The Moon is the celestial body located closest to the Earth, which is its natural satellite and the brightest object after the Sun. In addition, it is also the only object in the solar system that humans have set foot on.
The moon has attracted attention at all times. People have looked at it for centuries, admiring the lunar craters, trying to study its origin and laws. The moon rotates in the same direction as most celestial bodies. It moves around the Earth at a speed of about 1 km/s. Since there is no atmosphere there, there is no water, no air, no weather on the Moon. And the temperature has a fairly wide range: from –120 °C to +110 °C. The force of gravity is 6 times less than Earth's (1.62 m/s2). As early as 1610, Galileo Galilei used telescopic equipment to observe the lunar surface and discover various depressions and craters.
Extended darkish spots, or “Moon Seas” as they are called, occupy about 40% of the visible lunar relief. In the old days, meteorite and asteroid attacks on the lunar surface were commonplace. It is even possible that the Moon took upon itself all the blows of celestial bodies that were intended for our Earth! But she, like a kind of shield, repelled all attacks. Perhaps it is the Moon that we should say thank you for the fact that life on our planet did not disappear from the fall of some meteorite or asteroid. Now, the frequency of collisions of celestial bodies with the Moon is practically zero, but the craters that we can observe on the surface of the Moon remain forever, as a kind of reminder of the merits of our faithful satellite.
Structure of the Moon
The mass of the Earth's satellite is 81 times less than our planet. To study the lunar structure, various methods were used, including seismic ones. The upper layer of the lunar surface is represented by the crust, the thickness of which reaches 60 km. The crust consists of the rock basalt. In marine and continental areas, its composition has significant differences. The mantle - located under the lunar crust, is divided into the upper - 250 km, the middle - 500 km and the lower - 1000 km. Up to this level, the substance of the subsoil is in a solid state, and is a cold and powerful lithosphere, with undamped seismic vibrations. Nearing the end of the lower mantle boundary, the temperature increases, approaching the melting point, so seismic waves are quickly absorbed. This part of the satellite is the lunar asthenosphere, in the center of which there is a liquid core consisting of iron sulfide with a radius of 350 km. The temperature in it ranges from 1300K to 1900K, with a mass of no more than 2% of the mass of the entire Moon.
It is known that the Moon is turned to the Earth, only on one side, so everyone has long dreamed of finding out what secrets the other side of the Moon hides. By itself, the Moon does not glow. It’s just that the sun’s rays, reflected from the Earth, illuminate its different parts. In this regard, the phases of the moon are also explained. It is turned to us with its dark side and moves in orbit between the Sun and Earth. Every month there is a new moon. The next day, a bright crescent of a “renewed” Moon appears in the western sky. The rest of the Moon receives virtually no light reflected from the Earth. In a week, half of the Moon's disk can be observed. After 22 days, the last quarter is observed. And on the 30th day the new moon comes again.
Characteristics of the Moon
Mass: 0.0123 Earth masses, that is 7.35 * 1022 kg
Diameter at the equator: 0.273 times the diameter of the Earth, i.e. 3476 km
Axis tilt: 1.55°
Density: 3346.4 kg/m3
Surface temperature: –54 °C
Distance from satellite to planet: 384400 km
Speed around the planet: 1.02 km/s
Orbital eccentricity: e = 0.055
Orbital inclination to the ecliptic: i = 5.1°
Gravity acceleration: g = 1.62 m/s2
The Moon contains a metallic core! This conclusion was reached by Rene Weber of NASA's Marshall Space Flight Center and Rafael Garcia of the University of Toulouse after re-examining data obtained during the Apollo lunar mission in the late 60s and early 70s. Perhaps the discovery will shed new light on the evolution of the Earth's satellite.
As part of the Apollo space program, four seismometers were delivered to the Moon, which recorded the seismic activity of the celestial body until 1977. It turned out that seismic shocks on the Moon occur much less frequently than on Earth. Moreover, since the surface of the earth's satellite is dotted with craters left over from collisions with small cosmic bodies, this distorts instrument signals and makes vibrations of the lunar crust less noticeable.
For a long time, information obtained from the Moon through seismic sensors was considered practically useless to scientists. However, over the past forty years, methods for analyzing seismic data have changed significantly. In addition, Weber and Garcia were able to take into account the “error” arising from craters. As a result, they came to the conclusion that the Moon, like the Earth, has a hot metal core. Its diameter is approximately 330-360 kilometers, it is surrounded by a partially molten shell with a diameter of approximately 480 kilometers. Inside the core, in turn, there is a solid iron core with a diameter of approximately 240 kilometers.
"We applied robust seismology to this data set, resulting in the first direct evidence of the lunar core," said cosmologist Rene Weber.
The researchers also analyzed the seismograms by processing the data into groups, which made it possible to determine the source of the seismic activity. By determining the trajectories of seismic waves and the characteristics of their reflection from the inner layers of the Moon, they were able to identify the composition and structure of the layers of the lunar core at various depths.
Scientists believe that due to the large amount of iron in the depths of the Moon, it has a powerful magnetic field. Although the lunar core is in many ways similar to the earth's, their structure is still different. As we know, the earth's core has a solid inner and outer liquid layer. And in the core of the Moon there is also a solid third layer, the boundary between the mantle and the outer liquid nuclear shell.
The Moon is believed by astrophysicists to have formed approximately 4.5 billion years ago as a result of the collision of the Earth with a large space object the size of the planet Mars. Hypothetically, this shock “knocked out” a piece from the Earth consisting of the crust of the molten mantle, which later turned into the Moon. Moreover, studies carried out at the Kola superdeep well established that the composition of the peninsula’s rocks is almost 90 percent identical to that of lunar rocks. It turns out that this happened in the place where the layers of crust were located, which later made up the Kola Peninsula.
Until recently, it was believed that the Moon was a “cold” celestial body, but a mystery for scientists was the presence of a weak (residual) magnetic field on it. The fact is that, as scientific theories say, its source on planets is tectonic activity. For example, near the Earth it is created by the movement of molten metal in the core.
In 1959, it was discovered that the Moon's magnetic field is not uniform. As research by scientists from the Massachusetts Institute of Technology has shown, the Moon at an early stage of its existence had a liquid core, and its magnetic field was similar to that of the Earth.
Now this phenomenon seems to be explained. In addition, since the mantle of the Moon, apparently, is also hot and convection of matter occurs in it (read more about this in the article “Volcanoes - the alarm level is growing”), then volcanic activity may be present on our satellite. Indeed, the Japanese Kaguya probe discovered on the surface of the Moon, near the Marius Hills plateau, a hole with a diameter of about 65 meters and a depth of about 80 meters. According to scientists, this may indicate the existence on the Earth's satellite of tunnels laid by hardened volcanic lava flows. This hypothesis is also confirmed by the presence of winding grooves of unknown origin on the surface of the satellite.
The research results were presented at a recent conference of the American Astrophysical Union. Its participants noted that knowledge about the composition of the lunar core will also help to better understand how our Earth was formed and how it will evolve in the future.
The Moon is the most accessible body in the world if you suddenly want to look at some space object with the naked eye. People have been very interested in the history of the appearance of dark and light spots on its surface throughout the history of mankind. What caused the formation of these strange features?
Children's fairy tales tell us about what is made of cheese. But, as is true for other bodies in the solar system, rock is a more realistic candidate. The Moon's surface has dead volcanoes, impact craters and lava flows. Some of them can be seen without special instruments.
Ancient scientists believed that the dark areas of the Moon could be oceans. And that’s why they were called in Latin “mare”, which means “sea”. These areas are truly oceans in a certain sense. Instead of water, the lunar seas contain solidified lava. During the Moon's youth, its crust was warm enough to form volcanoes. Although at the same time it quickly cooled and hardened. Lava could break through the crust when large enough asteroids fell on the Moon.
There is much evidence of such asteroid impacts on the surface of the Moon. Early in the history of the solar system, all planets and moons suffered from them. This was the so-called period of heavy bombardment. Plate tectonics and surface erosion have obscured much of the evidence for this period. In addition, the atmosphere helped burn up some small meteorites, preventing them from reaching the surface. However, the Moon does not have all these factors. Therefore, the history of the Solar System is preserved on the surface of the Moon unchanged.
The thickness of the Moon's crust is 60-100 km. Regolith on the surface can be shallow - up to 3 meters in the seas, and up to a depth of 20 meters in the hills.
Beneath the surface
Like the Earth, the Moon boasts a crust, mantle, and core. Deep within its interior, the Moon may have a solid iron core surrounded by molten metal. The outer core of the Moon can be up to 500 km in size. However, the small inner core makes up only about 20 percent of the Moon, compared with the 50 percent core of other rocky bodies.
Most of the Moon's internal structure consists of the lithosphere, which is about 1000 km thick. As this area melted early in the Moon's evolution, it supplied magma to the lava plains on its surface. However, over time, the magma cooled and hardened, thereby stopping volcanism on the Moon.
The Moon is the second densest body in the Solar System after the satellite. The separation of its inner layers was probably caused by the crystallization of the magma ocean shortly after its formation.
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Diameter: 3476 km;
Surface area: 37,900,000 km²;
Volume: 2.2×10 10 km³;Weight: 7.35×10 22 kg;
Density t: 3346 kg/ m³;
Rotation period : 27.3 days;
Circulation period: 27.3 days;
Distance from Earth: 385,000 km;
Orbital speed: 1.02 km/ With ;
Equator length: 10,914 km;
Orbital inclination : 5.15°;
Acceleration free fall: 1.62 m/s²;
Satellite : Earth
For many millennia Moon attracts a person's gaze. Ancient peoples, observing the Moon, personified it with a deity - as a night world luminary. The Romans called the satellite the Moon and Diana, the Greeks - Selene, the ancient Egyptians - Iyah. While observing the Moon, ancient people noticed the periodicity of changes in lunar phases - it grew and waned, disappeared completely and was certainly reborn again. The fickle queen of the night became the first measure of time; the first lunar calendar was compiled, which is still used today.
Moon- the only natural satellite of the Earth. The second brightest object in the earth's sky after and the fifth largest natural satellite of the planets. It is also the first and only celestial body, besides the Earth, visited by man. The average distance from the Moon to the Earth is 385,000 km, or just over one light second. The Earth's satellite is 50 times smaller than its planet, and its radius is 1738 km (27% of the Earth's radius). Our planet, due to gravitational forces, causes the Moon to rotate in an elliptical orbit at a speed of 1.02 km/s. At the moment, the parameters of the lunar orbit are known with high accuracy. Our satellite makes a full revolution around it in 27.322 days or 27 days 7 hours and 43 minutes. This is the time that is called lunar month, which differs by 3 days from the calendar. Also, the gravitational attraction between the Earth and the Moon is the cause of the earth's ebbs and flows.
Our satellite was formed 4.36 billion years ago. According to one version, the Moon and the Earth
formed at the same time from a gas-dust cloud. There is also
assumption that the Moon was formed as a result of the collision of the Earth
with another object
Lunar surface
When observing the Moon, you can see dark spots of various shapes on its surface. These spots date back to the 17th century. began to be called seas. In those days, it was believed that there was water on the Moon, which means there should be seas and oceans, like on Earth. They were given names that are used to this day: Ocean of Storms, Sea of Cold, Sea of Rain, Sea of Clouds, Sea of Tranquility, etc. However, already in 1753, the Croatian astronomer Ruđer Bošković proved that the Moon does not have an atmosphere, so on its surface Liquid water cannot be present, since in the absence of atmospheric pressure it would immediately evaporate. Lunar seas, which make up approximately 16% of the entire surface of the Moon, are huge craters created by collisions with celestial bodies that were later flooded with liquid lava.
Lunar landscape original and unique. The moon is all covered with craters of different sizes in diameter - from hundreds of kilometers to a couple of millimeters. There are two theories about the origin of these craters:
- volcanic theory - was put forward back in the 80s of the 18th century. German astronomer Johann Schröter, according to which lunar craters were formed as a result of powerful volcanic eruptions on the surface;
- meteorite theory - the craters were formed during the formation of the satellite when the Moon was subject to meteorite bombardment. Recesses formed on the lunar surface, which became known as craters.
A significant part of the lunar surface is dotted with craters of various sizes.
The photo shows the Copernicus crater, which was formed about 800 million years ago.
Its diameter is 93 km, and its depth extends almost 4 km.
Fragment of a section of the Moon's surface
The moon has no atmosphere, it is simply a round, rocky celestial body orbiting around. The sky above the Moon is always black, even during the day. There is no air-gas shell that would trap heat on our satellite. Therefore, on the Moon, as well as on, there are sharp temperature fluctuations at night and during the day. During the day, the lunar surface heats up to +120 °C, and at night or even in the shadow it cools down to −160 °C.
The full Moon reflects only 7% of the sunlight falling on it. Since the Moon does not glow itself, but only reflects sunlight, only the illuminated part of the lunar surface is visible from Earth. The Moon orbits the Earth, and thus the angle between the Moon and the Sun changes; we observe this phenomenon as a cycle of lunar phases.
Change of lunar phases. The period of time between full moons is called
lunar month and is 27.32 days
Structure of the Moon
The moon consists from the crust, upper mantle, middle mantle, lower mantle (asthenosphere) and core. The density of the Moon is 3346 kg/m³ - the same as that of the Earth's mantle. This means that our satellite either does not have a dense iron core, or it is very small. Indeed, the shell of the inner core is rich in iron, it has a radius of only 240 km, while the liquid outer core consists mainly of liquid iron with a radius of approximately 300-330 kilometers. By mass, the lunar core makes up only 2% of the total mass of the satellite and consists of iron alloyed with small amounts of sulfur and nickel. Around the core there is a partially molten boundary layer with a radius of about 480-500 kilometers. Like all planets, the Moon has the largest volume in its structure in its mantle. It can be divided into three components: the upper one with a thickness of 400 km, the middle one with a thickness of 700 km and the lower one with a thickness of approximately 200 km. The Moon's mantle is not completely melted like the mantle and therefore does not have volcanoes.
One of the sensations of lunar exploration was the discovery of a thick crust 60-100 km thick. This indicates the existence in the past on the Moon of the so-called magma ocean, in the depths of which melting and formation of the crust took place during the first 100 million years of its evolution. We can conclude that the Moon and Earth had a similar origin. However, the tectonic regime of the Moon differs from the plate tectonics regime characteristic of the melting basaltic magma used to build up the lunar crust. That's why she's so fat.
Internal structure of the Moon.
Core - 330 km;
Mantle - 1300 km;
Kora - 60-100 km
First steps on foreign land
Man has always been attracted to space. As soon as he looked at the night sky, he began to imagine himself as a traveler through the endless depths of the dark unknown, imagining how he would finally reach other worlds, walk on the extraterrestrial surface, perhaps find a new home for himself on other planets. However, no matter how hard humanity has tried to date, it has not yet been able to reach these new worlds. There are many reasons: some of them are located at enormous, by earthly standards, distances from our planet, while others have unsuitable conditions for staying on them, etc. However, the main reason is distance. Even the closest planet from Earth takes a modern probe at least eight months to get there. Who would dare to take such a risky and long journey, because it is still unknown how space will influence a person during such a long flight.
Nevertheless, the man did not give up, and although he had not yet managed to reach the nearest planets, he was still able to make his first space flight to the nearest and only Earth's satellite - the Moon.
Exploration of the Moon using spacecraft began on September 14, 1959, with the collision of the Luna-2 automatic station with the surface of our satellite. Until this point, the only method of exploring the Moon was by observing the Moon. Galileo's invention of the telescope in 1609 was a major milestone in astronomy, particularly in the observation of the Moon. Galileo himself used his telescope to study the mountains and craters on the lunar surface. At that time, in addition to the arms race, between the USA and the USSR there was an equally important rivalry in terms of lunar exploration. In 1962, the 35th US President John Kennedy formulated the main US mission in space as landing on the Moon.
Lunokhod-1—the first automatic rover on the Moon
Man on the Moon
The Earth's satellite has attracted people's attention since prehistoric times. The Moon is the most visible object in the sky after the Sun, and therefore it has always been attributed the same significant properties as the daylight star. Centuries later, worship and simple curiosity were replaced by scientific interest. The waning, full and waxing Moon are the objects of the most intense study today. Thanks to the research of astrophysicists, we know a lot about the satellite of our planet, but much remains unknown.
Origin
The moon is a phenomenon so familiar that the question of where it came from practically does not arise. Meanwhile, the origin of our planet’s satellite is one of its most significant secrets. Today there are several theories on this matter, each of which can boast of both the presence of evidence and arguments in favor of its inconsistency. The data obtained allow us to identify three main hypotheses.
- The Moon and Earth formed from the same protoplanetary cloud.
- The fully formed Moon was captured by the Earth.
- The formation of the Moon was caused by the collision of the Earth with a large space object.
Let's look at these versions in more detail.
Co-accretion
The hypothesis of the joint origin (accretion) of the Earth and its satellite was recognized in the scientific world as the most plausible until the early 70s of the last century. It was first put forward by Immanuel Kant. According to this version, the Earth and the Moon were formed almost simultaneously from protoplanetary particles. The cosmic bodies represented a double system.
The Earth began to form first. After it reached a certain size, particles from a protoplanetary swarm began to circle around it under the influence of gravity. They began to move in elliptical orbits around the nascent object. Some particles fell to Earth, others collided and stuck together. Then the orbit gradually began to approach more and more circularly, and the embryo of the Moon began to form from a swarm of particles.
Pros and cons
Today, the co-origin hypothesis has more refutations than evidence. It explains the identical oxygen isotope ratio of the two bodies. The reasons put forward within the framework of the hypothesis for the different composition of the Earth and the Moon, in particular, the almost complete absence of iron and volatile substances on the latter, are questionable.
Guest from afar
In 1909, Thomas Jackson Jefferson See put forward the gravitational capture hypothesis. According to it, the Moon is a body that formed somewhere in another region of the solar system. Its elliptical orbit intersected the trajectory of the Earth. At the next approach, the Moon was captured by our planet and became a satellite.
In support of the hypothesis, scientists cite fairly common myths of the peoples of the world, telling about the time when the Moon was not in the sky. The theory of gravitational capture is also indirectly confirmed by the presence of a solid surface on the satellite. According to Soviet research, the Moon, which does not have an atmosphere, if it has been revolving around our planet for several billion years, should have been covered with a multi-meter layer of dust coming from space. However, today it is known that this is not observed on the surface of the satellite.
The hypothesis can explain the small amount of iron on the Moon: it could have formed in the zone of the giant planets. However, in this case there should be a high concentration of volatile substances on it. In addition, based on the results of modeling of gravitational capture, its possibility seems unlikely. A body with such a mass as the Moon would more likely collide with our planet or be thrown out of orbit. Gravitational capture could only occur if the future satellite passed very close. However, even in this option, the destruction of the Moon under the influence of tidal forces becomes more likely.
Giant Clash
The third of the above hypotheses is considered the most plausible today. According to the giant impact theory, the Moon is the result of the interaction of the Earth and a fairly large space object. The hypothesis was proposed in 1975 by William Hartman and Donald Davis. They suggested that a protoplanet called Theia collided with the young Earth, which had managed to gain 90% of its mass. Its size corresponded to modern Mars. As a result of the impact that hit the “edge” of the planet, almost all of Theia’s matter and part of the earth’s matter was thrown into outer space. From this “building material” the Moon began to form.
The hypothesis explains the modern speed as well as the angle of inclination of its axis and many physical and chemical parameters of both bodies. The weak point of the theory is the reasons it gives for the low iron content on the Moon. To do this, before the collision, complete differentiation must have occurred in the depths of both bodies: the formation of an iron core and a silicate mantle. To date, no confirmation has been found. Perhaps new data about the earth’s satellite will clarify this issue. True, there is a possibility that they can refute the hypothesis of the origin of the Moon accepted today.
Basic parameters
For modern people, the Moon is an integral part of the night sky. The distance to it today is approximately 384 thousand kilometers. This parameter changes slightly as the satellite moves (range - from 356,400 to 406,800 km). The reason lies in the elliptical orbit.
Our planet's satellite moves through space at a speed of 1.02 km/s. It completes a full revolution around our planet in approximately 27.32 days (sidereal or sidereal month). Interestingly, the attraction of the Moon by the Sun is 2.2 times stronger than by the Earth. This and other factors influence the motion of the satellite: shortening the sidereal month, changing the distance to the planet.
The axis of the Moon has an inclination of 88°28". The rotation period is equal to a sidereal month and that is why the satellite is always turned to our planet with one side.
Reflective
It can be assumed that the Moon is a star very close to us (in childhood, this idea could have occurred to many). However, in reality it does not have many of the parameters inherent in bodies such as the Sun or Sirius. Thus, moonlight, sung by all romantic poets, is only a reflection of the sun. The satellite itself does not radiate.
The phase of the moon is a phenomenon associated with its lack of its own light. The visible part of the satellite in the sky is constantly changing, sequentially passing through four stages: new moon, waxing moon, full moon and waning moon. These are the stages of the synodic month. It is calculated from one new moon to the next and lasts on average 29.5 days. The synodic month is longer than the sidereal month, since the Earth also moves around the Sun and the satellite always has to make up some distance.
Many faces
The first phase of the moon in the cycle is the time when for an observer on earth there is no satellite in the sky. At this time, it faces our planet with its dark, unlit side. The duration of this phase is one to two days. Then a month appears in the western sky. The moon is only a thin crescent at such a time. Often, however, you can observe the entire disk of the satellite, but less bright, colored in gray. This phenomenon is called the ashen color of the Moon. The gray disk next to the bright crescent is the part of the satellite illuminated by rays reflected from the Earth's surface.
Seven days from the beginning of the cycle, the next phase begins - the first quarter. At this time, the Moon is exactly half illuminated. A characteristic feature of a phase is a straight line separating the dark and illuminated areas (in astronomy it is called a “terminator”). Gradually it becomes more convex.
On the 14th-15th day of the cycle, the full moon occurs. Then the visible part of the satellite begins to decrease. On the 22nd day the last quarter begins. During this period, an ashy color can also often be observed. The angular distance of the Moon from the Sun becomes less and less and after approximately 29.5 days it is completely hidden again.
Eclipses
Several other phenomena are associated with the peculiarities of the satellite’s motion around our planet. The plane of the Moon's orbit is inclined to the ecliptic by an average of 5.14°. This situation is not typical for such systems. As a rule, the satellite's orbit lies in the plane of the planet's equator. The points where the Moon's trajectory intersects the ecliptic are called the ascending and descending nodes. They do not have precise fixation and are constantly, albeit slowly, moving. In about 18 years, the nodes travel the entire ecliptic. Due to these features, the Moon returns to one of them after a period of 27.21 days (called the draconic month).
The passage of a satellite through the points of intersection of its axis with the ecliptic is associated with such a phenomenon as an eclipse of the Moon. This is a phenomenon that rarely makes us happy (or sad) but has a certain periodicity. An eclipse occurs at the moment when the full moon coincides with the passage of a satellite of one of the nodes. Such an interesting “coincidence of circumstances” occurs quite rarely. The same is true for the coincidence of the new moon and the passage of one of the nodes. At this time, a solar eclipse occurs.
Observations by astronomers have shown that both phenomena are cyclical. The length of one period is a little more than 18 years. This cycle is called a saros. During one period, 28 lunar and 43 solar eclipses occur (of which 13 are total).
The influence of the night star
Since ancient times, the Moon has been considered one of the rulers of human destiny. According to thinkers of that period, it influenced character, relationships, mood and behavior. Today, the effect of the Moon on the body is studied from a scientific point of view. Various studies confirm that there is a dependence of certain behavioral characteristics and health status on the phases of the night light.
For example, doctors in Switzerland, who have been monitoring patients with problems with the cardiovascular system for a long time, have found that the waxing Moon is a dangerous period for people prone to heart attacks. Most of the attacks, according to their data, coincided with the appearance of a new moon in the night sky.
There are a large number of similar studies. However, collecting such statistics is not the only thing that interests scientists. They tried to find explanations for the identified patterns. According to one theory, the Moon has the same effect on human cells as it does on the entire Earth: it causes changes in the water-salt balance, membrane permeability, and hormone ratio as a result of the influence of the satellite.
Another version focuses on the influence of the Moon on the planet’s magnetic field. According to this hypothesis, the satellite causes changes in the electromagnetic impulses of the body, which entails certain consequences.
Experts who are of the opinion about the enormous influence of the night luminary on us recommend building your activities in accordance with the cycle. They warn: lanterns and lamps that block moonlight can harm human health, because because of them the body does not receive information about the change of phases.
On the Moon
After getting acquainted with the night star from Earth, we will walk along its surface. The Moon is a satellite that is not protected from the sun's rays by the atmosphere. During the day, the surface heats up to 110 ºС, and at night it cools down to -120 ºС. In this case, temperature fluctuations are characteristic of a small zone of the crust of a cosmic body. Very low thermal conductivity does not allow the interior of the satellite to warm up.
We can say that the Moon is lands and seas, vast and little explored, but with their own names. The first maps of the satellite's surface appeared in the seventeenth century. Dark spots, previously mistaken for seas, turned out to be low plains after the invention of the telescope, but retained their name. The lighter areas on the surface are “continental” zones with mountains and ridges, often ring-shaped (craters). On the Moon you can find the Caucasus and the Alps, the Seas of Crisis and Tranquility, the Ocean of Storms, the Bay of Joy and the Swamp of Rot (bays on the satellite are dark areas adjacent to the seas, swamps are small spots of irregular shape), as well as the mountains of Copernicus and Kepler.
And only after that the far side of the Moon was explored. This happened in 1959. The data obtained by the Soviet satellite made it possible to map the part of the night star hidden from telescopes. The names of the greats also appeared here: K.E. Tsiolkovsky, S.P. Koroleva, Yu.A. Gagarin.
Completely different
The lack of an atmosphere makes the Moon so different from our planet. The sky here is never clouded, its color does not change. On the Moon there is only a dark dome of stars above the astronauts' heads. The sun rises slowly and moves leisurely across the sky. A day on the Moon lasts almost 15 Earth days, and the same is the length of the night. A day is equal to the period during which the Earth's satellite makes one revolution relative to the Sun, or a synodic month.
There is no wind or precipitation on the satellite of our planet, and there is also no smooth flow of day into night (twilight). In addition, the Moon is constantly under threat from falling meteorites. Their number is indirectly indicated by the regolith covering the surface. This is a layer of debris and dust up to several tens of meters thick. It consists of crushed, mixed and sometimes fused remains of meteorites and lunar rocks destroyed by them.
When looking at the sky, you can see the Earth hanging motionless and always in the same place. A beautiful, but almost never changing picture is explained by the synchronization of the Moon’s rotation around our planet and its own axis. This is one of the most wonderful sights that the astronauts who first landed on the surface of the Earth's satellite had a chance to see.
Famous
There are times when the Moon is the “star” not only of scientific conferences and publications, but also of all kinds of media. Of great interest to a large number of people are some rather rare phenomena associated with the satellite. One of them is a supermoon. It occurs on those days when the night star is at the smallest distance from the planet, and in the full moon or new moon phase. At the same time, the night star becomes visually 14% larger and 30% brighter. In the second half of 2015, the supermoon can be observed on August 29, September 28 (on this day the supermoon will be the most impressive) and October 27.
Another curious phenomenon is associated with the periodic entry of the night luminary into the earth's shadow. The satellite does not disappear from the sky, but turns red. The astronomical event was called the Blood Moon. This phenomenon is quite rare, but modern space lovers are lucky again. Blood Moons will rise over the Earth several times in 2015. The last of them will appear in September and will coincide with a total eclipse of the night star. This is definitely worth seeing!
The night luminary has always attracted people. The moon and the full moon are central images in many poetic essays. As scientific knowledge and methods of astronomy developed, the satellite of our planet began to interest not only astrologers and romantics. Many facts have become clear since the first attempts to explain the lunar “behavior”; a large number of the satellite’s secrets have been revealed. However, the night star, like all objects in space, is not as simple as it might seem.
Even the American expedition could not answer all the questions posed to it. At the same time, every day scientists are learning something new about the Moon, although often the data obtained raises even more doubts in existing theories. This was the case with hypotheses about the origin of the Moon. All three main concepts that were recognized in the 60-70s were refuted by the results of the American expedition. Soon the giant collision hypothesis became the leading one. Most likely, many amazing discoveries related to the night star await us in the future.