Ebb and flow is the periodic rise and fall of the water level in the oceans and seas. Twice during the day, with an interval of about 12 hours and 25 minutes, the water near the coast of the ocean or the open sea rises and, if there are no barriers, sometimes floods large spaces - this is a tide. Then the water goes down and recedes, exposing the bottom - this is the ebb. Why is this happening? Even ancient people thought about this, they noticed that these phenomena are associated with the moon. The main cause of the tides was first pointed out by I. Newton - this is the attraction of the Earth by the Moon, or rather, the difference between the attraction of the Moon of the entire Earth as a whole and its water shell.
Ebb and flow explained by Newton's theory
The attraction of the Earth by the Moon is made up of the attraction of the individual particles of the Earth by the Moon. The particles that are in this moment closer to the moon, are attracted by it stronger, and more distant - weaker. If the Earth were absolutely solid, then this difference in the force of attraction would not play any role. But the earth is not absolutely solid, therefore, the difference in the attractive forces of particles located near the surface of the Earth and near its center (this difference is called the tide-forming force) displaces the particles relative to each other, and the Earth, primarily its water shell, is deformed.
As a result, on the side that faces the Moon, and on its opposite side, the water rises, forming tidal protrusions, and excess water accumulates there. Due to this, the water level in other opposite points of the Earth at this time decreases - there is a low tide here.
If the Earth did not rotate, and the Moon remained motionless, then the Earth, together with its water shell, would always retain the same elongated shape. But the Earth rotates, and the Moon moves around the Earth in about 24 hours and 50 minutes. With the same period, tidal protrusions follow the Moon and move along the surface of the oceans and seas from east to west. Since there are two such protrusions, a tidal wave passes over each point in the ocean twice a day with an interval of about 12 hours and 25 minutes.
Why is the height of the tidal wave different
In the open ocean, the water rises slightly during the passage of a tidal wave: about 1 m or less, which remains almost imperceptible to sailors. But off the coast, even such a rise in the water level is noticeable. In bays and narrow bays, the water level rises much higher during high tides, since the coast prevents the movement of the tidal wave and water accumulates here during the entire time between low tide and high tide.
The largest tide (about 18 m) is observed in one of the bays on the coast in Canada. In Russia, the highest tides (13 m) occur in the Gizhiginskaya and Penzhinskaya bays of the Sea of Okhotsk. In inland seas (for example, in the Baltic or Black), the tides are almost imperceptible, because masses of water moving along with the ocean tidal wave do not have time to penetrate into such seas. But all the same, in every sea or even lake, independent tidal waves arise with a small mass of water. For example, the height of the tides in the Black Sea reaches only 10 cm.
In the same area, the height of the tide is different, since the distance from the Moon to the Earth and the greatest height of the Moon above the horizon change over time, and this leads to a change in the magnitude of tide-forming forces.
Tides and Sun
The sun also influences the tides. But the tidal forces of the Sun are 2.2 times less than the tidal forces of the Moon. During the new moon and full moon, the tidal forces of the sun and moon act in the same direction - then the highest tides are obtained. But during the first and third quarters of the Moon, the tidal forces of the Sun and Moon counteract, so the tides are smaller.
Tides in the air shell of the Earth and in its solid body
Tidal phenomena occur not only in the water, but also in the air shell of the Earth. They are called atmospheric tides. Tides also occur in the solid body of the Earth, since the Earth is not absolutely solid. Vertical oscillations of the Earth's surface due to tides reach several tens of centimeters.
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 gravitational pull of the Moon is stronger on the side of the Earth that faces the Moon, and weaker on the opposite side. Therefore, the surface of the Earth, and especially the oceans, are stretched towards the Moon. If we looked at the Earth from the side, we would see two bulges, and both of them are directed towards the Moon, but are on opposite sides of the Earth. This effect is much stronger in ocean water than in solid crust, so the water bulges more. And since the Earth rotates much faster than the Moon moves in its orbit, moving the bulges around the Earth once a day gives two highest point high tide.
Origin hypotheses
Hypotheses and facts
Any considered model of the formation of the Moon must not only comply with physical laws, but also explain the following circumstances:
The average density of the Moon is 3.3 g/cm3, significantly inferior to the average density of the Earth - 5.5 g/cm3. The reason is that the Moon has a very small iron-nickel core - it makes up only 2-3% of the total mass of the satellite (according to NASA's Lunar Prospector mission). The metal core of the Earth makes up about 30% of the mass of the planet.
In addition to iron deficiency, the Moon has a very low content of volatile elements, such as hydrogen, nitrogen, fluorine, and inert gases, compared to the Earth. Conversely, on the Moon there is some excess of relatively refractory elements, such as titanium, uranium and thorium.
Rocks of the lunar crust and rocks earth's crust and the mantle are almost identical in the ratio of stable oxygen isotopes 16O, 17O, 18O (this ratio is sometimes called the “oxygen signature”). For comparison, meteorites from different parts solar system(including the so-called Martian meteorites) have completely different ratios of oxygen isotopes. This identity indicates that the Earth and the Moon (or at least the surface of the Moon) formed from the same layer of planetesimals - on the same distance from the sun.
The moon has a powerful solid crust 60-80 kilometers thick (several times thicker than the earth's crust), formed from anorthositic rocks - melting products of the lunar mantle. Therefore, it is believed that the Moon was once heated to complete melting. The earth is believed to have never been completely molten.
The Moon and the Earth have an unusually high, satellite-to-planet mass ratio of 1/81, compared to the other satellites of the planets in the solar system. (Above - only Charon and Pluto, but Pluto, as you know, is no longer a planet);
The Moon-Earth system has an unusually high angular momentum (second, again, only to the Charon-Pluto system).
The plane of the Moon's orbit (an inclination of 5° to the ecliptic) does not coincide with the equatorial plane of the Earth (an inclination of 23.5° to the ecliptic).
So, the following hypotheses were put forward:
Hypothesis of centrifugal separation: a piece of matter separated from the rapidly rotating proto-Earth under the action of centrifugal forces, from which the Moon was then formed. (This hypothesis is jokingly referred to as the “daughter hypothesis”). Capture Hypothesis: Earth and Moon formed independently, in different parts of the solar system. When the Moon passed close to the Earth's orbit, it was captured by the Earth's gravitational field and became the Earth's satellite. (This hypothesis is jokingly referred to as the "marital" hypothesis.)
Co-Formation Hypothesis: The Earth and Moon formed at the same time, in close proximity to each other. (Jokely, the "sister" hypothesis). Evaporation hypothesis: from the molten proto-Earth, significant masses of matter were evaporated into space, which then cooled down, condensed in orbit and formed the proto-Moon.
The Many Moon Hypothesis: Several small moons were captured by the Earth's gravity, then they collided with each other, collapsed, and the current Moon was formed from their fragments.
Collision hypothesis: the proto-Earth collided with another celestial body, and the Moon was formed from the material ejected during the collision.
Does the moon really affect our body? How and why is this happening?
The influence of the moon is undeniable. Of course, our native planet Earth has the greatest influence on a person, but the influence of other planets cannot be ruled out.
In our time, no one doubts that solar processes are reflected in the human body. At the same time, the influence of the Moon is undeservedly questioned. But the Moon, although much smaller than the Sun, is much closer to the Earth. The mass/distance ratio indicates a slightly greater influence of the Moon on objects on Earth.
It has long been noticed by scientists that the tides are controlled by the Moon. Lunar gravity causes the ocean level to rise by 1.5 meters, and in narrow bays this value reaches 12-16 meters. Even the solid shell of the Earth reacts to the movement of the Moon - it rises by 50 centimeters (such a rise occurs quite evenly, so we do not notice it). Therefore, it is not surprising that the human body, consisting of 80% of the liquid, is subject to lunar influence.
In addition, the Moon also affects the Earth's magnetic field, but about the danger magnetic storms we have all heard.
What do we feel when the moon is waxing and when it is waning?
On the growing moon, a person feels a surge of strength, optimism, readiness to cope with any task and confidence in your abilities. On the waning - on the contrary, a breakdown, weakness, a desire to quit everything. At this time, there is the greatest number of appeals of people in a depressed state.
In this regard, any projects should be started on the growing moon, and completed on the waning moon. This, of course, does not mean that you need to have time to crank out your project during the same lunar month. It is simply desirable to take this moment into account and break down your projects into stages, which should be adjusted to the lunar calendar.
In accordance with this, on the growing moon, it is worth starting health courses related to strengthening the body, moisturizing the skin - in general, any procedures related to absorbing the new. Whereas on the waning moon, you need to get rid of everything that is no longer needed: various cleansings are carried out (skin, digestive system, etc.). At the same time, it is important to remember that this does not apply to hair cutting - in this case, we are not so much getting rid of unnecessary hair ends as we are forming a new hairstyle - and this is a creative process! And you need to start it on the growing moon.
Waxing Crescent:
1 phase (1-7 lunar days). The beginning of the phase is the New Moon. The Moon and Sun are on the same side of the Earth and their gravitational forces are summed up. Maximum tides and ebbs. It is best for the body to start wellness procedures. This is the time when male power reaches its maximum.
Phase 2 (8-15 lunar days). The beginning of the phase is the first quarter. The body is full of energy and active. It is best to prescribe active training for this phase, maximum physical activity is possible.
Waning moon:
3 phase (16-22 lunar days). The beginning of the phase is the Full Moon. The Moon opposes the Sun and their gravitational forces oppose. Minimum tides, least storms and floods. The female force is active, the male is weakened. Energy saturation, emotions are bright, the unconscious is activated. This is a good time for creativity. Surgical interventions and injuries are dangerous for the body at this time, since the organs are full-blooded and blood clotting is poor. In addition, microorganisms are also active - the risk of infection is increased. There is also an increase in the birth and death rates. The first is due to the influence of the moon on the amniotic fluid, and the second is due to the influence on the blood (more heart attacks occur and malignant tumors are activated). In addition, bursts of suicides are noted on the full moon.
4 phase (23-29, 30 lunar days). The beginning of the phase is the last quarter.
At this time, you need to complete all projects and prepare new ones. The body is weakened and active loads are contraindicated.
Research shows that the new moon is the most peaceful time, while the full moon is the most hectic. This is well illustrated in children's groups, when researchers analyzed the performance of students in grades 5, 7, and 9. In each of the surveyed groups, there was a sharp drop in academic performance during the full moon and a rise in academic performance at the new moon.
The same can be seen in the analysis of the statistics of the Ministry of Internal Affairs: at the beginning of the lunar cycle, there are few violations and they are not the most severe (theft, fraud, etc.), while during the full moon the number of crimes increases sharply and they become more serious.
We also conducted our own small study: we analyzed data on people who sought help from a psychologist. It turned out that if we compare the dates of their calls, we can find the following distribution:
If we combine these data by lunar phases, it turns out even more clearly:
It turns out that 75% of people who turned to a psychologist did it on the waning moon, after the full moon. At the same time, the peak of calls falls on the full moon itself and a week after it. Thus, the description of the lunar phases given above is confirmed.
Is a full moon dangerous?
There is no particular danger. Each person is influenced not only by the Moon, but by a fairly large number of factors. The full moon rather creates a certain background that is favorable for all kinds of deviations in behavior, but does not completely determine them. That is, for example, for excitable people, nervous system which is highly susceptible to outside influences, the full moon is really not the easiest time. In such people, irritability increases, they suffer from insomnia, and become more prone to impulsive actions. Children are especially affected by the full moon, so the main recommendations will be for them.
Play noisy games before bed
Watch action movies and horror stories
Go far from home
Attend noisy events, competitions that cause great excitement
Walk more before going to bed, ventilate the room
Do I need to adjust to the moon phases? How?
It is not necessary to adjust, but it is desirable to take into account. As I already mentioned, each person is influenced by many factors and therefore it is impossible to adjust to all of them at the same time. But at the same time, it is still worth getting acquainted with the influence of the lunar phases on the body. This knowledge can be useful if you rely on it as a general guide.
MINISTRY OF EDUCATION AND SCIENCE OF THE RUSSIAN FEDERATION
federal state budgetary educational institution
higher vocational education
Siberian State Aerospace University
named after academician M.F. Reshetnev"
Scientific and educational center
"Institute of Space Research and High Technologies"
Department of Technical Physics
Report on educational (introductory) practice
Influence of the Moon as a natural satellite on the planet Earth
Direction: 011200.62 "Physics"
Performed:
3rd year student of group BF12-01
Persman Kristina Viktorovna
Supervisor:
Candidate of Physical and Mathematical Sciences, Associate Professor
Parshin Anatoly Sergeevich
Krasnoyarsk 2014
INTRODUCTION
1Origin of the Moon
2Moon movement
3Moon Shape
4Phases of the Moon
5Internal structure of the moon
RESEARCH METHOD
1 Ebb and flow
2Earthquakes and the Moon
RESULTS OF THE STUDY
CONCLUSION
INTRODUCTION
The Moon, by its influence, has a very great influence on the planet Earth and has a very large role in its, and most importantly, our existence, no less than the Sun. To understand its role in our lives, let's jump back to 4.5 billion years ago, when the solar system was still young, and the Earth did not yet have a moon. Our planet flew around the Sun alone, bombarded by comets, asteroids, as if in a giant cosmic billiards. Today, scars from such ancient blows are no longer found. Some of the trillions of debris flying through space coalesced into the protoplanet Theia. The orbit that brought her to a collision with the Earth. The impact on the young Earth was a sliding one. The cores of the planets merged together, and huge masses of molten rock were thrown into low Earth orbit. Since this substance was liquid, it easily gathered into a spherical object, which became the Moon.
Although the mass of the Moon is 27 million times less than the mass of the Sun, it is 374 times closer to the Earth and exerts strong influence, causing rising waters (tides) in some places and low tides in others. This happens every 12 hours and 25 minutes, since the Moon makes a complete revolution around the Earth in 24 hours and 50 minutes.
The Moon is the companion of the Earth in outer space. Every month, the Moon makes a complete journey around the Earth. It glows only by light reflected from the Sun.
The Moon is Earth's only satellite and the only extraterrestrial world that humans have visited. By studying it, a person learned to use its properties for his own needs, without causing harm. environment.
1 Origin of the Moon
The origin of the moon has not yet been definitively established. The problem is that we have too many assumptions and too few facts. All this happened so long ago that none of the hypotheses can be tested.
Theories in different time a lot has been suggested. Three mutually exclusive hypotheses were considered the most probable. One is the capture hypothesis, according to which the Moon formed independently of the Earth and was later captured by its gravitational field. Another is the co-formation hypothesis, according to which the Earth and the Moon formed from a single gas and dust cloud. And the third is the hypothesis of centrifugal separation, according to which the Moon broke away from the Earth under the action of centrifugal forces.
However, an analysis of the samples of lunar soil delivered by American astronauts cast all these hypotheses into doubt. Scientists had to put forward a new one - the collision hypothesis, according to which the Moon was formed as a result of the collision of the protoplanet Earth with another large cosmic body - the protoplanet Theia.
Giant Impact Hypothesis
Figure 1 - The collision of the Earth with Theia
The collision hypothesis was proposed by William Hartman
The collision hypothesis is currently considered the main one, since it explains well all known facts about chemical composition and the structure of the Moon, as well as the physical parameters of the Earth-Moon system. Initially, the possibility of such a successful collision (oblique impact, low relative velocity) of such a large body with the Earth caused great doubts. But then it was assumed that Theia was formed in the orbit of the Earth, at one of the Lagrange points
To explain the iron deficiency on the Moon, one has to assume that by the time of the collision (4.5 billion years ago), gravitational differentiation had already occurred both on Earth and on Teia, that is, a heavy iron core was released and a light silicate mantle was formed. Unambiguous geological confirmation of this assumption was not found.
If the Moon somehow ended up in the orbit of the Earth at such a distant time and after that did not undergo significant shocks, then, according to calculations, a multi-meter layer of dust settling from space would allegedly have accumulated on its surface
2 Movement of the Moon
The moon moves around the earth average speed 1.02 km / s in an approximately elliptical orbit in the same direction as the vast majority of other bodies in the solar system, that is, counterclockwise, sat down to look at the moon's orbit from the side North Pole peace. The semi-major axis of the Moon's orbit, equal to the average distance between the centers of the Earth and the Moon, is 384,400 km (approximately 60 Earth radii). Due to the ellipticity of the orbit and perturbations, the distance to the Moon fluctuates between 356,400 and 406,800 km. The period of revolution of the Moon around the Earth, the so-called sidereal (stellar) month, is 27.32166 days, but is subject to slight fluctuations and a very small secular reduction. The motion of the Moon around the Earth is very complex, and its study is one of the the most difficult tasks celestial mechanics.
Elliptical motion is only a rough approximation and is superimposed by many perturbations due to the attraction of the Sun, planets, and the oblateness of the Earth. The most important of these perturbations, or inequalities, were discovered from observations long before their theoretical derivation from the law of universal gravitation. The attraction of the Moon by the Sun is 2.2 times stronger than by the Earth, so that, strictly speaking, one should consider the movement of the Moon around the Sun and the perturbations of this movement by the Earth. However, since the researcher is interested in the motion of the Moon as seen from the Earth, the gravitational theory, which was developed by many leading scientists, starting with I. Newton, considers the motion of the Moon precisely around the Earth. In the 20th century, the theory of the American mathematician J. Hill is used, on the basis of which the American astronomer E. Brown calculated (1919) mathematical series and compiled tables containing the latitude, longitude and parallax of the Moon. The argument is time.
The plane of the Moon's orbit is inclined to the ecliptic at an angle of 5o843, subject to slight fluctuations. The points of intersection of the orbit with the ecliptic, called the ascending and descending nodes, have uneven backward movement and make a complete revolution along the ecliptic in 6794 days (about 18 years), as a result of which the Moon returns to the same node after a time interval - the so-called draconic month, - shorter than sidereal and on average equal to 27.21222 days, the periodicity of solar and lunar eclipses. The moon rotates around an axis inclined to the plane of the ecliptic at an angle of 88 ° 28 ", with a period exactly equal to the sidereal month, as a result of which it is always turned to the Earth by the same side.
Such a coincidence of the periods of axial rotation and orbital revolution is not accidental, but is caused by the friction of the tides, which the Earth produced in the solid or once liquid shell of the Moon. However, the combination of uniform rotation with uneven movement along the orbit causes small periodic deviations from a constant direction to the Earth, reaching 7 ° 54 "in longitude, and the inclination of the axis of rotation of the Moon to the plane of its orbit causes deviations of up to 6 ° 50" in latitude, as a result of which in different time from the Earth can be seen up to 59% of the entire surface of the Moon (although the areas near the edges of the lunar disk are visible only in a strong perspective); such deviations are called the libration of the moon. The planes of the equator of the Moon, the ecliptic and the lunar orbit always intersect in one straight line (Cassini's law).
1.3 Shape of the Moon
The shape of the Moon is very close to a sphere with a radius of 1737 km, which is equal to 0.2724 of the Earth's equatorial radius. The surface area of the moon is 3.8 * 107 km2, and the volume is 2.2 * 1025cm3. A more detailed determination of the figure of the Moon is difficult because on the Moon, due to the absence of oceans, there is no clearly expressed level surface in relation to which heights and depths could be determined; in addition, since the Moon is turned to the Earth on one side, it seems possible to measure from the Earth the radii of points on the surface of the visible hemisphere of the Moon (except for points on the very edge of the lunar disk) only on the basis of a weak stereoscopic effect due to libration.
The study of libration made it possible to estimate the difference between the principal semiaxes of the Moon's ellipsoid. The polar axis is less than the equatorial one, directed towards the Earth, by about 700 m and less than the equatorial axis, perpendicular to the direction of the Earth, by 400 m. Thus, the Moon, under the influence of tidal forces, is slightly elongated towards the Earth. The mass of the moon is most accurately determined from observations of its artificial satellites. It is 81 times less than the mass of the earth, which corresponds to 7.35 * 1025g. The average density of the Moon is 3.34 g cm3 (0.61 of the average density of the Earth). The acceleration of gravity on the surface of the Moon is 6 times greater than on the Earth, is 162.3 cm.sec2 and decreases by 0.187 cm.sec2 when ascending 1 kilometer. First space velocity 1680 m.sec, second 2375 m.sec. Due to the small attraction, the Moon could not keep a gaseous shell around it, as well as water in a free state.
1.4 Moon phases
The change in the phase of the Moon is due to changes in the conditions of illumination by the Sun of the dark ball of the Moon as it moves in orbit. With change relative position Earth, Moon and Sun, the terminator (the boundary between the illuminated and unilluminated parts of the Moon's disk) moves, which causes a change in the outlines of the visible part of the Moon.
The duration of a complete change in the phases of the moon (the so-called synodic month) is not constant due to the ellipticity of the lunar orbit, and varies from 29.25 to 29.83 Earth solar days. The average synodic month is 29.5305882 days (29 days 12 hours 44 minutes 2.82 seconds).
In the phases of the moon close to the new moon (at the beginning of the first quarter and at the end of the last quarter), with a very narrow crescent, the unlit part forms the so-called. the ashen light of the moon is the visible glow of the unlit direct sunlight surfaces of a characteristic ash color.
The moon goes through the following phases of illumination:
.new moon - a state when the moon is not visible.
.the young moon is the first appearance of the moon in the sky after the new moon in the form of a narrow sickle.
.the first quarter is the state when half of the moon is illuminated.
.waxing moon
.full moon - a state when the entire moon is lit.
Waning moon
.last quarter - a state when half of the moon is again illuminated.
old moon
1.5 Internal structure of the Moon
Figure 2 - the internal structure of the moon
The Moon, like the Earth, consists of distinct layers: crust, mantle and core. Such a structure is believed to have formed immediately after the formation of the Moon - 4.5 billion years ago. The thickness of the lunar crust is believed to be 50 km. Moonquakes occur in the thickness of the lunar mantle, but unlike earthquakes, which are caused by the movement of tectonic plates, moonquakes are caused by the tidal forces of the Earth. The core of the moon, like the earth's core, is made of iron, but its size is much smaller and is 350 km in radius. The average density of the Moon is 3.3 g/cm3.
STATEMENT OF THE RESEARCH PROBLEM
To achieve this goal, it is necessary to solve the following tasks:
to study the Moon and its influence on the Earth;
compare the forces and processes that affect the Earth under the influence of the Moon and other planets;
to analyze earthquakes connected by the Moon with the planet Earth;
In the future, work will continue on the topic "Influence of the Moon as a natural satellite on the planet Earth" with the study of the active phenomena of the Moon. An analysis of the received data will be carried out, according to the results that we will receive in the process of calculating and studying the interaction of the satellite with the planet.
2. RESEARCH METHOD
1 Ebb and flow
The influence of the Moon on the earthly world exists, but it is not pronounced. It is almost impossible to see it. The only phenomenon that visibly demonstrates the effect of the moon's gravity is the effect of the moon on the tides. Our ancient ancestors associated them with the Moon. And they were absolutely right. The tides are so strong in some places that the water recedes hundreds of meters from the coast, exposing the bottom, where the peoples living on the coast collected seafood. But with inexorable precision, the water receding from the shore rolls again. If you do not know how often the tides occur, you can be far from the coast and even die under the advancing water mass. The coastal peoples perfectly knew the timetable for the arrival and departure of the waters. This phenomenon occurs twice a day. Moreover, ebbs and flows exist not only in the seas and oceans. All water sources are influenced by the moon. But far from the seas, this is almost imperceptible: sometimes the water rises a little, then it falls a little. Fluid is the only natural element that moves behind the moon, making oscillations. A stone or a house cannot be attracted to the moon because they have a solid structure. The malleable and plastic water clearly demonstrates the effect of the lunar mass.
The Moon most strongly affects the waters of the seas and oceans from that side of the Earth, which at the moment is directly facing it. If you look at the Earth at this moment, you can see how the Moon draws the waters of the oceans towards itself, lifts them, and the water column swells, forming a “hump”, or rather, two “humps” appear - high from the side where the Moon is located , and less pronounced on the opposite side. "Humps" precisely follow the movement of the Moon around the Earth. Since the world ocean is a single whole and the waters in it communicate, the humps move from the coast, then to the coast. Since the Moon passes twice through points located at a distance of 180 degrees from each other, we observe two high tides and two low tides.
The greatest ebb and flow occur on the ocean shores. In our country - on the shores of the Arctic and Pacific Oceans. Less significant ebbs and flows are typical for inland seas. Even weaker this phenomenon is observed in lakes or rivers. But even on the shores of the oceans, the tides are stronger at one time of the year and weaker at another. This is already connected with the remoteness of the Moon from the Earth. The closer the Moon is to the surface of our planet, the stronger the ebbs and flows will be. The further - the, naturally, weaker. Water masses are influenced not only by the Moon, but also by the Sun. Only the distance from the Earth to the Sun is much greater, so we do not notice its gravitational activity. But it has long been known that sometimes the tides become very strong. This happens whenever there is a new moon or a full moon. This is where the power of the Sun comes into play. At this moment, all three planets - the Moon, the Earth and the Sun - line up in a straight line. Two forces of attraction already act on the Earth - both the Moon and the Sun. Naturally, the height of the rise and fall of the waters increases. The strongest will be the combined influence of the Moon and the Sun, when both planets are on the same side of the Earth, that is, when the Moon is between the Earth and the Sun. And more water will rise from the side of the Earth facing the moon.
In relation to the planet Earth, the cause of tides is the presence of the planet in the gravitational field created by the Sun and the Moon. Since the effects they create are independent, the impact of these celestial bodies on the Earth can be considered separately. In this case, for each pair of bodies, we can assume that each of them revolves around a common center of gravity. For the Earth-Sun pair, this center is located in the depths of the Sun at a distance of 451 km from its center. For the Earth-Moon pair, it is located deep in the Earth at a distance of 2/3 of its radius.
Each of these bodies experiences the action of tidal forces, the source of which is the gravitational force and internal forces that ensure the integrity of the celestial body, in the role of which is the force of its own attraction, hereinafter referred to as self-gravity. The emergence of tidal forces is most clearly seen in the example of the Earth-Sun system.
The tidal force is the result of the competing interaction of the gravitational force directed towards the center of gravity and decreasing inversely with the square of the distance from it, and the fictitious centrifugal force of inertia due to the rotation of a celestial body around this center. These forces, being opposite in direction, coincide in magnitude only at the center of mass of each of the celestial bodies. Due to the action of internal forces, the Earth revolves around the center of the Sun as a whole with a constant angular velocity for each element of its mass. Therefore, as this element of mass moves away from the center of gravity, the centrifugal force acting on it grows in proportion to the square of the distance. A more detailed distribution of tidal forces in their projection onto a plane perpendicular to the plane of the ecliptic is shown in (Fig. 3).
Figure 3 is a diagram of the distribution of tidal forces in projection onto a plane perpendicular to the Ecliptic. A gravitating body is either on the right or on the left.
The reproduction of changes in the shape of bodies subjected to their action, achieved as a result of the action of tidal forces, can, in accordance with the Newtonian paradigm, be achieved only if these forces are fully compensated by other forces, which may include the force gravity.
Figure 4 - deformation of the Earth's water shell as a result of the balance of tidal force, self-gravity force and the force of water reaction to the compressive force
As a result of the addition of these forces and arise symmetrically on both sides the globe tidal forces directed in different directions from it. The tidal force directed towards the Sun is of a gravitational nature, while that directed away from the Sun is a consequence of a fictitious inertial force.
These forces are extremely weak and cannot be compared with the forces of self-gravity (the acceleration they create is 10 million times less than the acceleration of free fall). However, they cause a shift of the particles of water in the oceans (resistance to shear in water at low speeds is practically zero, while compression is extremely high), until the tangent to the surface of the water becomes perpendicular to the resulting force.
As a result, a wave arises on the surface of the World Ocean, which occupies a constant position in systems of mutually gravitating bodies, but runs along the surface of the ocean together with the daily movement of its bottom and coasts. Thus (neglecting ocean currents) each particle of water makes an oscillatory movement up and down twice during the day.
The horizontal movement of water is observed only near the coast as a result of the rise in its level. The speed of movement is greater, the more gently the seabed is located.
Tidal phenomena occur not only in the water, but also in the air shell of the Earth. They are called atmospheric tides. Tides also occur in the solid body of the Earth, since the Earth is not absolutely solid. Vertical oscillations of the Earth's surface due to tides reach several tens of centimeters.
2 Earthquakes and the Moon
moon phase tide
The moon can cause not only tides on Earth, but is also the cause of earthquakes. The approach of a satellite of the Earth every day raises the surface of our planet by 30 cm. Large earthquakes are not so dependent on the influence of the Moon, since they occur on rock shifts at great depths under great stress. In any case, the lunar effect is much weaker than it seems. Tectonic plates have been accumulating tension for centuries. If earthquakes were directly related to lunar tides , then they would occur every day when the attraction of the satellite would reach a maximum.
The earthquake is explained by the presence of gravitational links between the Earth and the Moon, the tides of their solid crust, and the mutual rotation of bodies. If we take into account that vibrations of the solid crust occur elastically, at certain points in time, due to the presence of defects in the solid crust, in faults, “bounce” peaks arise - similar to the “bounce” of a metal rod. If we have a metal rod without defects and excite mechanical vibrations in it, we will observe the vibrations that we have excited at each of its points. If there are defects in this rod, the crack "bounce" that occurs in the crack will be superimposed on the sinusoidal vibrations. At that moment, when the wave carrying the “bounce” from all sides comes to the corresponding crack, energy will be released at the location of the crack.
A similar picture of the development of an earthquake in the earth's crust. The undamped oscillations of the earth's crust are created by the rotation of the earth and the gravitational forces of the moon, the sun and pass elastically along the surface of the earth. The bounce occurs in places of "live cracks", where the oscillations of the tidal wave in the Earth are not transferred smoothly, elastically, but displacements occur. The direction of the gravitational force between the Earth and the Moon determines the direction of the communication line of the bounce wave from the Earth to the Moon (to the Sun). During the existence and development of the gravitational connection, two main forces act on the rocks of the Earth. This is the gravitational force of the Earth and the gravitational force of the Moon. When the Moon leaves and the connection is broken, only the attraction of the Earth remains. The entire difference between the energies of the attraction of the Earth and the Moon is directed to the location of the future epicenter of the earthquake. At the moment of "rupture" of this connection during the rotation of the planets, a wave appears, directed to the place of origin of the bounce. In this wave, called the "KaY" wave, it is characteristic that it arises due to the emergence of a gravitational resonant connection of "rattling zones" on the Moon and Earth. When the Moon moves, this communication line shifts, with the balance of the gravitational forces of the planets. When communication with the Moon is lost, the line breaks and reverse "KaY" waves ("Kay" - Kozyrev and Yagodin) appear on the Earth and on the Moon, carrying energy towards future earthquake epicenters. Since this wave goes to one point from the area, its energy increases and by the time it arrives at the point it has tremendous energy, causing an earthquake in that place. Very often you can observe how "bounce" occurs on a wave and is detected by the sensor in the form of a "group of peaks". They correspond not to one earthquake, but to a whole group of earthquakes over a large area at different times. In this case, each peak corresponds to a shock in these earthquakes, and the quotient of dividing the distance from the sensor to the epicenters of these earthquakes by the time elapsed from the appearance of the peak on the sensor to the start of the corresponding earthquakes is a constant.
3. RESULTS OF THE STUDY
The purpose of this work was to calculate the gradient of the force of the Moon with which it acts on the planet Earth (comparable to the Sun):
The force of gravitational attraction is proportional to the mass M of the attracting body and inversely proportional to the square of the distance R to it. Accordingly, on the surface of the Earth, the force of attraction to the Earth itself (M Earth = 6 1027 g. R Earth = 6378 km) is 1 g, to the Sun (M Sun = 2 1033 g. R Sun = 150 106 km) - 0.00058 g, and to the Moon (M of the Moon = 7 1025 of the Moon = 384 103 km) - only 0.0000031g, i.e. 190 times weaker than to the Sun. It is also obvious that there will be no tides in a uniform force field.
However, the gravitational field is not homogeneous, but has a center in the attracting mass M. Accordingly, for any body with finite dimensions, there will be a difference in gravitational forces at opposite edges, which is called the tidal force. The tidal force will be proportional to the first derivative of the gravitational force. The force of gravity is inversely proportional to the square of the distance, and the derivative of 1/r2 is -2/r3, that is, inversely proportional to the cube of the distances.
Therefore, the Moon, which is much closer to the Earth, despite its small mass, creates a tidal force almost 2 times greater than that of the Sun.
And you also need to explain why there are no earthquakes at the poles.
Earthquakes occur at the junction lithospheric plates. Plate boundaries correspond to ocean shelves on geographical maps. There are no tectonic plates at the north pole, there is one at the south pole, but it is not moving anywhere. We found out that the Moon does not create earthquakes itself, directly, therefore, there are no earthquakes at the poles. Of course, tidal forces do not act at the poles.
Figure 5 - location of lithospheric plates
The Earth and the Moon revolve around the common center of gravity (barycenter) of the system Earth - Moon with a sidereal (relative to the stars) period of 27.3 days (days). The Earth describes an orbit that is a mirror image of the Moon's orbit, but its dimensions are 81 times smaller than the lunar orbit. The barycenter is always located inside the Earth, at a distance of about 4670 km from its center. The body of the Earth revolves without rotation (translationally) around the “fixed” (in the Earth-Moon system) barycenter. As a result of such a monthly rotation of the Earth, all terrestrial particles are affected by exactly the same centrifugal force as in the center of mass of the Earth. The sum of the vectors of the centrifugal force and the gravitational force of the moon is called the tidal force of the moon. The tidal force of the Sun is determined similarly. The magnitude of the tidal force is a function of the declination and geocentric distance of the Moon (or Sun). The amplitude of the monthly fluctuations in the declination of the Moon changes with a period of 18.61 years from 29° to 18°, due to the precession of the axis (regression of nodes) of the lunar orbit. The perigee of the lunar orbit moves with a period of 8.85 g. The declination and geocentric distance of the Sun change with a period of 1 year. The earth revolves around own axis with a daily period. As a result, the amplitude of fluctuations of lunisolar tidal forces changes in time with periods: 18.61 years, 8.85 years, 6.0 years, 1 year, 0.5 years, monthly, semi-monthly, weekly, daily , semidiurnal and many other less significant periods.
Statistics of the most dangerous earthquakes and tsunamis from 1960 - 2011
The Great Chilean Earthquake is probably the most strong earthquake in the history of observation, magnitude - from 9.3 to 9.5, occurred on May 22, 1960 at 19:11 UTC.
Location of the epicenter - 39°30? Yu. sh. 74°30? h. d.
Moon: phase 6% before new moon, distance 396679 km; astronomical new moon on May 25, 1960 12:27, the distance from the center of the Earth to the center of the moon is 403567 km, but before that the full moon on May 11, 1960 05:41 UTC, 362311 km, is a supermoon.
The strength of the earthquake (by moment) -9.2.
Earthquake strength (by surface waves) - 8.4
Latitude 61° 2" 24" N Longitude 147° 43" 48" W
Moon: phase 0% - full moon, distance 393010 km.
Tashkent earthquake on April 26, 1966 at 5:23 am. - catastrophic earthquake (magnitude 5.2).
Latitude. 41° 12" 0" N Longitude. 69° 6" 0" E
Moon: phase 27%, distance 371345 km;
The Tangshan earthquake on July 28, 1976 at 3:42 local time (July 27, 1976 19:48 UTC) is a catastrophic earthquake with a magnitude of 8.2.
Latitude 39° 39" 50" N Longitude 118° 24" 4" E
Moon: phase 1% - new moon, distance 376365 km.
Spitak earthquake December 7, 1988 at 10:41 MCK (7:41 UTC) a catastrophic earthquake of magnitude 7.2.
Latitude. 40° 59" 13" N Longitude. 44° 11" 6" E
Moon: phase 4% BC (2 days), distance 394161 km;
Earthquake in Kobe. The earthquake occurred on the morning of Tuesday January 17, 1995 at 05:46 local time (January 16, 1995 20:46 UTC). The force of the shocks reached 7.3 magnitudes on the Richter scale.
84° north latitude and 143.08° east longitude.
Moon: 100% phase - full moon, distance 395878 km, previous new moon January 1, 1995 10:55 UTC, distance to the Moon 362357 km. Supermoon.
The earthquake in Neftegorsk - an earthquake with tragic consequences of magnitude 7.6 on the Richter scale, occurred on the night of May 28, 1995 at 1:03 (May 27, 1995 13:03 UTC).
The epicenter is 55° north latitude and 142° east longitude.
Moon: phase 3% before new moon, distance 402328 (new moon - May 29, 1995 09:28), but before that: full moon May 14, 1995 20:47 UTC, distance 358563 km. Supermoon.
The Izmit earthquake is a catastrophic earthquake (magnitude 7.6) that occurred on August 17, 1999 in Turkey at 03:01 local time (UTC 00:01:39).
Latitude 40° 44" 53" N Longitude 29° 51" 50" E
Moon: 30% phase after new moon (5 days), distance 400765 km;
The Sichuan earthquake is a devastating 7.9 magnitude earthquake that occurred on May 12, 2008 at 14:28:01 local time (06:28:01 UTC) in China.
Latitude 31° 0" 7" N Longitude 103° 19" 19" E
Moon: 51% phase, 7 days after new moon, distance 379,372 km: new moon May 5, 2008 10:55 UTC, distance to the Moon 358,184 km. Supermoon.
Earthquake and tsunami in the Indian Ocean December 26, 2004 at 00:58 UTC - the second most powerful earthquake in the history of observations (magnitude 9.2) and the deadliest of all known tsunamis.
30° north latitude and 95° 87" east longitude.
Moon: phase 100%, full moon 404408 km, but before that new moon 12 December 01:28, 364922 km. Supermoon.
April 2, 2007 tsunami, Solomon Islands (archipelago). Caused by a magnitude 8 earthquake in the southern part of Pacific Ocean at 07:39. Waves several meters high reached New Guinea.
Moon: phase 0%, full moon, distance 404000 km, previous new moon March 19, 2007 at 02:44, 364311 km. Supermoon.
Earthquake and tsunami Japan, Honshu, 9.0, occurred on March 11, 2011 at 14:46 local time (05:46 UTC). Latitude 38.30N and longitude 142.50E. The earthquake source was located at a depth of 32 km.
Moon: 32% phase after new moon (5 days), distance 393837. Astronomical new moon March 4, 2011 20:47, distance 404793 km; but the nearest full moon is March 19, 2011 20:46. Supermoon.
Above are catastrophic earthquakes and tsunamis over the past 50 years. The statistics show that all of them happened during the full moon or new moon (with the exception of Tashkent and Izmit, which indirectly indicates their technogenic nature). In addition, almost 80% of them are related to the supermoon in one way or another. Based on this analysis, we can conclude that during the periods of supermoons, the danger of disasters from natural elements really increases.
Figure 6 - diagram of the distribution of earthquakes depending on the phases of the moon and its position in orbit
When constructing the diagram, we completely abstracted from all the inequalities of the motion of the Moon. The mean values of the synodic (29.5 days) and anomalistic months (27.5 days) were taken. The diagram shows the average positions of syzygies and quadratures, and the apogee (A) is shown as the average moment between adjacent perigees (P). For each earthquake, its distance in time to the nearest, marked on the diagram, phase of the Moon and to the moment of the passage of the Moon through perigee or apogee was determined. The construction uncertainty arising from the simplifications made hardly reaches one day. On the constructed diagram, each earthquake is marked with a dot. Earthquakes that hit the frame of the diagram are marked next to it, inside the diagram, and repeated at each of the opposite sides of the frame.
The constructed diagram clearly shows that near the perigee, earthquakes most often occur in syzygies, i.e. at full moon and new moon, and at that time there are almost no near quadratures. The second well-defined feature of the diagram is the grouping of earthquakes along the directions going at an angle of 45 degrees. from syzygies to perigee. These directions represent the sequence of days of those lunations in which the new moon or full moon coincided with perigee. Consequently, favorable for earthquakes are not only the days of maximum tides of the earth's crust, but also the days immediately following them. Thus, the maximum tides disturb the state of the outer layers of the Earth to such an extent that for a time of about a month, conditions favorable for earthquakes persist.
CONCLUSION
In the course of this work, the natural satellite of the planet Earth - the Moon was studied.
The effects of the Moon on the Earth have been studied.
According to this observation, we can conclude that the Moon really has its effect on the planet Earth, both favorable and not. If we consider the influence of the phases of the moon on a person, there is an assumption that it can also improve or worsen his well-being and thereby influence his activities. The study of the satellite and its impact is not yet fully understood. However, man has already learned to use such property as gravitational force. A tidal power plant is a special type of hydroelectric power plant that uses the energy of the tides, and in fact kinetic energy rotation of the earth. Tidal power plants are built on the shores of the seas, where the gravitational forces of the Moon and the Sun change the water level twice a day. Water level fluctuations near the coast can reach 18 meters. Tidal hydroelectric power plants are considered the most environmentally friendly. Therefore, the study of this topic has a huge role. That is why I consider the chosen topic quite relevant.
LIST OF SOURCES USED
Frish S. A., Timoreva A. V. // Course general physics, Textbook for physics and mathematics and physics and technology faculties public universities 1957. Vol. 1, issue. 2. S. 312
Belonuchkin V. // Tidal forces Kvant. 1989. Vol. 12, no. 3. S. 435.
Markov A. Road to the Moon // In the journal. "Aviation and Astronautics". ? 2002.? No. 3. - S. 34.
General course of astronomy / Kononovich E.V., Moroz V.I.
E ed., Rev. - M.: Editorial URSS, 2004. - 544 p.
Ranzini D.M. // Space, 2002. - S. 320.
Stars and planets. / Ya.M. Ridpath / Atlas of the Starry Sky,
V.D. Krotikov, V.S. Trinity. Radio emission and the nature of the Moon // Uspekhi fizich. Nauk, 1963. V.81. Issue 4. p.589-639
A.V. Khabakov. On the main questions of the history of the development of the lunar surface. M, 1949, 195 p.
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The phases of the moon are different and not quite so connected. Ebb and flow is a phenomenon of daily periodicity. The phases of the moon are a phenomenon with a frequency of 29.5 days per lunar month.
The phases of the moon are how the Earth casts a shadow illuminated by the Sun on the Moon. The moon revolves around the earth, the position of the moon, the earth and the sun changes, and the shadow on the moon from the earth also changes.
Imagine two balls. They are connected by a bar. A large ball rotates around its axis. And that small ball that is on the other end of the bar revolves around the big ball. The bar is an image of the force of attraction between the Earth and the Moon. In the place where the rod is fixed, tidal disturbances are obtained.
If the Earth did NOT rotate around its axis, then the tide would follow the surface of the Earth behind the Moon, which revolves around the Earth with a period of ~ 27 days (why not 29.5 is a separate question - google the difference between sidereal and synodic months).
But we also have the rotation of the Earth around its axis.
That is, returning to the image of the connecting rod. In the case of the Earth and the Moon, the rod is rigidly fixed on the Moon, that is, the Moon faces the Earth on one side (it only "sways" a little), but on the Earth the rod is not fixed, but moves along the surface. The earth rotates on its axis with a period of 24 hours.
Those. the tidal hump runs no longer with a period of ~27 days, but with a period of 24 hours.
But it needs to be clarified. In fact, the ebbs and flows, only for simplicity, are explained by the Moon alone, but in fact:
Also, one of the reasons for the occurrence of tides is the daily (proper) rotation of the Earth. The masses of water in the oceans, having the shape of an ellipsoid, the major axis of which does not coincide with the axis of rotation of the Earth, participate in its rotation around this axis. This leads to the fact that in the reference frame associated with the earth's surface, the ocean runs along mutually opposite sides of the globe, two waves, leading at every point of the ocean coast to periodic, twice a day, recurring phenomena of low tide, alternating with high tides.
The most interesting thing, pay attention (last sentence), in one hemisphere there is a tide and the opposite is also a tide. Those. the water shell is like an ellipsoid, not like a pear.
Over time, we formed a double question and in it you can read additionally about how an ellipsoid is obtained instead of a pear. See the comments on the answer.
It is also important to say about the influence of the sun on the tides using the example of syzygy and quadrature tides. Sometimes the sun, moon and earth line up (earth<--луна<--солнце) и силы притяжения солнца и луны - складываются, соответственно самые сильные приливы - сизигийные. Они происходят во время новолуния и полнолуния. Квадратурные приливы - самые слабые,когда силы тяготения луны и солнца находятся под прямым углом и частично нейтрализуют друг друга. Они происходят, когда луна находится в фазе первой четверти и последней четверти. Также можно почитать о приливах здесь astro-site.narod.ru/zemlimsiz.html
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