy in a thin layer near the boundary of the nucleus. In more massive stars, the core temperature during compression becomes higher than 80 million kelvins, and thermonuclear reactions begin in it, converting helium into carbon, and then into other heavier chemical elements. The energy escaping from the core and its environs causes an increase in gas pressure, under the influence of which the star's photosphere expands. The energy coming to the photosphere from the interior of the star now spreads over a larger area than before. As a result, the temperature of the photosphere decreases. The star gradually turns into a red giant or supergiant depending on the mass, and becomes an old star. Passing through the stage of a yellow supergiant, the star may turn out to be pulsating, i.e. a physical variable star, and remain in such a red supergiant stage.

The swollen shell of a star of small mass is already weakly attracted by its core and, gradually moving away from it, forms a planetary nebula. After the final scattering of the shell, only the hot core of the star remains - a white dwarf.

The evolution of massive stars is more rapid. At the end of its life, such a star can explode into a supernova, and its core, having contracted sharply, will turn into a superdense object - a neutron star or even a black hole. The ejected shell, enriched with helium and other chemical elements formed in the interior of the star, dissipates in space and serves as material for the formation of new generation stars. Consequently, some characteristic differences in the content of heavy chemical elements in stars can also serve as a sign of their formation and age.

Origin of the solar system

Cosmogony according to Laplace

Knowing the past of the Earth is practically important for understanding the structure and changes in its interior, and the latter is important in the search for minerals and for the ability to predict earthquakes.

When establishing the history of the development of perennial organisms, we can compare their different specimens. Oaks and oak trees, rotten trees tell us about the life path of centuries-old trees, of which none of them completes it completely before our eyes. One can compare the planets in their current state with each other and try to judge the evolution of the Earth from them. But we have nothing to compare our solar system with, because we do not know others like it.

The philosopher Kant in the middle of the 18th century clearly expressed the idea of ​​the evolution of world bodies and, ahead of astronomers, sketched a conceivable picture of the emergence of the solar system from a vast nebula. He drew it in accordance with what was then known to science about the structure of the solar system, planets and nebulae, about the laws of nature.

Kant boldly rejected the idea of ​​creation and depicted the development of the worlds as occurring due to the natural laws of nature.

Independently of Kant, the mathematician, mechanic, and astronomer Laplace developed a similar picture of the origin of the solar system. His reasoning was stricter and more scientific. The ideological significance of these works by Kant and Laplace was very great. Contemporaries were shocked by the majestic picture of the universe developed by Laplace.

These works, as well as the development of the idea of ​​evolution, in particular in the field of geology, by the great Russian scientist M.V. Lomonosov contributed to the fact that later scientists in other fields of science were convinced of the existence of development in nature. The concept of evolution gradually entered other sciences.

Laplace, like Kant, correctly noted the main characteristic features of the solar system known at that time, which the theory of their origin should explain. These traits are:

The vast majority of the mass of the system is concentrated in the Sun.

The planets revolve in almost circular orbits in almost the same plane.

All planets turn in the same direction; in the same direction, their satellites revolve around the planets and the planets themselves rotate around their axis.

At the time of Laplace, it was already realized that regular rotation could not arise from a completely chaotic motion of particles, contrary to Kant's assumption. Therefore, Laplace begins his consideration of the development of the solar system with a giant gaseous nebula, already rotating around its axis, albeit very slowly.

It rotated like a solid body and had a clot in the center - the embryo of the future Sun. Attraction to the center of the particles of the nebula, which first extended beyond the orbit of the most distant of the planets, forced it to contract. Reducing the size according to the laws of mechanics should have led to an acceleration of rotation. There came a moment when, at the equator of the nebula, where the linear speeds of particles during rotation are greatest, the centrifugal force was equalized with gravity towards the center. At that moment, a gas ring peeled off along the equator of the nebula, rotating in the same direction as the nebula was rotating. Continued compression and acceleration of rotation led to the detachment of ring after ring. Due to the inevitable inhomogeneity of each ring, any clot in it attracted the rest of the substance of the ring, and one gas ball was formed - the future planet. The outer parts of the ring, and subsequently the clot, ran as if forward during circulation and brought it into rotation around the axis in the same direction as the planet's embryo was moving.

When the clots were compressed due to gravity, they themselves could peel off the rings and give rise to satellites for themselves. If in such a ring there was no sharply predominant clot, "devouring" the rest, then it was broken into many small bodies; so, for example, the ring of Saturn was formed. Cooling, the gas clumps solidified, covered with a crust and turned into modern planets, and the central clot gave birth to the Sun.

The captivating simplicity and logicality of this scheme (the former generally recognized for more than a century) were subsequently opposed by the most serious objections. For example, the following circumstances, unknown at the time of Laplace, came to light:

The density of Laplace's imaginary gaseous nebula must have been so low that it could not rotate like a solid body.

The detachment of matter would not occur in rings, but continuously.

Rings with a mass equal to the mass of the planets could not condense, but would disperse into space.

There are planets and satellites that rotate or turn towards the rotation of the planets around the Sun.

One of the satellites of Mars revolves around the planet faster than Mars itself, which cannot be according to Laplace's theory.

A number of other theoretical objections to Laplace's theory also arose.

Many have tried to correct this theory, but to no avail. Science better understood the properties of the solar system and the laws of nature - we had to look for a new explanation for the origin of this system.

In 1919, the English astrophysicist Jeans suggested that the solar system is a game of a rare case of the Sun's approach to any star.

Having passed close to the Sun in the distant past and again disappeared into the unknown distance, the incoming star excited a powerful tidal wave on the Sun. The matter attracted by it escaped from the Sun and reached for the star in a long stream, in the form of a cigar. The sun already then consisted of dense gases, so that, being dense, they did not dissipate, but cooled and, having frozen, formed planets. However, as the American astronomer Ressel showed, most of the matter ejected from the Sun would either fall back on it or be carried away after the departing star, but would not form anything resembling the existing system of planets.

Modern hypotheses about the origin of the solar system cannot take into account only the mechanical characteristics of the solar system. They must also take into account numerous physical data on the structure of the planets and the Sun, which was especially convincingly shown in the works of Acad. VG Fesenkov, who developed the issues of cosmogony for 35 years.

galaxy solar relic space

The theory of Academician O.Yu.Shmidt

The theory, the foundations of which were laid by Academician O.Yu.Shmidt, is the most developed, and therefore I am citing it.

O.Yu.Shmidt first proceeded from the fact that meteoritic matter, both in the form of more or less large pieces, and in the form of dust, is found in abundance in the Universe. Until recently, this meteorite substance was known to us only within the solar system, but now we find it in huge quantities and in interstellar space. For the most part, meteorite matter is collected in colossal cosmic clouds - in diffuse light and dark nebulae, which also contain a lot of gas.

Subsequently, various considerations led the Soviet scientists L.E. Gurevich and A.I. Lebedinsky to the conclusion that the pre-planetary substance was of a gas-dust composition. O.Yu. Schmidt agreed with this idea of ​​the state of pre-planetary matter, but emphasized that the “leading role” belongs to dust.

The totality of gas and dust clouds, together with stars, fills our stellar system - the Galaxy, and their substance is strongly concentrated towards the plane of its symmetry - towards the plane of the Galaxy's equator. Together with stars, gas-dust clouds participate in the rotation of the Galaxy around its axis. Along with this rotation around the center of the Galaxy, both stars and gas-dust clouds have their own movements, which lead to the fact that both stars and clouds either approach each other or diverge. Sometimes one or another star plunges for a time into a gas-dust nebula and makes its way through it. Many dust particles fall on the star during its gliding through the nebula, while others, having changed their orbits due to the powerful attraction of the star, can be captured by it and become its satellites. However, for such a capture to occur, special favorable conditions are necessary - a decrease in the relative velocity of dust particles due to attraction by a nearby star or, as T.A. Agekyan showed, due to the collision of dust grains with each other. In such a "successful" case, a huge number of these satellites of the star, according to Schmidt's hypothesis, do not leave it even after leaving the nebula. The star is surrounded by a huge cloud of particles of gas and dust, describing various orbits around it. Later, O.Yu. Schmidt believed that the capture of a cloud from the very diffuse medium from which the Sun itself arose could be more probable.

The cloud that formed around the stars gradually took on a lenticular shape. The circulation of particles in it around the star occurred mainly, although not exclusively, in one direction (at small angles to each other), because the dust layer penetrated by the star. Could not be completely uniform.

In a similar star, surrounded by a lenticular gas-dust cloud, O.Yu. Schmidt saw our Sun, at a time that preceded the formation of planets.

In a host of dust particles circulating around the Sun along intersecting and differently elongated and inclined orbits, collisions inevitably occurred, and this led to the fact that their movements were averaged, approached circular and lying in planes close to each other. From this, a gas-dust disk arose from a cloud around the Sun, becoming thinner, but denser. This dense layer of particles in parts close to the Sun absorbed its heat. Therefore, it was very cold inside the disk farther from the sun, and the gases there froze on dust particles. This explains why planets far from the Sun are richer in gas than those close to it. This idea, as well as the theory of cloud evolution, was developed by L.E. Gurevich and A.I. Lebedinsky, and O.Yu. Schmidt found that their picture of cloud evolution is more probable than the one that he himself had drawn before. The developed mathematical picture of cloud evolution, although containing a number of additional hypotheses, can be called a theory that lies within the framework of the Schmidt hypothesis. Schmidt's main hypothesis is the assumption that the planets arose from a cold cloud of particles, and the main role in it was played by the behavior of solid dust particles and the assumption that the cloud was captured by the Sun and, moreover, when the latter was already fully formed.

The further picture of the evolution of the gas-dust disk is briefly presented as follows. In the condensed cloud, dust clusters arose, in which the collisions of dust particles led to their merging into solid bodies with diameters, as in modern asteroids. Many of them collided and crushed, but the larger ones, the “embryos” of the planets, survived and sucked in the surrounding fragments and dust residues, first attaching them during collisions, and then more and more due to their attraction. At the same time, the dense embryos of the planets were surrounded by swarms of bodies and their fragments, circulating around them and giving birth to the satellites of the planets in the same way that these planets themselves arose.

From the lenticular form of the nebula surrounding the Sun, and from the predominance of motions in it that are parallel to each other and directed in the same direction, the main characteristic features of the structure of the solar system immediately follow: the rotation of all the planets around the Sun in the same direction, small angles between the planes of their orbits, as well as the almost circular shape of their orbits.

The rotation of the planets around their axis, which none of the previous theories could explain, Schmidt's theory explains as follows. Under the influence of the fall of meteorites on the planet, it must come into rotation, and, moreover, in exactly the same direction in which it rotates around the sun. If by chance in the region where the planet was formed, meteorites with orbits slightly elongated and slightly inclined to the average plane of the solar system were not sufficiently predominant, the planet could rotate in the opposite direction, which explains the well-known case of this kind - the rotation of Uranus .

Here I have given an idea of ​​only one - the most developed - of the many cosmogonic hypotheses. There is no single view on the process of the formation of planets and satellites yet.

ORIGIN OF LIFE

The problem of life in space is one of the most fascinating and popular problems in the science of the Universe, which has long been of concern not only to scientists, but to all people. Even J. Bruno and M. Lomonosov suggested a plurality of inhabited worlds. The study of life in the universe is one of the most difficult tasks that mankind has ever faced.

All data about life outside the Earth are purely hypothetical. Therefore, the scientific discipline - "exobiology" is engaged in deep research of biological patterns and cosmic phenomena.

So the study of extraterrestrial, cosmic life forms would help a person, firstly, to understand the essence of life, i.e. what distinguishes all living organisms from inorganic nature, secondly, to find out the ways of the emergence and development of life and, thirdly, to determine the place and role of man in the universe. Now it can be considered fairly firmly established that on our own planet life arose in the distant past from inanimate, inorganic matter under certain external conditions. Of these conditions, three main ones can be distinguished. First of all, it is the presence of water, which is part of the living substance, the living cell. Secondly, the presence of a gaseous atmosphere necessary for the gas exchange of the body with external environment. True, one can imagine any other environment. The third condition is the presence on the surface of a given celestial body of a suitable temperature range. External energy is also needed for the synthesis of a molecule of living matter from the original organic molecules: the energy of cosmic rays or ultraviolet radiation or the energy of electronic discharges. External energy is also needed for the subsequent life of living organisms. The conditions necessary for the emergence of life, at one time, developed naturally, in the course of the evolution of the Earth. There is no reason to believe that they cannot be formed in the process of development of other celestial bodies.

Many hypotheses have been put forward in this regard. Academician A.I. Oparin believes that life should have appeared when the surface of our planet was a continuous ocean. As a result of the combination of C 2 CH 2 and N 2, the simplest organic compounds arose. Then, in the waters of the primary ocean, the molecules of these compounds united and strengthened, forming a complex solution of organic substances, at the third stage, complexes of molecules separated from this environment, which gave rise to primary living organisms. Oro and Fesenkov noticed that comets and meteorites can be a kind of carriers, if not of life itself, then at least of its initial elements. However, if we do not enter into an area close to fantasy, and remain on the basis of only fairly firmly established scientific facts, then when looking for living organisms on other celestial bodies, we must first of all proceed from what we know about earthly life.

Search for extraterrestrial civilizations

The appearance of life outside the Earth at any level of its development is in itself a remarkable phenomenon. But the search for life is also conducted at a higher level of the mind, in other ways. Reason is associated with the concept of civilization. Now the presence of extraterrestrial civilizations (EC) is not excluded, which causes hope and desire of scientists in establishing contact with them.

One of the ways to search for an EC is radio astronomy, which consists in sending radio signals from the Earth to certain parts of the Universe. The signals contain information about earthlings and our civilization, questions about the nature of another civilization, and a proposal to establish mutual contact.

The second method was demonstrated during the launch of automatic interplanetary stations for the study of the outer planets of the solar system, the Pioneers and Voyagers, which, when they were supposed to meet with the CC (flying past the outer planets and ending up in interstellar space), would carry detailed information about our civilization, friendly wishes aliens, that is, it was assumed that in case of a possible meeting of terrestrial vehicles, the CC would be able to decipher the message of earthlings, and, perhaps, would like to make contact with us.

PHILOSOPHICAL AND WORLD VIEW PROBLEMS OF COSMOLOGICAL EVOLUTION

The emergence and development of modern relativistic cosmology is of great ideological significance. It has largely changed our previous ideas about the scientific picture of the world. Especially radical was the discovery of the so-called redshift, indicating the expansion of the universe. This fact could not be ignored when constructing cosmological models. Whether to consider the Universe as infinite or finite depends on specific empirical studies and, above all, on the determination of the density of matter in the Universe. However, the estimation of the distribution density of matter in the Universe encounters serious difficulties associated with the presence of the so-called hidden (invisible) matter in the form of dark clouds of cosmic matter. Although no definitive conclusion about whether the universe is finite or infinite is yet to be made, much evidence seems to favor an infinite model. In any case, such a model agrees better with an infinitely expanding universe. The closed model assumes the end of such expansion and the assumption of its subsequent contraction. The fundamental drawback of such a model is that modern science does not have any facts confirming such compression. In addition, supporters of a closed universe recognize that the evolution of the universe began with a "big bang". Finally, the problem of estimating the distribution density of matter and the magnitude of the space-time curvature associated with it remains unresolved.

An important problem is also the estimation of the age of the Universe, which is determined by the duration of its expansion. If the expansion of the Universe proceeded at a constant speed equal to 75 km/s at the present time, then the time elapsed since the beginning of the "big bang" would be 13 billion years. However, there are reasons to believe that its expansion is slowing down. Then the age of the universe will be less. On the other hand, if we assume the existence of repulsive cosmological forces, then the age of the Universe will be greater.

Significant difficulties are also associated with the substantiation of the initially "hot" model in the singular region, since the assumed densities and temperatures have never been observed or analyzed in modern astrophysics. But the development of science continues, and there is reason to hope that these most difficult problems will eventually be resolved.

CONCLUSION

We know the structure of the universe in a vast volume of space, which light takes billions of years to cross. But the inquisitive thought of man strives to penetrate further. What lies beyond the observable region of the world? Is the universe infinite in volume? And its expansion - why did it start and will it always continue in the future? And what is the origin of the "hidden" mass? And finally, how did intelligent life originate in the universe?

Does it exist anywhere else besides our planet? There are no definitive and complete answers to these questions yet.

The universe is inexhaustible. The thirst for knowledge is also tireless, forcing people to ask more and more new questions about the world and persistently seek answers to them.

LIST OF USED LITERATURE

Vorontsov-Velyaminov B.A. "Essays on the Universe", M .: "Science" 1976.

Dagaev M.M., Charugin V.M. Book for reading on astronomy. M .: "Enlightenment", 1988.

Kazyutinsky V.V. "Universe Astronomy, Philosophy", M .: "Knowledge" 1972.

Mizgun Yu. G. Extraterrestrial civilizations. M.: Ecology and health, 1993.

Novikov I.D. Evolution of the Universe. M.: "Nauka", 1990.

Popov S.B. Relic radiation. Article on the Star Fox server, http://www.starfox.telecom.nov.ru/.

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For two centuries now, the problem of the origin of the solar system has been worrying the outstanding thinkers of our planet. This problem was dealt with, starting from the philosopher Kant and the mathematician Laplace, a galaxy of astronomers and physicists of the 19th and 20th centuries.

The rocket is the only vehicle capable of deriving spacecraft into the space. And then K. Tsiolkovsky can be recognized as the author of the first space rocket, although the origins of the appearance of rockets belong to the distant past. From there we will begin to consider our question.

The history of the invention of the rocket

Most historians believe that the invention of the rocket dates back to the Chinese Han Dynasty (206 BC-220 AD), the discovery of gunpowder and the beginning of its use for fireworks and entertainment. When a powder shell exploded, a force arose that could move various objects. Later, according to this principle, the first cannons and muskets were created. Gunpowder weapon shells could fly long distances, but they were not rockets, since they did not have their own fuel reserves, but it was the invention of gunpowder that became the main prerequisite for the emergence of real rockets. The description of the flying "fire arrows" used by the Chinese shows that these arrows were missiles. A tube of compacted paper was attached to them, open only at the rear end and filled with a combustible composition. This charge was set on fire, and then the arrow was fired with the help of a bow. Such arrows were used in a number of cases during the siege of fortifications, against ships, cavalry.

In the XIII century, together with the Mongol conquerors, rockets came to Europe. It is known that rockets were used by the Zaporozhye Cossacks in the 16th-17th centuries. In the 17th century, a Lithuanian military engineer Kazimir Semenovich described a multi-stage rocket.

At the end of the 18th century in India, rocket weapons were used in battles with British troops.

IN early XIX century, the army also adopted combat missiles, the production of which was established William Congreve (Congreve's Rocket). At the same time, a Russian officer Alexander Zasyadko developed the theory of rockets. Great success in improving missiles was achieved in the middle of the century before last by the Russian general of artillery Konstantin Konstantinov. Attempts to mathematically explain jet propulsion and create more effective missile weapons were made in Russia Nikolai Tikhomirov in 1894.

theory jet propulsion created Konstantin Tsiolkovsky. He put forward the idea of ​​using rockets for space flights and argued that the most efficient fuel for them it would be a combination of liquid oxygen and hydrogen. He designed a rocket for interplanetary communication in 1903.

German scientist Hermann Oberth in the 1920s he also laid out the principles of interplanetary flight. In addition, he conducted bench tests of rocket engines.

American scientist Robert Goddard in 1926 he launched the first liquid-propellant rocket, fueled by gasoline and liquid oxygen.

The first domestic rocket was called GIRD-90 (an abbreviation for "Jet Propulsion Study Group"). It began to be built in 1931, and was tested on August 17, 1933. GIRD at that time was headed by S.P. Korolev. The rocket took off at 400 meters and was in flight for 18 seconds. The weight of the rocket at the start was 18 kilograms.

In 1933, in the USSR, the Reactive Institute completed the creation of a fundamentally new weapon - rockets, the installation for launching which later received the nickname "Katyusha".

At the rocket center in Peenemünde (Germany), a A-4 ballistic missile with a range of 320 km. During World War II, on October 3, 1942, the first successful launch of this missile took place, and in 1944 its combat use under the name V-2 began.

The military application of the V-2 showed the tremendous potential of rocket technology, and the most powerful post-war powers - the United States and the USSR - also began to develop ballistic missiles.

In 1957 in the USSR under the leadership Sergei Korolev as a means of delivery nuclear weapons The world's first intercontinental ballistic missile R-7 was created, which in the same year was used to launch the world's first artificial Earth satellite. Thus began the use of rockets for space flights.

Project by N. Kibalchich

In this regard, it is impossible not to recall Nikolai Kibalchich, a Russian revolutionary, a member of the People's Will, and an inventor. He was a participant in the assassination attempts on Alexander II, it was he who invented and manufactured throwing shells with “explosive jelly”, which were used by I.I. Grinevitsky and N.I. Rysakov during the assassination attempt on the Catherine Canal. Sentenced to death.

Hanged with A.I. Zhelyabov, S.L. Perovskaya and other Pervomartovtsy. Kibalchich put forward the idea of ​​a missile aircraft with an oscillating combustion chamber for thrust vector control. A few days before the execution, Kibalchich developed an original design for an aircraft capable of making space flights. The project described a gunpowder device rocket engine, flight control by changing the angle of inclination of the engine, program combustion mode and much more. His request to transfer the manuscript to the Academy of Sciences was not granted by the commission of inquiry, the project was first published only in 1918.

Modern rocket engines

Most modern rockets are equipped with chemical rocket engines. Such an engine can use solid, liquid or hybrid propellants. The chemical reaction between the fuel and the oxidizer begins in the combustion chamber, the resulting hot gases form an effluent jet, are accelerated in the jet nozzle (or nozzles) and expelled from the rocket. The acceleration of these gases in the engine creates thrust, a pushing force that makes the rocket move. The principle of jet propulsion is described by Newton's third law.

But not always chemical reactions are used to propel rockets. There are steam rockets, in which superheated water flowing out through a nozzle turns into a high-speed steam jet that serves as a propeller. The efficiency of steam rockets is relatively low, but this is compensated by their simplicity and safety, as well as the cheapness and availability of water. The operation of a small steam rocket was tested in space in 2004 aboard the UK-DMC satellite. There are projects for the use of steam rockets for interplanetary transportation of goods, with water heating due to nuclear or solar energy.

Rockets like steam, in which the heating of the working fluid occurs outside the working area of ​​the engine, are sometimes described as systems with external combustion engines. Most designs of nuclear rocket engines can serve as examples of external combustion rocket engines.

Currently being developed alternative ways lift spacecraft into orbit. Among them are the "space elevator", electromagnetic and conventional guns, but so far they are at the design stage.

"DIVO" Russian book of records and achievements

HUMAN ACTIVITIES: Space exploration: spacecraft

SPACE VEHICLES

INVENTED THE ROCKET

The author of the first in Russia project of a rocket apparatus for human flight was the Russian inventor Nikolai Ivanovich Kibalchich (1853 - 1881). In 1871 he entered the St. Petersburg Institute of Railway Engineers. Narodovolets Kibalchich was imprisoned for an attempt on the life of Tsar Alexander II. In conclusion, in 1881, Kibalchich developed an original design for a manned jet aircraft. The project described the device of a powder rocket engine, flight control by changing the angle of inclination of the engine, a programmed combustion mode, and much more. On April 3, 1881, Nikolai Kibalchich was hanged in St. Petersburg "according to the highest decree."

FIRST ROCKET

The first domestic rocket was called GIRD-90 (an abbreviation for "Jet Propulsion Study Group"). It began to be built in 1931, and was tested on August 17, 1933. The GIRD at that time was headed by S.P. Korolev (1906/07 - 1966). The rocket took off at 400 meters and was in flight for 18 seconds. The weight of the rocket at the start was 18 kilograms.

FIRST SATELLITE

On the night of October 4, 1957, the first artificial Earth satellite (AES) was launched from Baikonur, Northern Tyuratam (275 kilometers east of Lake Aral). Its orbit at perigee is 228 kilometers, at apogee - 947 kilometers, and the period of revolution was 96.17 minutes. The satellite was spherical (58 centimeters in diameter) and weighed 83.6 kilograms. It lasted 92 days, making about 1400 revolutions around the Earth. AES burned down on January 4, 1958. The Sputnik launch vehicle, 29.167 meters long, was designed under the leadership of Sergei Pavlovich Korolev.

"LUNOKHOD-1"

Lunokhod-1 is the first automatic self-propelled vehicle. It was delivered to the Moon on November 17, 1970 in the region of the Sea of ​​Rains. "Lunokhod-1" weighed 756 kilograms. He explored the surface of the Moon on an area of ​​80,000 square meters and obtained more than 200 panoramas. In 301 days, 6 hours and 37 minutes, Lunokhod-1 covered a distance of 10.54 kilometers.

ARTIFICIAL SATELLITE OF THE SUN

For the first time in the world, the second space velocity was achieved during the flight of the Soviet spacecraft Luna-1. It was launched on January 2, 1959 and became the first artificial satellite of the Sun.

FIRST ORBITAL STATION

The first orbital station "Salyut", designed for long-term flights in orbit around the Earth, was launched on April 19, 1971. The mass of the fully charged station was 18.9 tons, the length was 16 meters, the transverse dimension with the solar panels open was 16.5 meters. The station was put into orbit without a crew using a powerful Proton launch vehicle, although it could fly in automatic mode and with the crew on board.

FIRST MARS

For the first time in the world, a spacecraft was launched to the planet Mars on November 1, 1962. It was the Soviet "Mars-1". The approach to the planet occurred on June 19, 1963 at a distance of 197 thousand kilometers.

"BURAN" - DOMESTIC SPACE "SHUTCH"

On November 15, 1988, the first 205-minute Buran space flight was completed. The first domestic space "shuttle" made its first flight without a crew - in automatic mode, controlled from the Earth. The reentry Buran spacecraft was delivered into orbit using the Energia rocket, capable of launching a payload with a mass of more than 100 tons into orbit. The power developed by its starting engines reaches 170 million horsepower. This is almost 3 times more than that of the most powerful American Saturn-5 rocket.

Each of us has heard more than once that space is something outside our planet, it is the Universe. In general, space is a space that stretches endlessly in all directions, including galaxies and stars, and planets, cosmic dust and other objects. There is an opinion that there are other planets or even entire galaxies that are also inhabited by intelligent people.

A bit of history

The middle of the 20th century was remembered by many as the space race, the winner of which was the USSR. In 1957, an artificial satellite was created and launched for the first time, and a little later, the first living creature visited space.

Two years later, an artificial satellite of the Sun entered orbit, and a station called Luna-2 was able to land on the surface of the Moon. The legendary Belka and Strelka went into space only in 1960, and a year later a man also went there.

The year 1962 was remembered for the group flight of ships, and 1963 for the fact that for the first time a woman was in orbit. Man managed to reach open space two years later.

Each of the subsequent years of our history was marked by events related to

The station of international importance was organized in space only in 1998. It was the launch of satellites, and the organization and numerous flights of people from other countries.

What does it represent

The scientific point of view says that space is certain parts of the universe that surround themselves and their atmospheres. However, it cannot be called completely empty. It has been shown to contain some hydrogen and has interstellar matter. Scientists have also confirmed the existence of electromagnetic radiation within it.

Now science does not know the data on the final limits of the cosmos. Astrophysicists and radio astronomers claim that instruments cannot "see" the entire cosmos. This is despite their workspace spanning 15 billion

Scientific hypotheses do not deny the possible existence of universes like ours, but there is no confirmation of this either. In general, space is the universe, it is the world. It is characterized by orderliness and materialization.

Learning process

Animals were the first in space. People were afraid, but wanted to explore the unknown spaces, so dogs, pigs and monkeys were used as pioneers. Some of them returned, some did not.

Now people are actively exploring outer space. It has been proven that weightlessness adversely affects human health. It does not allow fluids to move in the right directions, which contributes to the loss of calcium in the body. Also in space, people become somewhat chubby, there are problems with the intestines and clogging of the nose.

In outer space, almost every person gets "space sickness". Its main symptoms are nausea, dizziness, and headache. Hearing problems are the result of this disease.

Space is the space in whose orbits you can observe the sunrise about 16 times a day. This, in turn, negatively affects the biorhythms, prevents normal falling asleep.

It is interesting that the development of a toilet bowl in space is a whole science. Before this action begins to be perfect, all astronauts practice on a mock-up. Technique is worked out over a certain period of time. Scientists tried to organize a mini-toilet directly in the spacesuit, but this did not work out. Instead, ordinary diapers began to be used.

Every astronaut, after returning home, wonders for some time why objects fall down.

Not many people know why the first food in space was presented in tubes or briquettes. In fact, swallowing food in outer space is quite a challenge. Therefore, food was pre-dehydrated to make this process more accessible.

Interestingly, people who snore do not experience this process in space. It is still difficult to give an exact explanation for this fact.

death in space

Women who have artificially enlarged their breasts will never be able to know the cosmic expanses. The explanation for this is simple - implants can explode. The same fate, unfortunately, can befall the lungs of any person if he finds himself in space without a spacesuit. This will happen due to decompression. The mucous membranes of the mouth, nose and eyes will simply boil.

Space in ancient philosophy

Space is in philosophy a kind of structural concept that is used to designate the world as a whole. Heraclitus used the definition as a “world-building” more than 500 years ago BC. This was supported by the pre-Socratics - Parmenides, Democritus, Anaxagoras and Empedocles.

Plato and Aristotle tried to show the cosmos as an extremely complete being, an innocent being, an aesthetic whole. The perception of outer space was based largely on the mythology of the ancient Greeks.

In his work "On Heaven" Aristotle tries to compare these two concepts, to identify similarities and differences. In Plato's Timaeus, there is a fine line between the cosmos itself and its founder. The philosopher argued that the cosmos arose sequentially from matter and ideas, and the creator put his soul into it, divided it into elements.

The result was the cosmos as a living being with a mind. It is one and beautiful, includes the soul and body of the world.

Space in the philosophy of the 19th-20th centuries

The modern industrial revolution has completely distorted previous versions of the perception of outer space. A new "mythology" was taken as a basis.

At the turn of the century, such a philosophical trend as cubism arose. He largely embodied the laws, formulas, logical constructions and idealizations of Greek Orthodox ideas, which, in turn, borrowed them from ancient philosophers. Cubism is a good attempt by a person to know himself, the world, his place in the world, his vocation, to determine the basic values.

He did not go far from ancient ideas, but changed their root. Now the cosmos is in philosophy something with design features that were based on the principles of Orthodox personalism. Something historical and evolutionary. Outer space can change for the better. Biblical traditions were taken as a basis.

The cosmos, in the view of the philosophers of the 19-20s, combines art and religion, physics and metaphysics, knowledge about the world around us and human nature.

conclusions

It can be logically concluded that the cosmos is the space that is a single whole. Philosophical and scientific ideas about it are of the same nature, with the exception of ancient times. The topic "space" has always been in demand and enjoyed a healthy curiosity among people.

Now the universe is fraught with many more mysteries and mysteries that you and I have yet to unravel. Each person who finds himself in space discovers something new and unusual for himself and for all mankind, acquaints everyone with his feelings.

Outer space is a collection of various matters or objects. Some of them are closely studied by scientists, and the nature of others is generally incomprehensible.