Even at school, they drive us into the following picture of the world. Earth is a spherical planet orbiting in space around a star called the Sun. The earth rotates on its axis. This axis is inclined to the ecliptic plane at an angle of 23.44 degrees. This slope allows the seasons to change. The very tilt of the Earth was allegedly formed because a celestial body hit our planet. Every student knows this data.
Scientists in their scientific constructions also dance from them. Nobody checks the correctness of such statements. But I checked. And it turned out that everything that is suggested to us at school is a sick delirium, in which there is not a grain of truth.
So, let's start with the impact of a celestial body. Let's not argue about the fact that first you need to prove that the cosmos exists. After all, this concept itself initially did not mean interstellar space at all. Cosmos was the personal name for Earth in Greek, and it signified the order and beauty of our "planet."
It is impossible to prove the existence of space today, for while humanity does not even have an understanding of what this could be. But the impact on the Earth with a certain celestial body, we can look at the experience. The same astronauts, who are in zero gravity, have repeatedly demonstrated their experience with a gyroscope, striking it with a hammer. After the impact, the gyroscope axis never changed its direction.
The ground in the official version is a gyroscope. No impact can change the axis of such a rotating body. Thus, it is necessary to look for another explanation for the change in the slope of the soybean. If, of course, such a change ever took place. Let's remember that scientists tell us that the change in the axis tilt supposedly took place many millions of years ago. But this is an outright lie.
Let's remember the school course on orientation on the ground. South is towards the summer solstice, north is towards the winter solstice. East - in the direction of the vernal equinox, and west - in the autumn. These directions are reflected in the calendar. And here we find a solution to the so-called tilt of the earth's axis.
There is a well-known and publicly available geographic map. It is dated 1452. That is, the time when the Julian calendar was used throughout the world, and before the invention of the Gregorian calendar, there were almost one and a half hundred years. So on this map, the direction to the East corresponds to the date of March 1. This calendar is superimposed directly on the map, so no other interpretation is required. Everything is very simple.
That is, in the 15th century, the direction to the East, that is, on the day of the vernal equinox, was exactly on March 1. And today, the day of the vernal equinox is shifted to the date of March 22. All other equinox and solstice dates are similarly shifted. There is a feeling that the calendar has turned 22 days, and now the days of equinoxes and solstices occur later by 22 days. That is, according to physicists, the tilt of the Earth's axis happened in the 15th century? It was at this time that a certain cosmic body allegedly hit the Earth! But historians have not recorded this. And we understand that such an explanation for the change in the tilt of the Earth's axis is outright delirium.
But back to 22 days. For such a number of days, the calendar is late in our time, and in the 18th - 19th centuries, these days fell on the night from the 23rd to the 24th. We know about this not only from the astronomical tables of those centuries, but also from traditional holidays. Kupalo was celebrated from 23 to 24 June, Karachun - from 23 to 24 December, Komoeditsa - from 23 to 24 March. That is, the real shift of the calendar took place not by 22 days, but by 23.5 days. And this figure surprisingly coincides with the angle of inclination of the axis of the earth.
I will not talk about the precession of the Earth's axis, since it is also an invention. I'll tell you right away why these 23.5 days of the calendar shift appeared. During the use of the Julian calendar, the Earth was the center of the world, and the Sun revolved around it. People perceived the Sun as a mechanism for counting time. The fact that this is so allows us to understand the same Bible, which says that God created the moon and the sun not for illumination, but for timing. A sundial was built on the movement of the sun. Their design was very different from that of modern clocks. And in the same way, the Julian calendar was different from the Gregorian calendar.
In modern watches, the dial is round, the hand is attached to the center of the dial, and the numbers themselves are evenly spaced around the circumference. This is also the model for the Gregorian calendar. In the Julian calendar, the dial was shaped in a different way - like a sundial. The point of attachment of the arrow was on a circle, and the working area was 270 degrees. That is, not a full circle, but three quarters of a circle.
These 270 degrees were called day and were divided into 12 parts. Each was called - "hour", that is, a part. There was an average of 22.5 degrees per hour. In the Julian calendar, the night was not taken into account, since there were no stars in the sky. The quarter circle was simply not used. When the Gregorian calendar replaced the Julian calendar, the new reckoning of time began to use the entire circle, so the unused quarter of the time circle was simply added arithmetically to the angular value of the Julian hour.
It turned out that about 23 days were added each season. Therefore, the calendar has shifted to this value. No axis of the Earth tilted anywhere. In reality, the axis of the sundial has shifted from the periphery to the center. This was perceived as an axis tilt. And as a result, the calendar was 23 days late.
Here is one more secret of the Earth solved ...
Andrey Tyunyaev,
chief editor of the newspaper "President"
The Earth's axis of our planet in the northern vector is directed to the point where the star of the second magnitude, called Polar, is located in the tail
During the day, this star outlines a small circle on the celestial sphere with a radius of about 50 arc minutes.
In ancient times, they knew about the tilt of the earth's axis
A long time ago, in the 2nd century BC. e., the astronomer Hipparchus discovered that this point is mobile in the starry sky and slowly moves towards the movement of the sun.
He calculated the speed of this movement at 1 ° per century. This discovery was called This move ahead, or the anticipation of the equinox. The exact value of this movement, constant precession, is 50 seconds per year. Based on this, the full ecliptic cycle will be approximately 26,000 years.
Accuracy is important to science
Let's go back to the question about the pole. Determining its exact position among the stars is one of the most important tasks of astrometry, which measures arcs and angles in the celestial sphere in order to determine planets, proper motions and distances to stars, as well as solving problems of practical astronomy that are important for geography, geodesy and navigation ...
You can find the position of the pole of the world using photography. Imagine a long-focus photographic camera made in the form of an astrograph, directed motionlessly to the region of the sky near the pole. In such a photograph, each star will describe a more or less long arc of a circle with a single common center, which will be the pole of the world - the point where the rotation of the earth's axis is directed.
A little about the angle of inclination of the Earth's axis
The plane of the celestial equator, being perpendicular to the earth's axis, also changes its position, which causes the movement of the points of intersection of the equator with the ecliptic. In turn, the attraction by the Moon of the equatorial displacement tends to rotate the Earth in such a way that its equatorial plane intersects the Moon. But in this case, these forces act not on but on the masses, which form the equatorial swelling of its ellipsoidal figure.
Imagine a ball inscribed in the earth's ellipsoid, which it touches at the poles. Such a ball is attracted by the Moon and the Sun by forces directed towards its center. For this reason, the earth's axis remains unchanged. This attraction, acting on the equatorial bulge, tends to rotate the Earth so that the equator and the object attracting it coincide, thereby creating an overturning moment.
The Sun moves away from the equator twice during the year to ± 23.5 °, and the Moon's distance from the equator reaches almost ± 28.5 ° during the month.
Children's toy spinning top reveals a little secret
If the Earth did not rotate, then it would tend to tilt, as if nodding, so that the equator kept track of the Sun and the Moon.
True, due to the huge mass and inertia of the Earth, such oscillations would be very insignificant, since the Earth would not have time to react to such a rapid change of directions. We are familiar with this phenomenon with the example of a baby top. tends to overturn the top, but the centripetal force protects it from falling. As a result, the axis moves, describing a conical shape. And the faster the movement, the narrower the figure. The earth's axis behaves in the same way. This is a kind of guarantor of its stable position in space.
The tilt of the Earth's axis affects the climate
The earth moves around the sun in an orbit that is almost circular. Observing the speed of stars located near the ecliptic represents that at any moment we are approaching some stars and moving away from their opposite ones in the sky at a speed of 29.5 kilometers per hour. The change of seasons is the result of that. There is an inclination of the earth's axis to the orbital plane and is about 66.5 degrees.
Due to its small elliptical orbit, the planet is slightly closer to the Sun in January than in July, but the difference in distance is not significant. Therefore, the influence on the receipt of heat from our star is hardly noticeable.
Scientists believe that the earth's axis is an unstable parameter of our planet. Studies show that the angle of inclination of the earth's axis in relation to the plane of its orbit in the past was different and changed periodically. According to the legends that have come down to us about the death of Phaethon, in the descriptions of Plato, there is a mention of a shift in the axis at this terrible time by 28 °. This catastrophe took place over ten thousand years ago.
Let's dream a little and change the angle of inclination of the Earth
The current angle of the earth's axis with respect to the orbital plane is 66.5 ° and ensures not so sharp fluctuations in winter-summer temperatures. For example, if this angle were about 45 °, what would happen at the latitude of Moscow (55.5 °)? In May, the sun under such conditions will reach its zenith (90 °) and shift to 100 ° (55.5 ° + 45 ° \u003d 100.5 °).
With such an intense movement of the Sun, the spring period would pass much faster, and in May it would reach a temperature peak, like at the equator at the maximum solstice. Then it would be slightly weakened, since the sun, passing the zenith, would go a little further. Then it came back, passing the zenith again. For two months, in July and May, there would be an unbearable heat, around 45-50 degrees Celsius.
Now let's consider what would happen to the winter, for example, in Moscow? After passing the second zenith, our star would have dropped in the month of December to 10 degrees (55.5 ° -45 ° \u003d 10.5 °) above the horizon. That is, with the approach of December, the sun would come out for a shorter period than it is now, rising slightly above the horizon. During this period, the sun would shine for 1-2 hours a day. Under such conditions, the night temperature will drop below -50 degrees Celsius.
Every version of evolution has a right to life
As we can see, for the climate on the planet, it is important at what angle the earth's axis is. This is a fundamental phenomenon in the mild climate and living conditions. Although, perhaps, under different conditions on the planet, evolution would have gone a slightly different path, creating new species of animals. And life would continue to exist in its other variety, and, perhaps, there would be a place for a “different” person in it.
The change of seasons, which makes us freeze now, is actually extremely important to life on Earth. The seasons are the most important mechanism for maintaining the general temperature regime on the planet. The reason for this phenomenon is the tilt of the Earth's axis of rotation to the plane of the ecliptic. Rene Geller, an associate, believes that astrobiology has not yet paid enough attention to this important fact when assessing the possible habitability of exoplanets.
"The tilt of the axis of rotation and the change of seasons are important points in considering the habitability of an exoplanet, and so far it is almost completely ignored," says Geller.
To fill this gap, Geller and his colleagues published two papers on the evolution of the planet's tilt axis under the influence of the gravitational field of the star and other planets. Their study showed that the tilt decreases over time, and this happens especially quickly for the planets in the habitable zones of red dwarfs, and it is these potentially habitable planets that are the most. The inclination of the axis of rotation of the exoplanet in such conditions falls so quickly that life simply does not have time to originate on such a planet. Gliese 581d, one of the most famous candidates for the existence of life, falls under this scenario.
However, there is some good news. For Earth-sized planets orbiting sun-like stars, the tilt takes billions of years to fall to dangerous levels. In such a situation is the planet Kepler-22b, the first Earth-like exoplanet in the habitat.
The tilt of the Earth's axis of rotation to the plane of the ecliptic is now about 23.5 degrees, but its evolution on a geological time scale is still unknown. In general, this tilt, as well as rotation around its own axis (change of day and night) lead to the fact that the difference between the maximum and minimum temperatures on Earth is about 111 degrees. An impressive drop, but what if the tilt of the Earth's axis was removed?
When the axis of rotation is tilted less than 5 degrees, the equatorial regions will always receive maximum heat. At the same time, the poles will receive almost nothing: the sun's rays will simply "slide" off the surface of the Earth, without heating it, while now the South Pole is turned towards the Sun. The result is a strong temperature gradient with latitude. In such conditions, everything depends on luck. The planet can lose all of its atmosphere due to its heating above the equator, as a result of which heated air will fly into space, overcoming gravity. If this does not happen, then in the middle latitudes there may be areas suitable for life.
The planet acquires an inclination of the axis of rotation during the formation of other objects under the influence of gravitational fields. Likewise, their gravitational field can lead to a loss of tilt. Geller's group simulated this process for Gliese 581d. The simulation took into account only the planet itself and its star. As the gravitational field of the star pulls the side closer to it more strongly, deforming tidal forces arise that change the shape of the planet. The resulting friction leads to damping of the planet's angular velocity and, as a result, to a decrease in its inclination. The Moon is responsible for similar processes on Earth.
"The moment arising from the action of tidal and gravitational forces tends to position the planet so that its axis of rotation is perpendicular to the line connecting the centers of mass," explains Geller.
The time it takes for a planet to lose tilt depends on the star. The fainter the star shines, the closer the planet must be to it in order to get into the habitable zone. For many stars, the planets must be shaved, not exceeding the orbit of Mercury in the solar system. But the closer the planet is to the star, the stronger gravity acts on it and, therefore, the faster it loses the tilt of the axis of rotation.
For a planet that has the size and mass of the Earth and is in the habitat of a star and has a mass of a quarter of the Sun, the tilt of the rotation axis disappears in less than 100 million years. It turns out that in order to maintain the axis of rotation for a long time, the conditions must be exactly those in which we live. The Earth is only able to maintain a noticeable tilt for a billion years if the star has a mass of at least 90% solar.
“We have found that Earth-like planets in light-star habitats lose their tilt over a time that is noticeably shorter than the evolutionary time for life on Earth,” says Geller.
The tilt of the super-earths' axes should also decrease rapidly if they orbit a red dwarf. Gliese 581d, a super-earth, revolves around a red dwarf with a mass of only 31% of the sun, and the age of the entire system is about 9 billion years - twice the age of the solar system. So this planet should have lost its tilt long ago.
In addition to the loss of the angle of inclination of the axis of rotation, tidal forces cause a gradual loss of angular velocity, as a result of which the planet turns out to be turned with one side to the star. This is even more detrimental to life.
For stars comparable to the Sun, the habitat lies much further. The earth is one example of such a situation. But besides the star, there are other factors that affect the tilt. The presence of the moon and other planets leads to the emergence of new gravitational forces. In the solar system, Jupiter should be wary of most, but we're in luck. The Moon saved the Earth from the influence of this huge planet, compensating for its gravitational influence.
But Mars was out of luck. Jupiter's influence can rotate this planet's axis of rotation 60 degrees in a million years. Such drastic changes in temperature and movement of glaciers would be fatal to life.
Geller's group has not yet carried out simulations taking into account other planets and moons due to the great computational complexity of the work. However, their model allows for this. However, an accurate calculation can wait. In any case, the current level of development of telescopes does not allow observing the rotation of exoplanets, so any theory regarding the tilt of the axis of rotation cannot be tested.
Our planet is constantly in motion:
- rotation around its own axis, movement around the sun;
- rotation with the Sun around the center of our galaxy;
- motion relative to the center of the Local Group of Galaxies, and others.
The movement of the earth around its own axis
Rotation of the Earth around its axis (fig. 1). An imaginary line around which it rotates is taken as the earth's axis. This axis is tilted 23 ° 27 "from the perpendicular to the plane of the ecliptic. The earth's axis intersects with the earth's surface at two points - the poles - North and South. When viewed from the North Pole, the Earth's rotation occurs counterclockwise or, as is commonly believed, with west to east The planet makes a complete revolution around its axis in one day.
Figure: 1. Rotation of the Earth around its axis
Day is a unit of time. There are stellar and sunny days.
Stellar day - this is the period of time during which the Earth turns on its axis in relation to the stars. They are equal to 23 hours 56 minutes 4 seconds.
Sunny day - this is the period of time during which the Earth turns around its axis in relation to the Sun.
The angle of rotation of our planet around its axis is the same at all latitudes. In one hour, each point on the Earth's surface moves 15 ° from its original position. But at the same time, the speed of movement is inversely proportional to the geographical latitude: at the equator it is equal to 464 m / s, and at a latitude of 65 ° it is only 195 m / s.
The rotation of the Earth around its axis in 1851 was proved in his experiment by J. Foucault. In Paris, in the Pantheon, a pendulum was hung under a dome, and a circle with divisions was hung under it. With each subsequent movement, the pendulum found itself on new divisions. This can only happen if the Earth's surface rotates under the pendulum. The position of the swinging plane of the pendulum at the equator does not change, because the plane coincides with the meridian. The axial rotation of the Earth has important geographic consequences.
When the Earth rotates, centrifugal force arises, which plays an important role in shaping the shape of the planet and reduces the force of gravity.
Another of the most important consequences of axial rotation is the formation of a rotational force - Coriolis forces. In the XIX century. it was first calculated by a French scientist in the field of mechanics G. Coriolis (1792-1843)... This is one of the forces of inertia introduced to take into account the effect of the rotation of a moving frame of reference on the relative motion of a material point. Its effect can be briefly expressed as follows: every moving body in the Northern Hemisphere deviates to the right, and in the Southern Hemisphere - to the left. At the equator, the Coriolis force is zero (Fig. 3).
Figure: 3. Action of the Coriolis force
The action of the Coriolis force extends to many phenomena of the geographic envelope. Its deflecting effect is especially noticeable in the direction of movement of air masses. Under the influence of the deflecting force of the Earth's rotation, the winds of the temperate latitudes of both hemispheres assume a predominantly westerly direction, and in tropical latitudes - easterly. A similar manifestation of the Coriolis force is found in the direction of movement of oceanic waters. The asymmetry of river valleys is also connected with this force (the right bank is usually high in the Northern Hemisphere, in the South - the left).
The rotation of the Earth around its axis also leads to the movement of solar illumination along the earth's surface from east to west, i.e., to the change of day and night.
The change of day and night creates a daily rhythm in living and inanimate nature. The daily rhythm is closely related to light and temperature conditions. The diurnal variation of temperature, day and night breezes, etc. are well known. Diurnal rhythms also occur in wildlife - photosynthesis is possible only during the day, most plants open their flowers at different hours; some animals are active during the day, others at night. Human life also runs in a daily rhythm.
Another consequence of the rotation of the Earth around its axis is the difference in time at different points on our planet.
Since 1884, the time zone was adopted, that is, the entire surface of the Earth was divided into 24 time zones, 15 ° each. Behind standard time take the local time of the middle meridian of each belt. Adjacent time zones differ by one hour. The boundaries of the belts are drawn taking into account the political, administrative and economic boundaries.
The zero belt is considered to be Greenwich (after the name of the Greenwich Observatory near London), which runs on both sides of the prime meridian. The time of the zero, or initial, meridian is considered World time.
Meridian 180 ° is accepted as international date line - a conditional line on the surface of the globe, on both sides of which hours and minutes coincide, and calendar dates differ by one day.
For a more rational use of daylight in the summer in 1930, our country introduced daylight saving time,leading the zone one by one hour. For this, the hands of the clock were moved forward one hour. In this regard, Moscow, being in the second time zone, lives according to the time of the third time zone.
Since 1981, in the period from April to October, the time has been moved forward one hour. This so called summer time. It is introduced to save energy. In summer, Moscow is two hours ahead of standard time.
The time of the time zone in which Moscow is located is moscow.
The movement of the earth around the sun
Rotating around its axis, the Earth simultaneously moves around the Sun, going around the circle in 365 days 5 hours 48 minutes 46 seconds. This period is called astronomical year. For convenience, it is assumed that there are 365 days in a year, and every four years, when out of six hours, 24 hours “accumulate”, there are not 365, but 366 days in a year. This year is called leap, and one day is added to February.
The path in space along which the Earth moves around the Sun is called orbit (fig. 4). The Earth's orbit is elliptical, so the distance from the Earth to the Sun is not constant. When the Earth is in perihelion (from the Greek. peri- near, near and helios- Sun) - the point of the orbit closest to the Sun - on January 3, the distance is 147 million km. It is winter in the Northern Hemisphere at this time. The farthest distance from the Sun at aphelion (from the Greek. aro - away from and helios- Sun) - the greatest distance from the Sun - July 5. It is equal to 152 million km. At this time in the Northern Hemisphere summer.
Fig. 4. The movement of the Earth around the Sun
The annual movement of the Earth around the Sun is observed by the continuous change in the position of the Sun in the sky - the midday height of the Sun and the position of its rising and setting change, the duration of the light and dark parts of the day changes.
When moving in orbit, the direction of the earth's axis does not change, it is always directed towards the North Star.
As a result of a change in the distance from the Earth to the Sun, as well as due to the tilt of the Earth's axis to the plane of its motion around the Sun on Earth, an uneven distribution of solar radiation is observed throughout the year. This is how the seasons change, which is characteristic of all planets whose rotation axis tilt to the plane of its orbit (ecliptic) differs from 90 °. The planet's orbital speed in the Northern Hemisphere is higher in winter and less in summer. Therefore, the winter half-year lasts 179, and the summer one - 186 days.
As a result of the movement of the Earth around the Sun and the inclination of the Earth's axis to the plane of its orbit by 66.5 ° on our planet, there is not only a change in the seasons, but also a change in the length of the day and night.
The rotation of the Earth around the Sun and the change of seasons on Earth are shown in Fig. 81 (days of equinox and solstice according to the seasons in the Northern Hemisphere).
Only twice a year - on the days of the equinox, the length of the day and night on the whole Earth is practically the same.
Equinox - the moment in time at which the center of the Sun, with its apparent annual movement along the ecliptic, crosses the celestial equator. There are spring and autumn equinoxes.
The inclination of the Earth's axis of rotation around the Sun on the equinox days of March 20-21 and September 22-23 turns out to be neutral in relation to the Sun, and the parts of the planet facing it are uniformly illuminated from pole to pole (Fig. 5). The sun's rays fall steeply at the equator.
The longest day and the shortest night are observed on the summer solstice.
Fig. 5. Illumination of the Earth by the Sun on the days of the equinox
Solstice - the moment the center of the Sun passes the ecliptic points farthest from the equator (solstice points). Distinguish between summer and winter solstices.
On the day of the summer solstice, June 21-22, the Earth is in such a position in which the northern end of its axis is tilted towards the Sun. And the rays fall vertically not on the equator, but on the northern tropic, the latitude of which is 23 ° 27 "All day long, not only the polar regions are illuminated, but also the space beyond them to the latitude 66 ° 33" (Arctic Circle). In the Southern Hemisphere at this time, only that part of it that lies between the equator and the southern Arctic Circle (66 ° 33 ") is illuminated. Behind it, the earth's surface is not illuminated on this day.
On the winter solstice, December 21-22, everything happens the other way around (Fig. 6). The sun's rays are already falling steeply on the southern tropic. Illuminated in the Southern Hemisphere are areas that lie not only between the equator and the tropic, but also around the South Pole. This situation continues until the vernal equinox.
Fig. 6. Illumination of the Earth on the day of the winter solstice
On two parallels of the Earth on the solstice days, the Sun at noon is directly above the observer's head, that is, at the zenith. Such parallels are called the tropics. In the Northern Tropic (23 ° N) the Sun is at its zenith on June 22, in the Southern Tropic (23 ° S) on December 22.
At the equator, day is always equal to night. The angle of incidence of sunlight on the earth's surface and the length of the day there change little, so the change of seasons is not pronounced.
Polar circles are remarkable in that they are the boundaries of areas where there are polar days and nights.
Polar day - the period when the Sun does not sink below the horizon. The further from the Arctic Circle near the pole, the longer the polar day. At the latitude of the Arctic Circle (66.5 °), it lasts only one day, and at the Pole - 189 days. In the Northern Hemisphere, at the latitude of the Arctic Circle, the polar day is observed on June 22 - the day of the summer solstice, and in the Southern Hemisphere at the latitude of the Southern Arctic Circle - on December 22.
polar night lasts from one day at the latitude of the Arctic Circle to 176 days at the poles. During the polar night, the Sun does not appear above the horizon. In the Northern Hemisphere at the latitude of the Arctic Circle, this phenomenon is observed on December 22.
It is impossible not to note such a wonderful natural phenomenon as white nights. White Nights - these are bright nights in early summer, when the evening dawn converges with the morning and twilight lasts all night. They are observed in both hemispheres at latitudes exceeding 60 °, when the center of the Sun at midnight drops below the horizon by no more than 7 °. In St. Petersburg (about 60 ° N) white nights last from June 11 to July 2, in Arkhangelsk (64 ° N) - from May 13 to July 30.
The seasonal rhythm in connection with the annual movement primarily affects the illumination of the earth's surface. Depending on the change in the height of the Sun above the horizon, five light belts. The hot belt lies between the North and South tropics (the Tropic of Cancer and the Tropic of Capricorn), occupies 40% of the earth's surface and is distinguished by the largest amount of heat coming from the Sun. Between the tropics and the Arctic Circle in the Southern and Northern Hemispheres, there are moderate light belts. The seasons of the year are already expressed here: the farther from the tropics, the shorter and cooler the summer, the longer and colder the winter. The polar belts in the Northern and Southern Hemispheres are bounded by the Arctic Circle. Here, the height of the Sun above the horizon is low throughout the year, so the amount of solar heat is minimal. The polar belts are characterized by polar days and nights.
Depending on the annual movement of the Earth around the Sun, there are not only the change of seasons and the associated irregularity of the illumination of the Earth's surface in latitudes, but also a significant part of the processes in the geographic envelope: seasonal changes in the weather, the regime of rivers and lakes, rhythm in the life of plants and animals, types and terms of agricultural work.
The calendar. The calendar - system of calculating long periods of time. This system is based on periodic natural phenomena associated with the movement of heavenly bodies. The calendar uses astronomical phenomena - the change of the seasons, day and night, the change in lunar phases. The first calendar was the Egyptian, created in the 4th century. BC e. On January 1, 45, Julius Caesar introduced the Julian calendar, which is still used by the Russian Orthodox Church. Due to the fact that the duration of the Julian year is more than the astronomical one by 11 minutes 14 seconds, by the 16th century. the "error" accumulated in 10 days - the day of the vernal equinox did not come on March 21, but on March 11. This mistake was corrected in 1582 by the decree of Pope Gregory XIII. The count of days was moved 10 days ahead, and the day after October 4 was prescribed to be considered Friday, but not October 5, but October 15. The vernal equinox was again returned to March 21, and the calendar became known as the Gregorian. It was introduced in Russia in 1918. However, it also has a number of disadvantages: unequal length of months (28, 29, 30, 31 days), inequality of quarters (90, 91, 92 days), inconsistency of the numbers of months by days of the week.
Teamis any organizational group of people.
In pedagogical literature, a collective is an association of pupils that differ in a number of characteristics:
· Common socially significant goal.
· General compatible activities to achieve the goal.
· The general organization of this activity, the attitude of responsible dependence.
· Commonly-elected governing body.
· Favorable psychological climate.
Children's collective how is the system:
1. A limited part of a more complex association, an educational collective, which includes, in addition to children, a collective of teachers.
2. A relatively autonomous system which is characterized by the processes of self-organization, self-government.
3. Coordinated unity of the two structures:
Formal (influenced by adults)
Informal (in the process of communication)
4. The subject of activities for the implementation of common socially significant goals.
5. The subject of education in relation to the personality of each of its members.
Functions of the children's collective:
1. Educational.
2. Organizational.
3. Regulatory.
4. Stimulating.
The principles of forming a team of children:
1. Organization of the detachment.
2. Organization of a multi-age team.
The children's team can be of the same age or different age. Boys and girls differ in development.
Z mәdәniyateңneң үzenchәleklәren saklarga, head halyklarnyң mңdniyaten һәm traditionlaryn hөrmәt itәrgә.
Geographical consequences of the inclination of the earth's axis to the orbital plane
Geographic implications of the Earth's annual motion:
1. The earth's axis is inclined with respect to the orbital plane and forms an angle with it equal to 66 0 33 /. In the process of movement, the axis moves translationally, so 4 characteristic points appear in the orbit:
March 21 and September 23 - days of equinoxes - the inclination of the earth's axis turns out to be neutral in relation to the Sun, and the parts of the planet facing it are uniformly illuminated from pole to pole. At all latitudes during these periods, the duration of the day and night is 12 hours.
June 21 and December 22 - days of summer and winter solstices - the plane of the equator is tilted relative to the sun's ray at an angle of 23 0 27 /, the Sun at this moment is at its zenith over one of the tropics.
2. The tilt of the earth's axis to the orbital plane is associated with the presence of such characteristic parallels as the tropics and polar circles. The polar circle is a parallel, the latitude of which is equal to the angle of inclination of the earth's axis to the plane of the orbit (66 0 33 /). Tropic is a parallel, the latitude of which complements the angle of inclination of the earth's axis to a straight line (23 0 27 /). The polar circles are the boundaries of the distribution of the polar day and polar night. The tropics are the boundaries of the zenith position of the sun at noon. In the tropics, the sun is at its zenith once, in the space between them - twice a year.
3. Change of seasons (winter, spring, summer, autumn - the northern hemisphere (SP); summer, autumn, winter and spring - the southern hemisphere (SP). An uneven distribution of the year between seasons is characteristic (spring contains 92.8 days, summer - 93.6, autumn - 89.8, winter - 89.0), which is explained by the division of the elliptical orbit of the Earth by the lines of solstices and equinoxes into unequal parts, which take different times to pass.
4. Formation of belts of illumination, which are distinguished by the height of the Sun above the horizon and the duration of illumination. IN hot belt, located between the tropics, the Sun is at its zenith at noon twice a year. On the lines of the tropics, the Sun is at its zenith only once a year: in the Northern Tropic (Tropic of Cancer), the Sun is at its zenith at noon - June 22, in the Southern Tropic (Tropic of Capricorn) - on December 22.
Between the tropics and the polar circles stand out two moderate belts. In them, the Sun never stands at its zenith, the length of the day and the height of the Sun above the horizon vary greatly throughout the year.
Between the polar circles and the poles are located two cold zones, there are polar days and nights here. Consequently, there are days in a year when the Sun does not appear over the horizon at all or does not sink below the horizon.
5. The change of seasons determines the annual rhythm in GO. In a hot zone, the annual rhythm depends mainly on changes in moisture, in a moderate zone - on temperature, in a cold zone - on lighting conditions.
24. The daily movement of the Earth and its geographical consequences. The concept of "sidereal day" and "solar day"
The daily rotation of the Earth around the axis and its consequences.The earth rotates from west to east counterclockwise, completing a full revolution per day. The axis of rotation is deflected by 23 0 27 / from the perpendicular to the plane of the ecliptic. Average angular velocity of rotation, i.e. the angle by which the point on the earth's surface is displaced is the same for all latitudes and is 15 0 in 1 hour. Linear velocity, i.e. the path traversed by a point per unit of time depends on the latitude of the place. The geographic poles do not rotate, where the speed is zero. At the equator, each point passes the longest path and has the highest speed - 455 m / s. The speed is different on one meridian, the same on one parallel.
The geographic consequences of the Earth's diurnal rotation are:
1. Change of day and night, i.e. change during the day in the position of the Sun relative to the horizon plane of a given point (axial rotation gives the basic unit of time - a day). This change is associated with the daily rhythm of solar radiation, the intensity of which depends on the angle of inclination of the earth's axis, the rhythms of heating and cooling of local air circulation, and the vital activity of living organisms.
2. Different local time at the same moment on different meridians (difference 4 minutes for each degree of longitude).
3. Existence coriolis forces(the deflecting action of the Earth's rotation). The Coriolis force is always perpendicular to movement, directed to the right in the northern hemisphere and to the left in the southern. Its value depends on the speed and mass of the moving body, as well as on the latitude of the place: F \u003d 2mυwsinφ,
where m is body weight; υ is the linear velocity of the body; w is the angular velocity of the Earth's rotation (it is important only in the secular aspect, for short periods of time the angular velocity is assumed to be constant); φ is the latitude of the location.
At the equator, the Coriolis force is zero, and its magnitude increases towards the poles. The Coriolis force contributes to the formation of atmospheric vortices, affects the deflection of sea currents. Thanks to it, the right banks of the rivers in the joint venture and the left banks in the SP are washed away.
4. The rotation of the Earth (together with the spherical shape) in the field of solar radiation (light and heat) determines the west-east extent of the natural zones.
5. Compression of the terrestrial spheroid, which is explained by the simultaneous action on any point of the planet of two forces: gravity (directed towards the center) and centrifugal (perpendicular to the axis of rotation), giving the force of gravity. Gravity is the vector difference between gravity and centrifugal force. The centrifugal force rises from zero at the poles to its maximum value at the equator. In accordance with the decrease in centrifugal force from the equator to the pole, the force of gravity increases in the same direction and reaches a maximum at the pole (equal to the force of gravity).
The deformation of the Earth's figure due to the differences in the force of gravity further emphasizes the increase in centrifugal force (decrease in the force of gravity) towards the equator and, thus, further contributes to the flattening of the Earth from the poles.
6. The axis of rotation, the poles and the equator are the basis of the geographic coordinate system. The equator serves as a plane of symmetry, relative to which the lighting belts are located, the amount of solar radiation and other important parameters change. The direction of the Coriolis force depends on the hemisphere (Northern and Southern), and its magnitude depends on latitude, the poles do not participate in the daily rotation.
7. Deformation of the Earth's figure - flattening at the poles (polar compression) associated with an increase in centrifugal force from the poles to the equator.
The rotation of the Earth around its axis serves as the basis for determining time using astronomical observations. Solar days used in everyday life are measured by the duration of one revolution of the Earth in relation to the Sun. Sidereal days are determined by the duration of one revolution of the Earth in relation to the stars.
Sidereal days are 23 hours. 56min. 4c. This is the time it takes for a star to cross the celestial meridian twice in succession. A solar day is equal to 24 hours - this is the time interval between two successive passages of the Sun through the celestial meridian (at noon).
Solar days are about 4 minutes longer than stellar due to the fact that the Earth simultaneously rotates on its axis and revolves around the Sun. Therefore, for the new appearance of the Sun on the celestial meridian of the Earth, it is necessary to rotate around its axis a little more than once.