Relevance:

On April 12, our country remembers a grandiose event - a manned flight into space. At the lessons, we also discussed the topic of space, drew pictures. And the teacher asked us to prepare interesting reports about space. Therefore, I chose this particular topic, since it is interesting to me myself. And on the eve of this Cosmonautics Day holiday, this is relevant for us, I think that you will also be interested.

My assumptions:

At home, I took out the encyclopedia "Heavenly Bodies" and began to read. Then I asked myself, maybe the moon could fall on us? I replied that, probably, the Moon would fall if it approached the Earth. Or maybe something keeps her with the Earth, so she does not fall and does not fly away.

Purpose and objectives of my work:

I decided to study the literature in more detail, how the Moon was formed, how it affects the Earth, what connects it with the Earth, and why the Moon does not fly into space and does not fall to the Earth. And here's what I found out.

Introduction

In astronomy, a satellite is a body that revolves around a large body and is held by the force of its attraction. The Moon is the Earth's satellite. Earth is a satellite of the Sun. The Moon is a hard, cold, spherical celestial body, which is 4 times smaller than the Earth.

The Moon is the closest celestial body to Earth. If it were possible, then a tourist would walk to the moon for 40 years

The Earth-Moon system is unique in the solar system, since no planet has such a large satellite. The Moon is the only satellite of the Earth.

It is better visible to the naked eye than any planet through a telescope. Our satellite is fraught with many mysteries.

The moon is so far the only cosmic body that has been visited by man. The Moon revolves around the Earth in the same way that the Earth revolves around the Sun (see Fig. 1).

The distance between the centers of the Moon and the Earth is approximately 384467 km.

What does the moon look like?

The Moon is not at all like the Earth. There is no air, no water, no life. The concentration of gases near the surface of the moon is equivalent to a deep vacuum. Due to the lack of atmosphere, its gloomy dusty expanses heat up to + 120 ° C during the day and freeze at night or just in the shade up to - 160 ° C. The sky on the moon is always black, even during the day. The huge disk of the Earth looks from the Moon more than 3.5 times than the Moon from the Earth, and hangs almost motionless in the sky (see Fig. 2).

The entire surface of the moon is pitted with funnels, which are called craters. You can see them by looking at the moon on a clear night. Some craters are so large that they could fit a huge city. There are two main options for the formation of craters - volcanic and meteorite.

The lunar surface can be divided into two types: very old mountainous terrain (lunar mainland) and relatively smooth and younger lunar seas.

The lunar seas, which make up approximately 16% of the entire surface of the moon, are huge craters resulting from collisions with celestial bodies that were later flooded with liquid lava. The lunar seas were given names: the Sea of ​​Crises, the Sea of ​​Abundance, the Sea of ​​Tranquility, the Sea of ​​Rains, the Sea of ​​Clouds, the Sea of ​​Moscow and others.

Compared to the Earth, the Moon is very small. The radius of the moon is 1738 km, the volume of the moon is 2% of the volume of the Earth, and the area is approximately 7.5%

How was the Moon formed?

The Moon and the Earth are almost the same age. Here is one of the versions of the formation of the moon.

1. Shortly after the formation of the Earth, a huge celestial body crashed into it.

2. From the impact, it shattered into many fragments.

3. Under the influence of gravity (attraction) of the Earth, the fragments began to revolve around it.

4. Over time, the fragments gathered together, and the Moon was formed from them.

Moon phases

The moon changes its appearance every day. First, a narrow crescent, then the Moon grows fat and after a few days becomes round. For a few more days, the full moon gradually becomes smaller and smaller and again becomes like a sickle. The crescent moon is often called the month. If the sickle is turned with a convexity to the left, like the letter “C”, then the Moon is said to be “aging”. After 14 days and 19 hours after the full moon, the old month will disappear completely. The moon is not visible. This phase of the moon is called the “new moon”. Then, gradually, the Moon from a narrow crescent turned to the right turns back into the full Moon.

For the moon to “grow up” again, the same period of time is required: 14 days and 19 hours. Changing the appearance of the moon, i.e. the change of lunar phases, from full moon to full moon, occurs every four weeks, more precisely for 29 and a half days. This is a lunar month. It served as the basis for the compilation lunar calendar. During the full moon, the moon is turned to the Earth with the illuminated side, and during the new moon, the unlit side. Turning around the Earth, the moon turns to it either as a fully illuminated surface, or as a partially illuminated surface, or as a dark one. That is why the appearance of the Moon is constantly changing during the month.

Ebb and flow

The gravitational forces between the Earth and the Moon cause some interesting effects. The most famous of them is the tides of the sea. The difference between high and low tide levels open spaces ocean is small and amounts to 30–40 cm. However, near the coast, due to the incursion of a tidal wave onto a solid bottom, the tidal wave increases its height in the same way as ordinary wind waves of the surf.

Given the direction of rotation of the Moon around the Earth, it is possible to form a picture of the tidal wave following the ocean. The maximum amplitude of a tidal wave on Earth is observed in the Bay of Fundy in Canada and is 18 meters.

Moon exploration

The moon has attracted the attention of people since ancient times. The invention of telescopes made it possible to distinguish more small parts relief (surface shape) of the moon. One of the first lunar maps was compiled by Giovanni Riccioli in 1651, he also gave names to large dark areas, calling them “seas”, which we still use today. In 1881 Jules Janssen compiled a detailed "Photographic Atlas of the Moon".

With the advent of the space age, our knowledge of the moon has increased significantly. The Moon was first visited by the Soviet spacecraft Luna-2 on September 13, 1959.

For the first time, it was possible to look at the far side of the Moon in 1959, when the Soviet station Luna-3 flew over it and photographed part of its surface invisible from the Earth.

The American program of manned flight to the moon was called "Apollo".

The first landing took place on July 20, 1969, and the first person to set foot on the surface of the moon was the American Neil Armstrong. Six expeditions have been to the moon, but in last time it was back in 1972, because expeditions are very expensive. Each time, two people landed on it, who spent up to three days on the moon. New expeditions are currently being prepared.

Why doesn't the moon fall to the earth?

The moon would instantly fall to the Earth if it were stationary. But the Moon does not stand still, it revolves around the Earth.

When we throw an object such as a tennis ball, gravity pulls it towards the center of the earth. Even thrown from high speed the tennis ball will still fall to the ground, but the picture will change if the object is much further away and moving much faster.

My experience:

I asked this question to my dad and he explained it to me with a simple example. We tied an ordinary eraser to a thread. Imagine that you are the Earth, and the eraser is the moon, and start spinning it. The eraser on the thread will literally break out of your hand, but the thread will not let it go. The moon is so far away and moving so fast that it never falls in the same direction. Even falling constantly, the moon will never fall to the earth. Instead, it moves around the earth in a constant path.

If we rotate the eraser very strongly, the thread will break, and if we rotate it slowly, the eraser will fall.

We conclude: if the moon moved even faster, then it would overcome the gravity of the earth and fly away into space, if the moon moved more slowly, gravity would pull it to the earth. This precise balance of gravity creates what we call an orbit, where the smaller celestial body is constantly revolving around the larger one.

The force that keeps the Moon from “running away” as it spins is the Earth's gravity. And the force that prevents the Moon from falling to the Earth is the centrifugal force that occurs when the Moon rotates around the Earth.

Circulating around the Earth, the Moon moves in orbit at a speed of 1 km / s, that is, slowly enough not to leave its orbit and “fly away” into space, but also fast enough not to fall to Earth.

By the way...

You will be surprised, but in fact the Moon ... is moving away from the Earth at a speed of 3-4 cm per year! The movement of the Moon around the Earth can be imagined as a slowly unwinding spiral. The reason for such a trajectory of the Moon is the Sun, which attracts the Moon 2 times stronger than the Earth.

Why then does the moon not fall on the sun? But because the Moon, together with the Earth, rotates, in turn, around the Sun, and the attractive action of the Sun is spent without a trace on constantly transferring both of these bodies from a direct path to a curved orbit.

- The Moon itself does not glow, it only reflects the sunlight falling on it;

- The moon rotates around its axis in 27 Earth days; during the same time it makes one revolution around the Earth;

- The moon, revolving around the earth, always faces us on one side, its reverse side remains invisible to us;

- The moon, moving along its orbit, gradually moves away from the Earth by about 4 cm per year.

- The force of gravity on the Moon is 6 times less than on Earth.

Therefore, it is much easier for a rocket to take off from the Moon than from the Earth.

It is possible that soon on distant interplanetary flights spaceships will be sent not from the Earth, but from the Moon.

Since the beginning of this century, China has announced its readiness to explore the moon, as well as to build several manned lunar bases there. After this statement, the space organizations of the leading countries, and in particular the USA (NASA) and ESA (European Space Agency) launched their space programs again.

What will come of it?

Let's see in 2020. It was for this year that George Bush planned to land people on the moon. This date is ten years ahead of China, since their space program said that the creation of habitable lunar bases and landing people on them would take place only in 2030.

The moon is the most studied celestial body, but for a person it still holds a lot of mysteries: perhaps it is the base of extraterrestrial civilizations, perhaps life on Earth would be completely different if there was no moon, perhaps in the future a person will settle on the moon ...

Conclusions:

So, we found out that the Moon is a natural satellite of the Earth, it revolves around our planet and, together with the Earth, moves in orbit around the Sun;

- the question of the origin of the moon is still controversial;

The changes in the shape of the moon are called phases. They exist only for us

One of my assumptions turned out to be correct, the Moon is really holding something, and this is the Earth's gravity and centrifugal force.

And my other assumption that the Moon will fall if it approaches the Earth is not entirely correct. The moon will fall to the Earth when the moon stops rotating, is stationary, then the centrifugal force will not work.

Studying encyclopedias and the Internet, I learned a lot of new and interesting things. I will definitely share these discoveries with my classmates in the lesson about the world around us.

We managed to unravel some of the mysteries of the Moon, but this did not make it less interesting and attractive!

References:

1. “Space. Supernova Atlas of the Universe”, M., “Eksmo”, 2006.

2. New school encyclopedia"Heavenly bodies", M., "Rosmen", 2005

3. "Why" Children's Encyclopedia, M., "Rosmen", 2005

4. “What is it? Who it?" children's encyclopedia, M.,” Pedagogy -

Press" 1995

5. Internet - reference books, pictures about space.

Completed: 3B class student

Khaliullin Ildar

Supervisor: Sakaeva G.Ch.

MOU secondary school №79, Ufa

Department of Education of the Administration of the Kemerovo Municipal District

Xregional scientific and practical conference

"World of Discovery"

Section "Geography, geology »

Why doesn't the moon fall to earth?

research project

Semenov Lavr Yurievich,

1st grade student "B"

MBOU "Yagunovskaya secondary school"

Supervisor:

Kalistratova

Svetlana Borisovna,

teacher primary school

MBOU "Yagunovskaya secondary school"

2016

Content

Introduction ……………………………………………………………………………. 3

Chapter 1

1.1. Study of sources …………………………………………………………… 5

1.2. Moon observations...................................................................................... 7

Chapter 2. Organization and results of the study ……………………………...9

Conclusion……………………………………………………………………….. 13

List of literature and Internet resources……………………………………….. 14

Introduction

I love everything that has to do with space. I love watching the stars, finding constellations, so we chose this topic for research.

Kemerovo State University has amazing place- planetarium. It is included in the list of planetariums in Russia, of which there are 26 in total, as well as in the list of planetariums in the world. "Founder" of our planetarium, teacher, candidate of physical and mathematical sciences of Kemerovo State University, Kuzma Petrovich Matsukov is better than anyone, understands "the affairs of the stars." The planetarium hosts guided tours that reveal the mysteries of the cosmos, the birth of the universe and stars. Here you can see a picture of a real starry sky! With the help of the projector of the starry sky under the dome of the planetarium, we can see about five thousand stars, planets, the sun and the moon.

Some planets have many moons, while others don't. We decided to figure out what a satellite is. Of course, we were interested in the Moon, since it is a satellite of our Earth.

Having asked Kuzma Petrovich why the Moon always hangs in the sky and does not fly away, they found out that the Earth has an amazing property: it attracts everything to itself. But the Moon hangs in the sky and for some reason does not fall to the Earth. Why? Let's try to find the answer to this question.

Purpose of the study: find out why the moon does not fall to the earth.

Research objectives:

1. Study various sources on this issue (encyclopedias, the Internet), visit the planetarium of the Kemerovo State University.

2. Find out how the Moon was formed, how the Moon affects the Earth, what links the Moon to the Earth.

3. Conduct a study and, based on the data obtained, find out why the Moon does not fall to the Earth.

Research hypothesis: it is likely that the moon will fall if it approaches the earth. But maybe there is something that keeps the moon at a distance from the earth, so the moon does not fall to the earth.

Chapter 1

1.1 Study of sources

Before we look for the answer to the question “What is, in fact, the Moon?” Let's conduct a small survey among adults (5 people) and children (5 people), and find out how deep their knowledge in this area is.

3 people - wrong.

4 people - right;

1 person - wrong.

Citizens of which country first landed on the moon? (Americans)

0person - right;

5 people - wrong.

5 people - right;

0person - wrong.

What was the name of the self-propelled vehicle that traveled on the surface of the moon? ("Lunokhod")

3 people - right;

2 people - wrong.

5 people - right;

0person - wrong.

We know that the Earth is a magnet. Why doesn't the Moon, the Earth's satellite, fall to the Earth? (It revolves around the earth

1 person - right;

4 people - wrong.

4 people - right;

1 person - wrong.

Where did the craters on the moon come from? (from collisions with meteorites)

2 people - right;

3 people - wrong.

5 people - right;

0person - wrong.

After conducting a survey, we found out that adults can answer questions about the moon, but children cannot. So we continued our research.

The word "moon" means "bright". In ancient times, people considered the moon to be the goddess - the patroness of the night.

The Moon is the only natural satellite of the Earth. The second brightest object in the earth's sky after the Sun.Astronomers now use modern laser-beam instruments to determine the distance between the Earth and the Moon to within a few centimetres.The Moon is at a distance of 384,400 km from the Earth. Traveling there on foot would take nine years!By car, we would need to go to the moon without stopping for more than six months.

The lunar globe is much smaller than the earth: in diameter - almost 4 times, and in volume - 49 times. From the substance of the globe, 81 balls can be made, each of which would weigh as much as the moon.

We can always see only one side of the moon. A sort of "small" disk, the diameter of which is 3480 km. Approximately half the area of ​​all of Russia.The period of rotation of the Moon around its axis coincides with the period of revolution of the Earth, which is 28 and a half days, so the Moon always faces the Earth on one side.

The moon revolves around the Earth not strictly in a circle, but in a flattened circle - an ellipse. And when the moon gets as close as possible, the distance between the earth and the moon shrinks356,400 kilometers. This minimum approach of the Moon to the Earth is calledperigee . The maximum distance is calledapogee and equals whole406,700 kilometers.

There is no atmosphere, so humans cannot breathe on the Moon. Surface temperature from -169 °C to +122 °C.

Gray spots on the moon in the old days were considered seas. It is now known that there is not a drop of water on the Moon, and there is no air shell - the atmosphere. The lunar "seas" are deep depressions covered with gray volcanic rocks. Some of the lunar craters were formed when iron or stone bodies - meteorites - fell on the Moon from interplanetary space. The bright parts of the Moon are its mountainous regions.

American astronauts have landed on the moon. Our lunar rovers controlled from Earth also told a lot of interesting things about it. Machine guns and astronauts delivered lunar soil to Earth. The moon is very small, and therefore the force of gravity on it is also small. Astronauts on the Moon weighed about 1/6 of their usual weight on Earth.

Moon 4.5 billion years - about the same as the Earth. It was formed as a result of the collision of the Earth with one of the small planets. The planet was destroyed, and the Moon was formed from its fragments and began to gradually move away from the Earth. The distance between it and the Earth is increasing at about the same rate as fingernails grow.

As the Moon revolves around the Earth, the force of gravity acts on our seas. This attraction causes ebb and flow.

1.2 Observations of the Moon.

Let's watch the moon, and we will see that its appearance changes every day. First, a narrow crescent, then the Moon grows fat and after a few days becomes round. After a few more days, the full moon gradually becomes smaller and smaller and again becomes like a sickle. The crescent moon is often called the month. If the sickle is turned with a bulge to the left, like the letter "C", then the Moon is said to be "aging". After 14 days and 19 hours after the full moon, the old month will disappear completely. The moon is not visible. This phase of the moon is called the "new moon". Then gradually the Moon, from a narrow crescent turned to the right (if you mentally draw a straight line through the ends of the crescent, you get the letter "P", i.e. the month "grows"), turns again into the full Moon. Sometimes during the new moon, the moon obscures the sun. At such moments it happens solar eclipse. If the Earth casts a shadow on the Moon during a full moon, then moon eclipse. For the Moon to “grow up” again, the same period of time is required: 14 days and 19 hours. Changing the appearance of the moon, i.e. the change of lunar phases, from full moon to full moon (or from new moon to new moon) occurs every four weeks, more precisely, for 29 and a half days. This is a lunar month. It served as the basis for compiling the calendar. It is possible to calculate in advance when and how the Moon will be visible, when there will be dark nights, and when there will be bright ones. During the full moon, the moon is turned to the Earth with the illuminated side, and during the new moon, it is unlit. The moon is a solid, cold celestial body that does not emit its own light, it shines in the sky only because it reflects the light of the Sun with its surface. Turning around the Earth, the Moon turns to it either as a fully illuminated surface, or as a partially illuminated surface, or as a dark one. That is why the appearance of the Moon is constantly changing during the month.

Chapter 2. Organization and results of the study

Today, astronomers imagine the structure solar system like this: in the center of it is the Sun, and the planets circle around it, as if attached, as if tied. There are eight in total - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Neptune and Uranus. Why, after all, the planets run around the Sun, as if tied? They are indeed tied, only this connection is invisible. Isaac Newton formulated a very important law - the law of universal gravitation. He proved that all the bodies of the Universe - the Sun, the planets with their satellites, individual stars and star systems - are attracted to each other. The strength of this attraction depends on the size celestial bodies and from the distances between them. The smaller the distance, the stronger the attraction. The greater the distance, the weaker the attraction. Let's do some experiments.

Experience 1. Let's try to jump in place. What came of it? That's right, we flew up a few centimeters and sank back to the ground. Why don't we jump up and fly high into the sky, and then into space? Yes, because we are also tied to our planet by the same force of attraction.

Experience 2. Let's take the ball. It does not fly anywhere, it is at rest, in our hand. We are standing on the floor. We release the ball from our hands, it falls to the floor.

Experience 3. We pick up a paper sheet, throw it up, but it also smoothly falls to the floor.

Watching gravity in nature. We see snow, raindrops fall on the ground. Even icicles do not grow up, but down to the ground.

Conclusion. The earth holds on its surface everything that is on it with a really powerful attraction. It holds not only us and everything living on Earth, but also all objects, stones, rocks, sands, water of the oceans, seas and rivers, the atmosphere surrounding the Earth.

Then why doesn't the moon fall to the earth?

To begin with, we conducted a survey among the children and their parents on the website "Kemdetki". The question was asked: "Why do you think the Moon does not fall to the Earth?" Here are some of the answers:

1. Dasha, 7 years old: "Because there is air in the sky, and he holds the moon."

2. Anya, 7 years old: “Because there is no gravity in zero gravity, it’s a planet!”

3. Olya, 9 years old: “Because the Moon revolves around the Earth in its orbit and cannot leave it.”

4. Matvey, 5 years old: “The moon is a satellite of the Earth. And in the Earth there is a core-magnet and it attracts.

5. Olya, 5 years old: "Holding on to the air."

6. Alice, 7 years old: “Because her sky is holding her and she cannot push off ...”.

7. Roma, 6 years old: "Because she stuck to the night ...".

8. Masha, 6 years old: “Where does she fall here? We don't have enough space here."

Having studied articles in encyclopedias and the Internet, they found out that the Moon would instantly fall to the Earth if it were stationary. But the Moon does not stand still, it revolves around the Earth. During rotation, a force is formed, which scientists call centripetal, that is, tending to the center, and centrifugal, running away from the center. We can verify this for ourselves by conducting a series of simple experiments.

Experience 1. Tie a thread to a regular felt-tip penand start spinning it.A felt-tip pen on a thread will literally break out of our hand, but the thread will not let go. A centrifugal force acts on the felt-tip pen, trying to throw it away from the center of rotation. So onThe centrifugal force acts on the moon, which does not allow it to fall to the Earth. Instead, it moves around the Earth in a constant path. If we rotate the felt-tip pen very strongly, the thread will break, and if we rotate it slowly, the felt-tip pen will fall. Therefore, if the Moon moved even faster, then it would overcome the attraction of the Earth and fly away into space, if the Moon moved more slowly, gravity would attract it to the Earth.

F1 - centrifugal force (running from the center)

F2- centripetal force (seeking the center)

Experience 2. Let's take dad's hands, as in a round dance. Without letting go of his hands, let's start running around dad, looking at his face, and let dad turn after us. Dad is, and we will be the moon. If you spin really, really fast, you can even fly without touching the floor with your feet. And so that we do not fly away to the wall, dad will have to hold us very tightly. It's the same in heaven. The hands of the father - the Earth strongly grabbed the Moon and do not let her go.

Experience 3. You can also give an example with the attraction "Carousel", which is located in the City Garden of Kemerovo. The rotation speed of the Carousel is specially calculated, and if the centrifugal force were less than the chain tension, otherwise it would end in disaster.

Experience 4. A washing machine - an automatic machine will also be an example. The laundry that is washed in it is attracted to the walls of its drum, when it moves with acceleration, the laundry is spun out, and only falls when the drum stops.

Conclusion. So is the Moon. If it did not revolve around the Earth, then, for sure, it would fall on it. But centrifugal forces do not allow her to do this. And the Moon cannot escape either - the Earth's gravitational force keeps it in orbit.

Conclusion

So, having studied the literature on this issue and visiting the planetarium of the Kemerovo State University, we found out:

That the Moon is the only natural satellite of the Earth.Moon 4.5 billion years - about the same as the Earth.

With the help of observations, we have noticed that the appearance of the moon changes every day. Such changes in the shape of the moon are calledphases.

We also concluded that the Moon is held by the Earth by the force of attraction between the bodies. The force that keeps the moon from "running away" as it rotates isEarth's gravity (centripetal) . And the force that prevents the moon from falling to the Earth -is the centrifugal force , which occurs when the moon rotates around the earth. If the Moon moved faster, then it would overcome the gravity of the Earth and fly away into space, if the Moon moved more slowly, the force of gravity would pull it towards the Earth.Rotating around the Earth, the Moon moves in orbit at a speed of 1 km / s, that is, slowly enough not to leave its orbit and "fly away" into space, but also fast enough not to fall to Earth.

Literature and Internet resources

New school encyclopedia "Heavenly bodies", M., Rosmen, 2005.

"Why" Children's Encyclopedia, M., Rosmen, 2005

"Why doesn't the moon fall to Earth?" Zigunenko S.N., Why books, 2015

Rancini. J. “Space. Supernova Atlas of the Universe”, M.: Eksmo, 2006.

- "Kids!" site for parents of the Kemerovo region.

Wikipedia

Website for children. Why"

Website "Astronomy and laws of space"

"How simple!"

Here I decided to make a selection of answers to the most tricky questions about the Moon. Write new questions and your answers in the comments at the bottom of the page!

1. Why doesn't the moon fall to earth?

For the same reason that all the planets do not fall into the Sun - the centrifugal force that occurs when the Moon moves around the Earth compensates for the gravitational force between the Earth and the Moon. But if the Moon is stopped relative to the Earth, it will fall.

2. The sun pulls the moon 2.2 times stronger than the earth. Why doesn't the Moon fly away from the Earth towards the Sun?

This is because the Moon and the Earth move together in orbit around the Sun and the centrifugal force generated by the movement of the Moon around the Sun compensates for the gravitational force of the Sun. If, for example, the Earth is removed, the Moon will revolve around the Sun in almost the same orbit in which it revolves with the Earth around the Sun.

3. The moon moves away from the earth by about 4 cm annually. Perhaps this is due to the fact that the Sun attracts the Moon more strongly than the Earth?

Not certainly in that way. The removal of the Moon from the Earth is a consequence of tidal acceleration. The meaning of the phenomenon is the following. The Earth revolves around its axis with a period of 24 hours, while the Moon revolves around the Earth with a period of 27.3 days. As a result, the gravitational field of the Earth pushes the Moon (individual parts of the rapidly rotating Earth drag the slowly flying Moon along), that is, it gives its energy to the movement of the Moon around the Earth. This energy accelerates the Moon, which means it raises its orbit.

4. And what, the Moon will then completely fly away from the Earth?

It will not fly far :) Taking the energy of the Earth's rotation to raise its orbit, the Moon slows down the rotation of the Earth. Because of this, the Earth slows down the rotation around its axis and the geostationary orbit (that is, the orbit in which the speed of the satellite over the planet is equal to the speed of the planet's rotation) of the Earth rises. In the end, the Moon will be in geostationary orbit and the phenomenon of full synchronization will come in which the Moon and Earth will look at each other with only one side. This is a stable state and will continue for billions of years. And only in the very distant future, the influence of our Sun (or some other object) can slow down the mutual rotation of the Moon-Earth pair and the Moon will fall to the Earth.

5. Have Americans been to the moon or not?

The article talks about why the Moon does not fall to the Earth, the reasons for its movement around the Earth and some other aspects of the celestial mechanics of our solar system.

The beginning of the space age

The natural satellite of our planet has always attracted attention. In ancient times, the Moon was the object of worship of some religions, and with the invention of primitive telescopes, the first astronomers could not tear themselves away from contemplating the majestic craters.

A little later, with the discovery in other areas of astronomy, it became clear that not only our planet, but also a number of others have such a celestial satellite. And Jupiter has 67 of them! But ours is the leader in size in the entire system. But why doesn't the moon fall to the earth? What is the reason for its movement along the same orbit? We will talk about this.

Celestial mechanics

First, you need to understand what orbital movement is and why it occurs. According to the definition used by physicists and astronomers, an orbit is a movement into another object that is much larger in mass. For a long time it was believed that the orbits of the planets and satellites have a circular shape as the most natural and perfect, but Kepler, after unsuccessful attempts to apply this theory to the movement of Mars, rejected it.

As is known from the course of physics, any two objects experience mutual so-called gravity. The same forces affect our planet and the moon. But if they are attracted, then why does the moon not fall to the Earth, as would be the most logical thing?

The thing is that the Earth does not stand still, but moves around the Sun in an ellipse, as if constantly “running away” from its satellite. And that, in turn, have an inertial speed, which is why it travels again in an elliptical orbit.

The simplest example that can explain this phenomenon is a ball on a rope. If you spin it, it will hold the object in one plane or another, and if you slow down, it will not be enough and the ball will fall. The same forces act and the Earth drags it along, not allowing it to stand still, and the centrifugal force developed as a result of rotation holds it, preventing it from approaching a critical distance.

If the question of why the Moon does not fall to the Earth is given an even simpler explanation, then the reason for this is the equal interaction of forces. Our planet attracts the satellite, forcing it to rotate, and the centrifugal force, as it were, repels.

Sun

Such laws apply not only to our planet and satellite, they are subject to all the rest. In general, gravity is a very interesting topic. The movement of the planets around is often compared to a clockwork, it is so accurate and verified. And most importantly, it is extremely difficult to break it. Even if you remove a few planets from it, then the rest with very highly likely, will be rearranged into new orbits, and the collapse with falling on the central star will not occur.

But if our luminary has such a colossal gravitational effect even on the most distant objects, then why does the Moon not fall on the Sun? Of course, the star is at a much greater distance than the Earth, but its mass, and hence gravity, is an order of magnitude higher.

The thing is that its satellite also moves in orbit around the Sun, and the latter does not act separately on the Moon and the Earth, but on their common center of mass. And on the Moon there is a double influence of gravity - stars and planets, and after it the centrifugal force that balances them. Otherwise, all satellites and other objects would have burned out long ago in a hot luminary. This is the answer to the frequent question of why the moon does not fall.

Sun movement

Another fact worth mentioning is that the Sun also moves! And along with it, our entire system, although we are accustomed to believing that outer space is stable and unchanging, with the exception of the orbits of the planets.

If you look more globally, within the framework of systems and their entire clusters, you can see that they also move along their trajectories. In this case, the Sun with its "satellites" revolves around the center of the galaxy. If you conditionally imagine this picture from above, then it looks like a spiral with many branches, which are called galactic arms. In one of these arms, along with millions of other stars, our Sun also moves.

The fall

But still, if you ask such a question and dream up? What conditions are needed under which the Moon will crash into the Earth or go on a journey to the Sun?

This can happen if the satellite stops rotating around the main object and the centrifugal force disappears, also if something changes its orbit and adds speed, for example, a collision with a meteorite.

Well, it will go to the star, if purposefully somehow stop its movement around the Earth and give the initial acceleration to the luminary. But most likely, the Moon will simply gradually rise into a new curved orbit.

To summarize: the Moon does not fall to the Earth, because, in addition to the attraction of our planet, it is also affected by the centrifugal force, which, as it were, repels it. As a result, these two phenomena balance each other, the satellite does not fly away and does not crash into the planet.

Looking at the Moon, many children wonder: how does it stay in its place and why does it not fall to the Earth? The question is quite logical, because artificial satellites that a person launches really fall, but the natural satellite of our planet has a simple secret.

What prevents the moon from falling on us

The force of gravity acts on the Moon - the gravitational field of the Earth. Because of the same force, we do not float in weightlessness, but walk on the ground. Gravity could pull the Moon towards it, but it doesn't because it orbits the Earth. In the process of such movement, another force arises - centrifugal, which repels the night star from our planet.

Think of the amusement park rides that go in circles. Can you move to the center of the carousel while it is spinning? It won’t work: you will be very strongly repelled from it, as if someone is pressing on your chest or you are being blown away by a powerful wind. The same thing happens to the Moon as it moves around the Earth.

What happens if you push the ball in two opposite directions at the same time? He will stay put. In the same way, the balance of forces that attract and repel the Moon allows it to stay on its path for millions of years, along which it runs around the planet.

Why doesn't the moon fall into the sun

The Moon is the closest satellite to the Sun, and the main star of our galaxy also has a powerful force that can attract it - this is the Sun's magnetic field. It is several times stronger (compared to the Earth's field) pulls the Moon towards itself.

But the moon will not fall on this burning ball for the same reason. It revolves not only around the Earth: together with the Earth, the satellite moves around the Sun, and centrifugal force arises between them. It pushes the Moon away from the Sun and compensates for its attraction.

Because of this, other planets of our solar system and their satellites will not fall on the Sun - they also rotate, and therefore they are simultaneously attracted and repelled. If the movement stopped, they could fall, but for billions of years this cosmic mechanism has been working without failure.

Why are human-made satellites falling to Earth?

The small "moons" that are launched into space by human hands must revolve around the Earth at a certain speed and at a certain distance in order to stay in their orbit. If the speed is greater, they will be torn out of the gravitational field and carried into the Universe, and if less, they will deorbit and fall.

In space, there are many factors that can slow down a satellite: substances from the Earth's atmosphere that are found even on high altitude, the solar wind - the particles that the Sun releases into space, the gravity of the Earth and other celestial bodies in our galaxy. In addition, when creating satellites, scientists sometimes make mistakes and honestly admit that they do not know why they spacecraft are falling.

But be that as it may, with satellites created by man, you can be sure in the Moon: it will definitely not fall to Earth.