1. Exploration of the moon in antiquity
2. Physical conditions on the moon

B. Change of lunar phases

1. moon relief

B. Creation of craters. Meteorites.

B. Flight spaceships, exploring the moon.

D. Lunar rocks.

1. Another side of the moon
2. moon magnetism.
3. man on the moon

MOON SONNET

Moon and lotus ... All verses of the East
You have been sung. Glorified the East
A radiant disk shining high,
Love and glory sweet flower.

Moon and lotus... exudes lotus

Soy gentle scent over the silence of the waters,

And the moonlight still pours quietly ...

But there is a rover on the moon today.

The moon was rediscovered by them,

And, having established a connection, he informed us,
That he found a piece of a meteorite,
That the flesh of the moon is basalt and diabase ...

Still the ancient moonlight pours,
But I am writing a sonnet in a new way.

Lodongiin Tudev

"ANCIENT" MOON

The moon is a natural satellite of the Earth and the closest celestial body to the Earth, and therefore it is best studied, but several millennia ago, with what amazement, primitive man followed the lunar disk! A pensive and mysterious luminary, a dim night sun, a ball wandering alone in the silent firmament of heaven - the Moon at all times and among all peoples in particular attracted human gazes and thoughts. The moon was subject to the vicissitudes of human opinion. Jules Verne, Cyrano de Bergerac and other writers, dreamers imagined, and some even claimed, that the Moon is inhabited by living beings and rich in fruitful life. Before the invention of the telescope, philosophers, quite naturally, were inclined to see the earth in the moon, similar to the one on which we live. When Galileo, pointing his first telescope at this sphere, found mountains and valleys there, similar to the various forms of relief of the surface of our planet, and vast gray plains that could easily be mistaken for seas, the similarity between these worlds and ours seemed obvious, and it was immediately inhabited not only by human beings, but also by various animals. The first maps were drawn, and it was agreed that the large dark spots be christened with the name of the "sea", which they still bear.

Astronomers, thinkers, were sure that rapid successes would follow the increase in telescopes, and in the reign of Louis XIV it was even supposed to build a "tube 100 thousand feet long for viewing animals existing on the Moon." But no matter how hard the opticians tried, their successes could not go far on a par with the imagination. When they began to clearly distinguish the surface of the lunar seas, it turned out that it was not liquid and not smooth, but sandy and uneven. Not a single real morph, not a single lake, not the slightest trace of the presence of water in any form, in the form of clouds, snow or ice, has been discovered on this luminary. No less careful observation of the stars and planets at the moment they are covered by the Moon passing before us showed, moreover, that the light of these luminaries, when they come into contact with the lunar edge, is not at all weakened or refracted, and that this ball is not surrounded by any noticeable atmosphere. The gradual lunar life dissipated like smoke, and little by little it became a habit to put in astronomical books the phrase: "The moon is a lifeless luminary." Today this has been proven both theoretically and practically. The moon is devoid of atmosphere and water, which cannot exist in liquid form without a dense atmosphere. Without an atmosphere, the existence of any organic life is impossible.

PHYSICAL CONDITIONS ON THE MOON

As already mentioned: the Moon is the closest celestial body to the earth, and therefore the best studied. The closest planets to us are about 100 times further away. The moon is four times smaller than the Earth, its radius is 1738 km, or 0.272 of the Earth's radius. Its mass is 81 times less than the Earth and is equal to 0.0123 Earth masses. The mass of the Moon is reliably determined from the motion of its artificial satellites, which are repeatedly launched into selenocentric orbits, i.e. orbits around the moon (from the Greek. "Selena" - the moon). Its average density is 3.55 * 10 3 kg / m 3 or 0.6 of the density of the Earth, and the acceleration free fall on its surface g=1.63 m/s 2 , i.e. 6 times less than the earth, so that any object on the lunar surface weighs one times less than on Earth. As already noted, there is no atmosphere on the Moon that softens the scorching solar radiation and protects against cosmic rays and meteor showers. There are no clouds, no water, no fogs, no rainbows, no dawns with dawn. Due to the absence of air and a gaseous shell, very curious phenomena occur on the moon. There is no twilight here, night is replaced by day and day is replaced by night instantly, like a lamp that instantly goes out and lights up in the dark. There is no gradual transition from warm to cold. The temperature on the moon immediately drops from the boiling point to the temperature of interplanetary space. The huge temperature differences on the lunar surface from day to night are explained not only by the absence of an atmosphere, but also by the duration lunar day and the moonlit night, which corresponds to our two weeks. The temperature at the subsolar point of the Moon is +120С, and at the opposite point of the night hemisphere -170С. this is how the temperature changes during one lunar day! For the same reason, meteorites without braking hit the lunar surface with great speed, causing strong shaking of the soil and forming funnels.

Due to the absence of an atmosphere, there are no colors in the lunar sky. Throughout the night, which lasts two Earth weeks, and an equally long day with the scorching Sun over the Moon, the black sky is dotted with many stars that stand out clearly and completely non-flickering. The stars in the lunar sky are visible during the day as well as at night.

Several millennia ago, people watched in amazement as the moon grew and waned, like a living being, grew fat and dried up. Disappeared completely and steadily reborn again in the starry blackness of the sky. There was a steady pattern in this astonishing change, which manifested itself from the beginning of the century, which will remain unchanged until the end of time. And when people finally realized that there were four quarters between the two new moons, they took the most important step from a short measure of the time of the day to a longer one - a month. The periodic change of the lunar phases into the flesh and blood of human ideas about the world. It is no coincidence that the Moon in Sanskrit is called "mas", i.e. measuring instrument, it is no coincidence that the Latin "mecules" - month - is in close connection with the word "mekuura" - measure. It was the Moon, not the Sun, that became the first object of worship. The peoples of Central America have long had a lunar year - a measure of time designed to establish religious holidays. The lunar calendar was also used by the peoples inhabiting Mesopotamia. When determining church holidays, the lunar calendar is guided by Jews, Christians, who determine the onset of Easter according to it. The coincidence of the phases of the moon with the most different manifestations animate and inanimate nature: ebb and flow in the seas, a decrease in temperature and abundant dews that usually fall on a clear moonlit night, an increase in the growth of some plants and a lunar periodicity of vital functions human body- all this has long worried people. Subsequently, the phases of the moon were associated with the concept of death and resurrection. With the stay of the month in the new moon, not only the growth of cereals is associated, but also the well-being of the herds and the health of children. So among the Central African tribe, when a new month appeared, mothers carried out their babies and showed their rebirth to the moon. When the Moon entered the last quarter, its influence, on the contrary, was considered unfavorable. It was better not to start new cases. On everything the globe farmers have a belief that it is necessary to sow when it is at a loss. At a certain period, the cult of the Moon occupied a central place in many religions. Now science, medicine point to the possible connection of some disorders of the human psyche with the phases of the moon. The moon can affect the human body, which is more than 80% water, just as it affects the seas and oceans.

The huge luminary of the lunar sky, the Earth, represents the same phases for the Moon as the Moon does for us, but in reverse order. During the new moon, the Sun illuminates the hemisphere of the Earth facing our satellite, and then there is a “full Earth”. During the full moon, on the contrary, the unlit hemisphere is turned towards our satellite, and then it happens " new earth". When the moon shows us the first quarter, the earth represents the last, and so on. Regardless of these phases, our ball appears to the Moon as rotating around its axis for 24 hours and 48 minutes, because. The moon returns to each earth meridian not earlier than after this period of time. Recall that the period of rotation of the Moon around its axis is 27.32 g (Earth days) and therefore it faces the earth with one hemisphere. Full moons are repeated after 29.53 g, which means that a solar day on the Moon lasts 29.53 g, i.e. about 14.8 g lasts a day and the same amount a night.

RELIEF OF THE MOON

Since the time of Galileo, the mapping of the moon began. First detailed maps of the lunar surface was compiled by the outstanding Polish astronomer J. Hevelius (1611-1687) and published in 1647 in the essay "Selenography" or "Description of the Moon". In 1651, the Italian astronomer J. Riccioli (1598-1671) also published a map of the Moon, compiled by him together with the Italian physicist F. Grimaldi. (1618-1663). It was on this map that the rounded lowlands were named for the first time by seas that have retained their names to this day: the Sea of ​​Tranquility, the Sea of ​​Clarity, the Sea of ​​Danger, the Sea of ​​Rains, the Sea of ​​Clouds, etc. Their sizes are from 200 to 1100 km across. "Sea" - lowlands in which there is not a drop of water. Their bottom is dark and relatively flat. The surface of the seas is complex and covered with dark matter, including hardened lava, once erupted from the lunar interior. The largest lowland, 2000 km long, is called the Ocean of Storms. The surface of the seas has folds and hills, as well as small pointed and rounded hills, which are the tops of low mountains, filled with subsequently hardened lava. The marginal zones of the seas, characteristic in their outlines, are called bays, and small isolated dark lowlands are called lakes. Seas and lakes occupy about 40% of the entire surface of the Moon visible from Earth, and the vast majority of them are located in its northern hemisphere. The rest (60%) of the lunar hemisphere is a mainland covered with both individual mountains and mountain ranges and ranges. Most of the mountain ranges stretch along the margins of the seas and bear earthly names proposed by J. Hevelius. So, the Sea of ​​​​Rains is bounded from the northeast by the Alps, from the east by the Caucasus, from the southeast by the Apennines, and from the south by the Carpathians. Some mountain ranges are named after scientists: the mountains of D'Alembert, the mountains of Leibniz, etc. The height of the mountains is different, individual mountain peaks - peaks - rise up to 9 km. The mountain slopes are cut by numerous gorges and cracks, and long valleys stretch between the mountains. The shape of the lunar mountains is mostly a round mountain with a hollow in the middle. But the basin is not always empty, it does not always turn out to be a newest crater: sometimes a whole mountain rises in its middle, and again with a depression, which turns out to be a newer crater, but rarely, rarely active with reddening inside, at its very bottom, lava. There are many on the moon and plateaus with steep slopes, wide and narrow cracks in the crust with a length of several tens and even hundreds of kilometers. It is better to study the lunar relief when it is obliquely illuminated by the sun's rays, especially not far from the terminator, which separates the daytime hemisphere of the Moon from the nighttime, i.e. near it, the shadows even from low mountains are very long and easily visible. It is very interesting to follow through a telescope for an hour how bright points light up near the terminator on the night side - these are the tops of the shafts of lunar craters. Gradually, a bright horseshoe emerges from the darkness - part of the crater shaft, but the bottom of the crater is still immersed in complete darkness, and finally the entire crater is outlined. It is clearly seen that the smaller the craters, the more of them. They are often arranged in chains and even "sit" on top of each other. Later craters, as already mentioned, were formed on the baths of older craters. A hill is visible in the center of the craters, in reality it is a group of mountains. The crater walls break off in terraces steeply inwards. The bottom of the craters lies below the surrounding area. The mountainous regions of the lunar surface are almost completely covered with many craters, and in a smaller number they are found in the seas. The sizes of craters are from 1 m to 250 km. Large and medium-sized craters, known since the time of the first telescopic observations of the moon, are named after scientists: Aristotle, Copernicus, Tycho, Herodotus, Timocharis, Hipparchus, Kepler, and others.

In the Sea of ​​Rains, large craters Archimedes (d=73 km), Aristotle (d=51 km), Autolycus (d=36 km) are clearly distinguished, and in mountainous regions, in the middle of the lunar disks, there are whole chains of large craters, including Ptolemy (d=146 km), Alfons (d=124 km) and Arzakhel (d=32 km). Many large and medium-sized craters are surrounded by gently sloping ridges (ring mountains) and have a flat bottom. Others are in the form of funnels, which are formed during explosions. Small craters generally cover the entire lunar surface and even the bottom and ridges of larger craters. Many small craters (up to 10-15 km in diameter) were formed by explosions of material bodies colliding with the Moon. Larger craters, especially those with central hills, are of volcanic origin, which is confirmed by a photograph of the crater Copernicus, obtained from a height of 25 km by one of the artificial satellites of the moon, the bottom of which bears clear signs of volcanism. Let us consider in more detail the origin of craters.

Most of the craters owe their origin to the impacts of small meteorites. When a meteorite hits the moon, it does not encounter opposition from the atmosphere. Without changing speed, it hits the ground and explodes. If the impact speed is 16 km/s, then the average speed during penetration into the ground is 8 km/s. Even a one and a half kilometer asteroid will slow down in less than half a second. Naturally, an explosion of extraordinary force occurs and a crater appears. The crater is formed partly under the influence of gas that arose during the evaporation of a meteorite and ground rocks, and partly under the influence of a shock wave formed in the ground. A shock wave occurs when suddenly released energy propagates through a medium at supersonic speeds. The resulting forces eject part of the soil located above the point of explosion far from the point of impact, but mainly the crater is formed by the instantaneous displacement of rocks in all directions from the point of explosion. The energy is so great that it far exceeds the energy chemical bonds in the rocks and when the shock wave propagates in them, the rocks become plastic. They are crushed, bent and squeezed up and to the sides, forming depressions and into a large part of the shaft. For example, the Sea of ​​Rains was formed in this way.

In May 1972, a large meteorite body collided with the Moon. According to the seismologist G. Latham (USA Lamont Geological Observatory), the fall was registered and transmitted by telemetry to the Earth by four seismometers delivered to the Moon by astronauts. The energy released during the fall is very high: it is equivalent to an explosion of approximately 1 thousand tons of trinitrotoluene. The crater formed during the fall is equal in area to a football field. The meteorite impact site is located in the Fra Mauro crater area, inside the Apollo 14 landing site. A shower of clouds formed by ejected rocks. It went on for about a minute. So there was a fall of a giant meteorite on the moon.

Meteorites, apparently, owe their origin to long bright rays, which radically diverge from some large craters (for example, from the craters Tycho, Copernicus, Kepler) under consideration for several hundred and even thousands of kilometers. They are chains of small craters covered with fine-grained matter. Strongly scatter sunlight.

On February 3, 1966, for the first time in the history of mankind, the automatic station Luna-9 gently descended onto the lunar surface in the Ocean of Storms. Launched from the ground on January 31, 1996. This station on February 4 and 5 transmitted to Earth an image of the lunar landscape. The soft landing of the automatic station "Luna-9" on the surface of the Moon is an outstanding scientific and technical achievement. For the first time, it became possible to study the microstructure of the lunar surface. Near the station, there is no noticeable layer of dust inside a small crater. The ground is hard enough to support the weight of the station. On the surface, individual stones not only are not covered by dust, but, as it were, "grow" from the surface of the soil as a result of its gradual destruction. The landing site is a fairly flat surface with a well-defined relief, with hills, noticeable lines along the entire line of the visible horizon. Most characteristic form mesorelief are holes and craters, i.e. lowering - pits of very different sizes. Another common landscape element is rocky and lumpy objects. Their sizes are different. On June 21, 1969, the landing cabin "Eagle" ("Eagle") of the American spacecraft "Apollo II" landed on the moon in the Sea of ​​Tranquility for the first time and the first people stepped on the lunar surface; they were N. Armstrong and E. Aldrin. They installed several scientific instruments on the Moon, including seismographs, took samples of lunar rocks, returned to the ship, where astronaut M. Collins was waiting for them, and returned to Earth on July 24. In the next 2 years, 5 more American expeditions visited the Moon, returning safely to Earth. They walked and even drove a special all-terrain vehicle on the surface of the Moon, installed various devices, in particular seismographs for recording "moonquakes". Chemical analysis of samples of lunar matter showed that the rocks of the moon are not as diverse as those of the earth, and are similar in composition to basalts.

Soviet scientists study the moon with automatic devices. On September 20, 1970, the Luna-16 automatic station landed in the Sea of ​​Plenty; in subsequent years, Luna-20 and Luna-24 landed on the Moon and delivered samples of lunar soil to Earth. In general, the mineral composition of lunar rocks is similar to the composition of terrestrial basalts, but reflects the features of the chemical composition. In particular, the low fugacity of oxygen during the crystallization of lunar rocks leads to the formation of metallic iron and the virtual absence of iron oxide - a phenomenon extremely rare for the Earth. As a result, we find here such exotic minerals as troilite, pyroxferraite and armalcolite, the latter mineral named after the three astronauts of Apollo 11 - N. Armstrong, E. Aldrin and M. Collins. The average soil density is close to 1.5 g/cm 3 , the low density is due to its high porosity (up to 50%). The age of lunar rocks is estimated from 3.1 to 4.2 billion years, which allows us to consider the age of the moon close to 4.6 billion years, i.e. to the age of the earth.

They rained down on the moon and made automatic self-propelled laboratories - lunar rovers. On November 17, 1970, Luna-17 delivered Lunokhod-1, and on January 16, 1973 Luna-21 delivered Lunokhod-2. For almost 10 months, Lunokhod-1 plied the expanses of the Sea of ​​Rains, transmitted photo panoramas, performed chemical analyzes soil. This experiment significantly enriched our knowledge of the Earth's natural satellite and showed the promise of further exploration of the Moon and planets by self-propelled vehicles. Several types of craters appear on the panoramas obtained by Lunokhod-1. Selenologists arranged the craters in a row according to the degree of severity - from the most recent and clearly expressed complex ones to highly altered ones, devoid of a rampart and stones. Such a morphological series reflects the stages of evolution, the processes of destruction of the lunar surface due to micrometeorite erosion. Morphological analysis confirmed the concept of predominantly impact-explosive origin of the studied craters. The collected material on the distribution of craters and stones made it possible to determine the age and sequence of their formations.

"Lunokhod-2" landed on the surface of the Sea of ​​Clarity. Its weight was 840 kg. There are no fundamental differences between them and Lunokhod-1. But the truth is, the new machine weighs more and its equipment is more advanced. One television camera is taken out of the common housing, so that the track is better viewed when the lunar rover moves. Not a single self-propelled vehicle made such a difficult route. He several times crossed 15-meter craters with inner slopes up to 20-25. In separate sessions, the self-propelled laboratory traveled up to 2 km. The studies of Lunokhod-2 significantly supplemented and refined our understanding of the lunar relief and the processes that form it. The Lunokhod traveled several tens of kilometers on the Moon. Even in those parts of the lunar surface that look flat from Earth, the ground is replete with funnels and covered with stones of various sizes. The Lunokhod, controlled from the Earth by radio, moved "step by step" taking into account the nature of the terrain, the view of which was transmitted on television. This greatest achievement of science is important as an example of a direct study of physical conditions on another celestial body, which is located at a great distance from the Earth.

ANOTHER SIDE OF THE MOON

Despite the fact that the study of the surface of the side of the Moon visible from the Earth did not stop, throughout the history of this study, the interest of scientists in its other side, hidden from the human eye, did not weaken.

It turned out that the far side of the moon has some differences from the visible hemisphere. Photos of the far side of the moon showed that there are almost no seas on it, which occupy 40% of the area on the visible side. Several small seas occupy about 7% of the area. One of them is called the Sea of ​​Moscow, three times - the Sea of ​​Dreams, the third - the Eastern Sea, a small part of which can be traced at the very edge of the visible hemisphere. Among the numerous craters of various sizes, almost rectilinear chains of craters stretching for many hundreds of kilometers are clearly distinguished. The large crater was given the names of prominent scientists, including Russian ones - M.V. Lomonosov, K.E. Tsiolkovsky, S.P. Koroleva, I.V. Kurchatov and many others. The astronauts were not forgotten either. Two craters are named after Yu. Gagarin and V. Komarov.

At present, there are detailed maps of both hemispheres of the Moon.

The thickness of the lunar crust, apparently, does not exceed 50-60 km, below, to a depth of about 1000 km, the mantle is located, and it is difficult to judge the diameter of the core while 1500 km, but it is obvious that it is silicate and almost solid, because due to the small size and average density of the moon, the pressure in the core is not more than 6x10 4 MPa, and the temperature is above 1000С. the obtained results of direct measurements indicate that the moon cannot be hot and molten inside, but rather is a relatively cold body.

MAGNETISM OF THE MOON

Very interesting information is available on the topic: the magnetic field of the moon, its magnetism. Magnetometers installed on the moon will detect 2 types of lunar magnetic fields: constant fields generated by the "fossil" magnetism of the lunar substance, and variable fields caused by electric currents excited in the interior of the moon. These magnetic measurements gave us unique information about the history and state of the art Moon. The source of the "fossil" magnetism is unknown and indicates the existence of some extraordinary epoch in the history of the Moon. Variable fields are excited in the Moon by changes in the magnetic field associated with the "solar wind" - streams of charged particles emitted by the sun. Although the strength of the permanent fields measured on the Moon is less than 1% of the strength of the Earth's magnetic field, the lunar fields turned out to be much stronger than expected on the basis of measurements made by earlier Soviet and American devices.

The instruments delivered to the lunar surface by the Apollos testified that the constant fields on the Moon vary from point to point, but do not fit into the picture of a global dipole field similar to that of the earth. This suggests that the detected fields are caused by local sources. Moreover, the large strength of the fields indicates that the sources have become magnetized in external fields, much stronger than those present on the Moon at the present time. At some time in the past, the moon either had a strong magnetic field itself or was in a region of a strong field. We are faced here with a whole series of mysteries of lunar history: did the moon have a field similar to the earth's? Was it much closer to Earth where the Earth's magnetic field was strong enough? Did she acquire magnetization in some other area solar system and was later captured by the Earth? The answers to these questions can be encoded in the "fossil" magnetism of the lunar substance.

Variable fields generated by electric currents flowing in the bowels of the Moon are associated with the entire Moon, and not with any of its individual regions. These fields rapidly rise and fall in accordance with the changes solar wind. The properties of the induced lunar fields depend on the conductivity of the lunar fields of the interior, and the latter, in turn, is closely related to the temperature of the substance. Therefore, the magnetometer can be used as an indirect "resistance thermometer" to determine the internal temperature of the Moon.

MAN IN THE MOON

Friak Borman, the commander of the Apollo 8 spacecraft, said: “The flight became possible for us thanks to the work of thousands of people. And not only in the USA. Without the first artificial Earth satellite and the flight of Yu. Gagarin, without the research of scientists from many countries, flights to the Moon could not have taken place ... the earth is really a very small planet. outer space This is the task of all mankind, and not just individual countries.

The lunar landing day lasted a very long time, and all this time the astronauts did not have a moment of peace. They were completely absorbed in the work of the computer and therefore could not pay due attention to the orientation "according to the terrain." It wasn't until they were aiming to go below 3,000 feet that they managed to look outside for the first time. The horizon on the moon is very close, so you can't see much from that height.

The only landmark they noticed was a large and very imposing crater known as the western crater, although at this point they did not recognize it. In the last seconds of the descent, the Orel engine kicked up a significant amount of dust, which flew at a very high speed radially, almost parallel to the surface of the Moon. On Earth, dust usually floats in the air and settles very slowly. Since there is no atmosphere on the Moon, lunar dust lies in a flat and low path, leaving clear space behind it. It took the astronauts a little longer to get out of the Orel than expected. Neil Armstrong, the commander of Apollo 11, pondered what to say at that moment before stepping onto the surface of the moon. He thought about it even before the flight, but only after landing on the moon did he say: "one small step for a man is a huge leap for mankind."

Being on the lunar surface, the astronauts did not smell any smells either in spacesuits or in pressure helmets. And when they returned to the cockpit and removed their helmets, they felt some kind of smell. The smell of moon soil, acrid, like the smell of gunpowder. They brought a lot of lunar dust into the cockpit on spacesuits and shoes. The smell was felt immediately. The lunar surface at the time of landing was brightly lit. In the black sky, neither stars nor planets, with the exception of the Earth, were visible.

The lunar compartment was in a working vertical position. It was easy to keep the balance. Standing up after an accidental fall was also not difficult. In general, the feeling of attraction on the Moon is more pleasant than the earthly one, and even more pleasant than the state of weightlessness, as N. Armstrong wrote.

The sun rose above the horizon while the spacecraft was on the moon. On average, the light level turned out to be very high (as on a cloudless day on Earth). The shadows were thick, but not black. sunlight was reflected from the slopes of the lunar craters, and visibility was good.

The peculiar photometric properties of the Moon have been known for a long time. There was a fear that at a certain moment the eyes of the astronauts, blinded by the Sun, would not be able to see anything, so the trajectory of the descent of the lunar cabin was calculated so that at the landing point the sun's rays would not interfere with the astronauts. The color is barely noticeable or not detected at all. With a slight height of the Sun above the horizon, it is practically impossible to distinguish colors. When the sun rises above the horizons to 10, brown and brown hues begin to appear. And when leaving the cabin, the astronauts unexpectedly discovered that the fragments of rocks and partially lunar soil were dark gray or charcoal gray.

During the flight of Apollo 11, the earth was approximately 30 from the zenith. It seemed to be convex and very bright. 2 colors prevailed: blue - oceans and white - clouds. However, it was easy to distinguish the gray-brown color of the continents. The angular diameter of the Earth when observed and the Moon is 4 times greater than that of the Moon observed from the Earth. Although the Earth pi seemed small, it was still a very colorful sight, according to the astronauts.

It should be noted that clothing and protective equipment, equipment of astronauts has interesting features. The main details of astronauts' clothing protect the body from vacuum, thermal effects and micrometeorites. The knapsack system consists of communication equipment, ventilation and temperature and pressure control equipment. This system drops 100% oxygen. Temperature protection ensures normal operation at outdoor temperatures up to 121.

The suit is equipped with a hermetic helmet. Gloves, protective covers and various sensors.

It is put on through a vertical slit on the back and fastens. Sleeves are mounted on spherical hinges that allow rotation by hand. The hermetic helmet is a transparent bubble with a complex system. The protective shell contains 2 pairs of removable filters for UV and IR protection. The helmet has 3 bubbles that protect from the sun's rays. Multi-layer coatings provide sealing. Protection from temperature and damage from micrometeorites. The multi-layered shoes have an upper and a thick sole made of special rubber. Liquid-cooled clothing is attached directly to the body, serving as a thermal buffer between the astronaut's body and the cooling medium. In a knapsack (portable life support system) - means of communication. Sensors and device falling oxygen. Carbon dioxide is absorbed by lithium hydroxide, water by a water separator, odors by activated carbon, foreign particles by a filter, and heat by a heat sink.

The cosmonaut, dressed in a spacesuit and equipped with a knapsack. The center of gravity moves up and slightly back. To keep his balance, he leans forward. On turns, its movements are also noticeably slower than on Earth. To move faster, you need to take 3 or 4 steps with a slight acceleration or lean forward strongly and push off vigorously, gaining the desired speed from the first step. Both methods are satisfactory, but usually the astronauts used the first one. The walking speed did not exceed 0.5 m/s. At high speeds, the astronaut, taking a step, seemed to fly up. While hopping, he pushed off the surface with both feet at the same time. The latter method turned out to be the most effective when traveling long distances, because. a speed of 1-1.5 m/s was achieved, and in some areas up to 2 m/s. took a long time to choose the best way on uneven surfaces. Jumping is similar to hopping, but with them on the moon, unlike running, the legs move rather slowly. It creates a feeling of slow running. Running as we know it on Earth cannot be replicated on the Moon. You can't stop while walking. Side steps are hampered by the limited mobility of the suit. In general, movement on the Moon requires more calculation and attention than on Earth. Of course, in the conditions of lunar attraction, you want to jump up. Free jumps with movement control are possible up to 1 m. great height often end in a crash. highest height jumping was 2 m. Falls had no unpleasant consequences. Usually, in case of imbalance, a fall can be prevented by turning and stepping in the direction in which you fall. If the astronaut falls face down, he can easily get up without assistance. When falling on your back, you need to make more efforts to get up on your own. The footprint from walking deepened in the lunar soil by 1 cm, its particles stuck to the shoes. Space suit. American astronauts count. That the improvement of the suit will help to increase the efficiency of activities on the moon.

LITERATURE

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2. Tsesevich V.P. What and how to observe in the sky.
3. Parnov S., Samsonenko L. Lunarium.
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5. Siegel F.Yu. Star alphabet.
6. Sargsyan E.A. Celestial bodies are reliable landmarks.
7. Gurshtein A.A. Eternal secrets of the sky.
8. Volkov A.M. Looking for the truth.

As already mentioned: the Moon is the closest celestial body to the earth, and therefore the best studied. The closest planets to us are about 100 times further away. The moon is four times smaller than the Earth, its radius is 1738 km, or 0.272 of the Earth's radius. Its mass is 81 times less than the Earth and is equal to 0.0123 Earth masses. The mass of the Moon is reliably determined from the motion of its artificial satellites, which are repeatedly launched into selenocentric orbits, i.e. orbits around the moon (from the Greek. "Selena" - the moon). Its average density is equal to 3.55*10 3 kg/m 3 or 0.6 of the density of the Earth, and the free fall acceleration on its surface is g=1.63 m/s 2, i.e. 6 times less than the earth, so that any object on the lunar surface weighs one times less than on Earth. As already noted, there is no atmosphere on the Moon that softens the scorching solar radiation and protects against cosmic rays and meteorite streams. There are no clouds, no water, no fogs, no rainbows, no dawns with dawn. Due to the absence of air and a gaseous shell, very curious phenomena occur on the moon. There is no twilight here, night is replaced by day and day is replaced by night instantly, like a lamp that instantly goes out and lights up in the dark. There is no gradual transition from warm to cold. The temperature on the moon immediately drops from the boiling point to the temperature of interplanetary space. The huge temperature fluctuations of the lunar surface from day to night are explained not only by the absence of an atmosphere, but also by the duration of the lunar day and lunar night, which corresponds to our two weeks. The temperature at the subsolar point of the Moon is +120C, and at the opposite point of the night hemisphere -170C. this is how the temperature changes during one lunar day! For the same reason, meteorites without braking hit the lunar surface with great speed, causing strong shaking of the soil and forming funnels.

Due to the absence of an atmosphere, there are no colors in the lunar sky. Throughout the night, which lasts two Earth weeks, and an equally long day with the scorching Sun over the Moon, the black sky is dotted with many stars that stand out clearly and completely non-flickering. The stars in the lunar sky are visible during the day as well as at night.

Several millennia ago, people watched in amazement as the moon grew and waned, like a living being, grew fat and dried up. Disappeared completely and steadily reborn again in the starry blackness of the sky. There was a steady pattern in this astonishing change, which manifested itself from the beginning of the century, which will remain unchanged until the end of time. And when people finally realized that there were four quarters between the two new moons, they took the most important step from a short measure of the time of the day to a longer one - a month. The periodic change of the lunar phases into the flesh and blood of human ideas about the world. It is no coincidence that the Moon in Sanskrit is called "mas", i.e. measuring instrument, it is no coincidence that the Latin "mecules" - month - is in close connection with the word "mekuura" - measure. It was the Moon, not the Sun, that became the first object of worship. The peoples of Central America have long had a lunar year - a measure of time designed to establish religious holidays. The lunar calendar was also used by the peoples inhabiting Mesopotamia. When determining church holidays, the lunar calendar is guided by Jews, Christians, who determine the onset of Easter according to it. The coincidence of the phases of the moon with a variety of manifestations of animate and inanimate nature: ebbs and flows in the seas, a decrease in temperature and abundant dews that usually fall on a clear moonlit night, increased growth of some plants and the lunar periodicity of the vital functions of the human body - all this has long worried people. Subsequently, the phases of the moon were associated with the concept of death and resurrection. With the stay of the month in the new moon, not only the growth of cereals is associated, but also the well-being of the herds and the health of children. So among the Central African tribe, when a new month appeared, mothers carried out their babies and showed their rebirth to the moon. When the Moon entered the last quarter, its influence, on the contrary, was considered unfavorable. It was better not to start new cases. All over the globe, farmers have a belief that it is necessary to sow when it is at a loss. At a certain period, the cult of the Moon occupied a central place in many religions. Now science, medicine point to the possible connection of some disorders of the human psyche with the phases of the moon. The moon can affect the human body, which is more than 80% water, just as it affects the seas and oceans.

The huge luminary of the lunar sky, the Earth, represents the same phases for the Moon as the Moon does for us, but in reverse order. During the new moon, the Sun illuminates the hemisphere of the Earth facing our satellite, and then there is a “full Earth”. During the full moon, on the contrary, the unlit hemisphere is turned towards our satellite, and then there is a “new Earth”. When the moon shows us the first quarter, the earth represents the last, and so on. Regardless of these phases, our ball appears to the Moon as rotating around its axis for 24 hours and 48 minutes, because. The moon returns to each earth meridian not earlier than after this period of time. Recall that the period of rotation of the Moon around its axis is 27.32 g (Earth days) and therefore it faces the earth with one hemisphere. Full moons are repeated after 29.53 g, which means that a solar day on the Moon lasts 29.53 g, i.e. about 14.8 g lasts a day and the same amount a night.

Dark spots can be seen on the Moon with the naked eye. Through binoculars, and even better through a telescope, their outlines stand out more clearly. These are vast plains on the lunar surface. The first observers who looked at the Moon through a telescope mistook them for bodies of water and called them seas. But there is no water or ice on the Moon. If ever they were there, they have long since evaporated and vanished into space. This is explained by the fact that the force of gravity on the Moon is 6 times less than on Earth. The moon could not hold any significant amount of water vapor and gases around itself for a long time.

The fact that there is no noticeable atmosphere on the Moon can be seen by observing how suddenly, without any dimming, the star disappears when the Moon closes it, moving across the sky. The shadows of the mountains on the moon are sharply defined.

Because the moon has no atmosphere, then there can be no wind on it. There is always a cloudless black sky, in which the stars shine even in the bright Sun. Air gives the blue color to the sky on Earth. Scattering the sun's rays, it prevents us from seeing the stars during the day, as it makes the background of the entire sky brighter than the stars.

Due to the absence of an atmosphere, the scorching rays of the Sun during the lunar day can raise surface temperatures. Moon up to plus 120?; but after sunset, the temperature drops rapidly and reaches minus 160 at night.

Since there is neither water nor air on the Moon, its surface does not erode or weather. Various irregularities on the lunar surface - its mountains and depressions - are best seen near the first and last quarter, when obliquely falling sun rays create elongated shadows there. From these shadows, scientists have measured the height of the lunar mountains: some of them reach 7000 m.

Give a lot to explore the surface Moon photographs taken at high magnification. On them you can see a wide darkish plain, which was called the Sea of ​​\u200b\u200brains, and along its edges - chains of mountains and individual ring mountains. Another part of the surface Moon It is completely covered with ring mountains and craters of various sizes. The diameter of the largest of them reaches 200 km.

But how could large craters or vast plains, bordered by mountain ranges, form? Science has not yet finally solved this question. Russian geologist A.P. Pavlov believed that once hot masses erupted in separate places from the bowels Moon to the surface and formed molten lakes and seas. Volcanic magma gradually solidified, piling up hardened rocks at the edges. In the middle of these spaces, the surface sank somewhat, forming vast plains.

Some scientists believe that the craters could have formed as a result of huge meteorites falling on the moon.

In addition to the vast plains, mountain ranges and numerous ring mountains that cover the surface, the photograph Moon one can see fissures, folds, and peculiar light streaks radiating from some of the large craters. Almost all major landforms on the Moon have been given different names.: for mountain ranges, the names of the earth are taken (Caucasus, Alps, Apennines, etc.), for craters - the names of famous scientists (Copernicus, Kepler, Tycho, etc.)

The lunar surface is lifeless and empty. Its feature is the complete absence of atmospheric effects that are observed on Earth. Night and day come instantly, as soon as the rays of the Sun appear.

Due to the lack of a medium for the propagation of sound waves, complete silence reigns on the surface.

The axis of rotation of the Moon is tilted only 1.5 0 from the normal to the ecliptic, so the Moon does not have any seasons, changes in the seasons. Sunlight is always nearly horizontal at the lunar poles, making these areas permanently cold and dark.

The lunar surface is changing under the influence of human activities, meteorite bombardments, exposure to high-energy particles (X-rays and cosmic rays). These factors do not have a noticeable effect, but during astronomical times they strongly “plow” the surface layer - regolith.

When a meteor particle hits the surface of the Moon, a miniature explosion occurs and particles of soil and meteorite matter are scattered in all directions. These particles mostly leave the gravitational field of the Moon.

The range of daily temperature fluctuation is 250 0 C. It ranges from 101 0 to -153 0 . But the heating and cooling of the rocks is slow. A rapid change in temperature occurs only during lunar eclipses. It was measured that the temperature changes from 71 to - 79 C per hour.

The temperature of the underlying layers was measured by radio astronomical methods, it turned out to be constant at a depth of 1 m and equal to -50 C at the equator. So the top layer is a good heat insulator.

Analysis of lunar rocks brought to Earth has shown that they have never been exposed to water.

The average density of the Moon is 3.3 g/cm 3 .

The period of revolution of the Moon around its axis is equal to the period of its revolution around the Earth, so it is observed from the Earth only on one side. The far side of the moon was first photographed in 1959.

The bright areas of the lunar surface are called continents and occupy 60% of its surface. These are rugged mountainous regions. The remaining 40% of the surface is the sea. These are depressions filled with dark lava and dust. They were named in the 17th century.

The continents are crossed by mountain ranges located along the coasts of the seas. The highest height of the lunar mountains reaches 9 km.

Lunar craters are mostly of meteorite origin. There are few volcanic ones, but there are also combined ones. The largest lunar craters have a diameter of up to 100 km.

Bright flashes were observed on the Moon, which may be associated with volcanic eruptions.

The Moon has almost no liquid core, as evidenced by the absence of a magnetic field. Magnetometers show that the Moon's magnetic field does not exceed 1/10,000 of Earth's.

Atmosphere:

Although the Moon is surrounded by a vacuum more perfect than that which can be created in terrestrial laboratory conditions, its atmosphere is vast and of high scientific interest.

During a two-week lunar day, atoms and molecules, knocked out by a series of processes from the lunar surface onto ballistic trajectories, are ionized by solar radiation and then driven by electromagnetic effects like plasma.

The position of the Moon in orbit determines the behavior of the atmosphere.

The dimensions of atmospheric phenomena were measured by a series of instruments placed on the lunar surface by the Apollo astronauts. But analysis of the data was hampered by the fact that the natural lunar atmosphere is so negligible that pollution from the gases emanating from Apollo significantly affected the results.

The main gases present on the Moon are neon, hydrogen, helium, and argon.

In addition to surface gases, a small amount of dust has been found circulating up to several meters above the surface.

The number of atoms and molecules in a unit volume of the atmosphere is less than a trillionth of the number of particles contained in a unit volume earth's atmosphere at sea level. The gravitational force of the moon is small enough to keep the molecules close to the surface.

Any body with a speed greater than 2.4 km / s will be released from the gravitational control of the moon. This speed is slightly higher than the average speed of hydrogen molecules at ordinary temperature. Dissipation of hydrogen occurs almost instantaneously. The dissipation of oxygen and nitrogen is slower, because these molecules are heavier. In astronomically short periods of time, the Moon is capable of losing all of its atmosphere, if it ever had one.

Now the atmosphere is replenished from interplanetary space.

M. Mendillo and D. Bomgardner (Boston University) after analyzing the results of observations of the complete lunar eclipse On November 29, 1993, they came to the conclusion that the lunar atmosphere is 2 times more extended (equal to 10 moon diameters) than previously thought.

It is maintained not by impacts of micrometeorites and elementary particles of the solar wind (protons and electrons) on the lunar soil, but by the impact of light and thermal photons of solar radiation on it.

The main components are sodium and potassium atoms and ions knocked out of the lunar soil. The atmosphere is very rarefied, but sodium atoms are easily excited and radiate strongly, so they are easy to detect. (Nature 5.10.1995).

Origin: According to prevailing modern theories The Moon formed together with the Earth from the same planetesimal. Scientists believe that the Moon was originally very close to the Earth, and J. Darwin wrote that the Moon was once in contact with the Earth and the period of revolution of two bodies was about 4 hours. But this assumption seems unlikely. Many believe that the Moon formed at a distance much less than half the present. In this case, tidal waves on Earth should have reached 1 km.

There are other theories. A new proof of the hypothesis that the Moon was formed from the collision of some body with the Earth has been found.

According to the lunar satellite "Clementine", processed at the Hawaiian University

those (USA), a map was made of the percentage of iron on the surface of the moon. It can vary from 0% in the mountains to 14% at the bottom of the seas. If the Moon had the same mineralogical composition as the Earth, then there would be much more iron. So it is unlikely that it was formed from the same protoplanetary cloud with the Earth.

Huge regions on the far side of the moon contain no iron at all, but are covered with anorthosite, a rock rich in aluminum. Pure anorthosite is rare on Earth.

Impact on Earth: Americans R. Bolling and R. Serveny studied data on

global temperature distribution obtained from satellites between 1797 and 1994. From the data it follows that the Earth is warm when the Moon is full, and cold - when the Moon is in a new moon. With its light on a full moon, the Moon warms the Earth by 0.02 0 C. Even such temperature changes can affect the Earth's climate. (Astronomy Now, May 1995).

1. Exploration of the moon in antiquity

2. Physical conditions on the moon

A. Lack of atmosphere

b. Change of lunar phases

3. The relief of the moon

A. First cards. Surface shape

b. Creation of craters. Meteorites.

V. The flight of spaceships, the study of the moon.

d. Lunar rocks.

4. Far side of the moon

5. Magnetism of the moon.

6. Man in the moon

MOON SONNET

Moon and lotus ... All verses of the East
You have been sung. Glorified the East
A radiant disk shining high,
Love and glory sweet flower.

Moon and lotus... exudes lotus

Soy gentle scent over the silence of the waters,

And the moonlight still pours quietly ...

But there is a rover on the moon today.

The moon was rediscovered by them,

And, having established a connection, he informed us,
That he found a piece of a meteorite,
That the flesh of the moon is basalt and diabase ...

Still the ancient moonlight pours,
But I am writing a sonnet in a new way.

Lodongiin Tudev

"ANCIENT" MOON

The moon is a natural satellite of the Earth and the closest celestial body to the Earth, and therefore it is best studied, but several millennia ago, with what amazement, primitive man followed the lunar disk! A pensive and mysterious luminary, a dim night sun, a ball wandering alone in the silent firmament of heaven - the Moon at all times and among all peoples in particular attracted human gazes and thoughts. The moon was subject to the vicissitudes of human opinion. Jules Verne, Cyrano de Bergerac and other writers, dreamers imagined, and some even claimed, that the Moon is inhabited by living beings and rich in fruitful life. Before the invention of the telescope, philosophers, quite naturally, were inclined to see the earth in the moon, similar to the one on which we live. When Galileo, pointing his first telescope at this sphere, found mountains and valleys there, similar to the various forms of relief of the surface of our planet, and vast gray plains that could easily be mistaken for seas, the similarity between these worlds and ours seemed obvious, and it was immediately inhabited not only by human beings, but also by various animals. The first maps were drawn, and it was agreed that the large dark spots be christened with the name of the "sea", which they still bear.

Astronomers, thinkers, were sure that rapid successes would follow the increase in telescopes, and in the reign of Louis XIV it was even supposed to build a "tube 100 thousand feet long for viewing animals existing on the Moon." But no matter how hard the opticians tried, their successes could not go far on a par with the imagination. When they began to clearly distinguish the surface of the lunar seas, it turned out that it was not liquid and not smooth, but sandy and uneven. Not a single real morph, not a single lake, not the slightest trace of the presence of water in any form, in the form of clouds, snow or ice, has been discovered on this luminary. No less careful observation of the stars and planets at the moment they are covered by the Moon passing before us showed, moreover, that the light of these luminaries, when they come into contact with the lunar edge, is not at all weakened or refracted, and that this ball is not surrounded by any noticeable atmosphere. The gradual lunar life dissipated like smoke, and little by little it became a habit to put in astronomical books the phrase: "The moon is a lifeless luminary." Today this has been proven both theoretically and practically. The moon is devoid of atmosphere and water, which cannot exist in liquid form without a dense atmosphere. Without an atmosphere, the existence of any organic life is impossible.

PHYSICAL CONDITIONS ON THE MOON

As already mentioned: the Moon is the closest celestial body to the earth, and therefore the best studied. The closest planets to us are about 100 times further away. The moon is four times smaller than the Earth, its radius is 1738 km, or 0.272 of the Earth's radius. Its mass is 81 times less than the Earth and is equal to 0.0123 Earth masses. The mass of the Moon is reliably determined from the motion of its artificial satellites, which are repeatedly launched into selenocentric orbits, i.e. orbits around the moon (from the Greek. "Selena" - the moon). Its average density is equal to 3.55*10 3 kg/m 3 or 0.6 of the density of the Earth, and the free fall acceleration on its surface is g=1.63 m/s 2, i.e. 6 times less than the earth, so that any object on the lunar surface weighs one times less than on Earth. As already noted, there is no atmosphere on the Moon that softens the scorching solar radiation and protects against cosmic rays and meteorite streams. There are no clouds, no water, no fogs, no rainbows, no dawns with dawn. Due to the absence of air and a gaseous shell, very curious phenomena occur on the moon. There is no twilight here, night is replaced by day and day is replaced by night instantly, like a lamp that instantly goes out and lights up in the dark. There is no gradual transition from warm to cold. The temperature on the moon immediately drops from the boiling point to the temperature of interplanetary space. The huge temperature fluctuations of the lunar surface from day to night are explained not only by the absence of an atmosphere, but also by the duration of the lunar day and lunar night, which corresponds to our two weeks. The temperature at the subsolar point of the Moon is +120°С, and at the opposite point of the night hemisphere -170°С. this is how the temperature changes during one lunar day! For the same reason, meteorites without braking hit the lunar surface with great speed, causing strong shaking of the soil and forming funnels.

Due to the absence of an atmosphere, there are no colors in the lunar sky. Throughout the night, which lasts two Earth weeks, and an equally long day with the scorching Sun over the Moon, the black sky is dotted with many stars that stand out clearly and completely non-flickering. The stars in the lunar sky are visible during the day as well as at night.

Several millennia ago, people watched in amazement as the moon grew and waned, like a living being, grew fat and dried up. Disappeared completely and steadily reborn again in the starry blackness of the sky. There was a steady pattern in this astonishing change, which manifested itself from the beginning of the century, which will remain unchanged until the end of time. And when people finally realized that there were four quarters between the two new moons, they took the most important step from a short measure of the time of the day to a longer one - a month. The periodic change of the lunar phases into the flesh and blood of human ideas about the world. It is no coincidence that the Moon in Sanskrit is called "mas", i.e. measuring instrument, it is no coincidence that the Latin "mecules" - month - is in close connection with the word "mekuura" - measure. It was the Moon, not the Sun, that became the first object of worship. The peoples of Central America have long had a lunar year - a measure of time designed to establish religious holidays. The lunar calendar was also used by the peoples inhabiting Mesopotamia. When determining church holidays, the lunar calendar is guided by Jews, Christians, who determine the onset of Easter according to it. The coincidence of the phases of the moon with a variety of manifestations of animate and inanimate nature: ebbs and flows in the seas, a decrease in temperature and abundant dews that usually fall on a clear moonlit night, increased growth of some plants and the lunar periodicity of the vital functions of the human body - all this has long worried people. Subsequently, the phases of the moon were associated with the concept of death and resurrection. With the stay of the month in the new moon, not only the growth of cereals is associated, but also the well-being of the herds and the health of children. So among the Central African tribe, when a new month appeared, mothers carried out their babies and showed their rebirth to the moon. When the Moon entered the last quarter, its influence, on the contrary, was considered unfavorable. It was better not to start new cases. All over the globe, farmers have a belief that it is necessary to sow when it is at a loss. At a certain period, the cult of the Moon occupied a central place in many religions. Now science, medicine point to the possible connection of some disorders of the human psyche with the phases of the moon. The moon can affect the human body, which is more than 80% water, just as it affects the seas and oceans.

The huge luminary of the lunar sky, the Earth, represents the same phases for the Moon as the Moon does for us, but in reverse order. During the new moon, the Sun illuminates the hemisphere of the Earth facing our satellite, and then there is a “full Earth”. During the full moon, on the contrary, the unlit hemisphere is turned towards our satellite, and then there is a “new Earth”. When the moon shows us the first quarter, the earth represents the last, and so on. Regardless of these phases, our ball appears to the Moon as rotating around its axis for 24 hours and 48 minutes, because. The moon returns to each earth meridian not earlier than after this period of time. Recall that the period of rotation of the Moon around its axis is 27.32 g (Earth days) and therefore it faces the earth with one hemisphere. Full moons are repeated after 29.53 g, which means that a solar day on the Moon lasts 29.53 g, i.e. about 14.8 g lasts a day and the same amount a night.

RELIEF OF THE MOON

Since the time of Galileo, the mapping of the moon began. The first detailed maps of the lunar surface were compiled by the outstanding Polish astronomer J. Hevelius (1611-1687) and published in 1647 in the work "Selenography" or "Description of the Moon". In 1651, the Italian astronomer J. Riccioli (1598-1671) also published a map of the Moon, compiled by him together with the Italian physicist F. Grimaldi. (1618-1663). It was on this map that the rounded lowlands were named for the first time by seas that have retained their names to this day: the Sea of ​​Tranquility, the Sea of ​​Clarity, the Sea of ​​Danger, the Sea of ​​Rains, the Sea of ​​Clouds, etc. Their sizes are from 200 to 1100 km across. "Sea" - lowlands in which there is not a drop of water. Their bottom is dark and relatively flat. The surface of the seas is complex and covered with dark matter, including hardened lava, once erupted from the lunar interior. The largest lowland, 2000 km long, is called the Ocean of Storms. The surface of the seas has folds and hills, as well as small pointed and rounded hills, which are the tops of low mountains, filled with subsequently hardened lava. The marginal zones of the seas, characteristic in their outlines, are called bays, and small isolated dark lowlands are called lakes. Seas and lakes occupy about 40% of the entire surface of the Moon visible from Earth, and the vast majority of them are located in its northern hemisphere. The rest (60%) of the lunar hemisphere is a mainland covered with both individual mountains and mountain ranges and ranges. Most of the mountain ranges stretch along the margins of the seas and bear earthly names proposed by J. Hevelius. So, the Sea of ​​​​Rains is bounded from the northeast by the Alps, from the east by the Caucasus, from the southeast by the Apennines, and from the south by the Carpathians. Some mountain ranges are named after scientists: the mountains of D'Alembert, the mountains of Leibniz, etc. The height of the mountains is different, individual mountain peaks - peaks - rise up to 9 km. The mountain slopes are cut by numerous gorges and cracks, and long valleys stretch between the mountains. The shape of the lunar mountains is mostly a round mountain with a hollow in the middle. But the basin is not always empty, it does not always turn out to be a newest crater: sometimes a whole mountain rises in its middle, and again with a depression, which turns out to be a newer crater, but rarely, rarely active with reddening inside, at its very bottom, lava. There are many on the moon and plateaus with steep slopes, wide and narrow cracks in the crust with a length of several tens and even hundreds of kilometers. It is better to study the lunar relief when it is obliquely illuminated by the sun's rays, especially not far from the terminator, which separates the daytime hemisphere of the Moon from the nighttime, i.e. near it, the shadows even from low mountains are very long and easily visible. It is very interesting to follow through a telescope for an hour how bright points light up near the terminator on the night side - these are the tops of the shafts of lunar craters. Gradually, a bright horseshoe emerges from the darkness - part of the crater shaft, but the bottom of the crater is still immersed in complete darkness, and finally the entire crater is outlined. It is clearly seen that the smaller the craters, the more of them. They are often arranged in chains and even "sit" on top of each other. Later craters, as already mentioned, were formed on the baths of older craters. A hill is visible in the center of the craters, in reality it is a group of mountains. The crater walls break off in terraces steeply inwards. The bottom of the craters lies below the surrounding area. The mountainous regions of the lunar surface are almost completely covered with many craters, and in a smaller number they are found in the seas. The sizes of craters are from 1 m to 250 km. Large and medium-sized craters, known since the time of the first telescopic observations of the moon, are named after scientists: Aristotle, Copernicus, Tycho, Herodotus, Timocharis, Hipparchus, Kepler, and others.