For a very long time, people thought that our planet has a flattened shape and lies on 3 whales. A person is unable to notice its rotation, being on it itself. The reason for this is the size. They matter a lot! The size of a man is too small in relation to the size of the globe. Time went forward, science progressed, and with it people's ideas about their own planet.
What have we come to today? Is it true that and not vice versa? What other astronomical knowledge in this area is valid? About everything in order.
Along its axis
Today we know that it takes part in two types of its movement simultaneously: the Earth revolves around the Sun and along its own imaginary axis. Yes, axles! Our planet has an imaginary line that "pierces" the surface of the earth at its two poles. Draw the axis mentally into the sky, and it will pass next to the North Star. That is why this point always seems to us motionless, and the sky seems to be rotating. We think that we are moving from east to west, but we note that it only seems to us! Such a movement is visible, since it is a reflection of the present rotation of the planet - along the axis.
The daily rotation lasts exactly 24 hours. In other words, in one day the globe performs one full circle along its own axis. Each of the earthly points first passes through the illuminated side, then the dark side. And a day later, everything repeats again.
For us, it looks like a constant change of days and nights: morning - afternoon - evening - morning ... If the planet did not rotate in this way, then on the side facing the light there would be eternal day, and on the opposite - eternal night. Horrible! It's good that it's not! In general, we figured out the daily rotation. Now let's find out how many times the Earth revolves around the Sun.
Solar "round dance"
This is also not visible to the naked eye. However, this phenomenon can be felt. We all know very well the warm and cold seasons. But what do they have in common with the movements of the planet? Yes, they have everything in common! The earth revolves around the sun in three hundred and sixty-five days, or one year. In addition, our globe is a participant in other movements. For example, together with the Sun and its "colleagues" - the planets, the Earth moves relative to its own galaxy - the Milky Way, which, in turn, moves relative to its "colleagues" - other galaxies.
It is important to know that in the whole Universe nothing is immovable, everything flows and changes! Note that the movement of the celestial body that we see is just a reflection of a rotating planet.
Is the theory correct?
Today, many people are trying to prove the opposite: they believe that it is not the Earth that revolves around the Sun, but, on the contrary, the celestial body around the globe. Some scientists talk about the joint movement of the Earth and the Sun, which occurs relative to each other. Perhaps someday the world's scientific minds will turn "upside down" all the scientific ideas about space known today! So, all the dots over the “and” are dotted, and you and I learned that around the Sun (at a speed, by the way, about 30 kilometers per second), and it makes a full revolution in 365 days (or 1 year), at the same time Our planet rotates its axis in a day (24 hours).
Scientists have come to the following conclusions - the speed of rotation of the earth is falling. This leads to the following consequences - the day lengthens. If you do not go into details, then in the northern hemisphere the bright part of the day becomes somewhat longer than in winter. But this interpretation is only suitable for the uninitiated. Geophysicists come to deeper conclusions - the days increase their time frames not only in the spring. The reason for the lengthening of the day lies primarily in the influence of the moon.
The force of attraction of the natural satellite of the earth is so great that it causes excitement in the oceans, causing them to sway. At the same time, the earth acts by analogy with the figure skaters, who, in order to slow down the rotation during the execution of their programs, put out their hands. It is because of this that after some time in an ordinary earthly day there will be one hour more than we are used to. One astronomer from the UK came to the conclusion that since 700 BC there has been a continuous slowdown in the rotation of the Earth around its axis. He calculated the speed of rotation of the Earth, based on data that have survived since those times - clay tablets and historical evidence that describes lunar and solar eclipses. Based on them, the scientist calculated the position of the Sun and was able to determine what braking distance our planet was doing relative to its star. For 530 million years, the Earth's rotation rate was much slower, and there were only 21 hours in a day.
And the dinosaurs that inhabited the expanses of our planet a hundred million years ago already lived at 23 hours a day. This can be determined by examining the calcareous deposits that the corals left behind. Their thickness depends on what season is present on the planet. On this basis, it is possible to determine quite accurately - in what interval were the springs from each other. And this duration is reduced throughout the entire existence of our planet. Half a million years ago, our planet was moving around the axis faster, while the movement around the star remains constant. This means that the year for all these millions of years has remained the same, it has the same number of hours. But this year there were not 365 days, as today, but 420. After the emergence of mankind, this trend did not cease to exist. The speed of the Earth's rotation around its axis is constantly slowing down. The Journal for the History of Astronomy published an article on this phenomenon in 2008.
Stephenson, who works at the University of Durham (Great Britain), in order to fully verify and confirm the hypothesis, analyzed hundreds of eclipses that have occurred over the past 2.7 thousand years. In the clay tablets of ancient Babylon, all celestial phenomena recorded in cuneiform are described in great detail. Scientists noted both the time of the event and its exact date. Another feature - a total solar eclipse on Earth is observed not so often, only once every 300 years. At this moment, the Sun is completely hidden behind the Earth and complete darkness descends on it for several minutes. Very often, ancient scientists described both the beginning of an eclipse and its end with great accuracy. And these data were used by a modern astronomer in order to determine the position of our star relative to the Earth.
The recalculation of the dates of the Babylonian calendar took place according to specially compiled tables, which facilitated the work. It is these data that allow astronomers to determine with great accuracy. How did the deceleration of the Earth occur? Correct data on its position relative to the Sun, allow you to determine its position at the moment when it passes by the Sun. The trajectory of the planet around the Sun depends on the movement around its own axis. Terrestrial time, which is derived from this dependence, is an independent quantity. This universal time is a generally accepted indicator, which is calculated based on how the earth rotates on its axis and in what position it is relative to the sun. This universal time is constantly shifting back, since every year one more second is added to the year, which is caused, precisely, by the process of Earth's deceleration. And as it turned out, the difference between terrestrial and universal time is getting bigger, depending on how long ago the solar eclipse happened. This can only mean one thing - every millennium adds as much as 0.002 seconds to the day. These data are also confirmed by changes carried out from satellite laboratories launched into earth's orbit.
The deceleration rate is fully consistent with the calculations made by a scientist from the UK. And at the time when the flourishing of the Babylonian civilization was observed, the day on earth lasted somewhat less, the difference with modern time was 0.04 seconds. And this meager deviation was calculated by Stephenson due to the fact that he was able to compare universal time and evaluate the errors accumulated in it. Since about a million days have passed from the year 700 to the present day, we could translate our electronic clocks by 7 hours, so much time was added to the time of the Earth's rotation around its axis.
Recent years have become an exception for the Earth, during this time there is practically no lengthening of the day and the Earth continues to move at a constant speed. The masses inside the earth may have begun to compensate for the fluctuations caused by the influence of the magnetic field of the moon. And the acceleration of the planet's movement could be caused, for example, by the earthquake in Argentina in 2004, after which the day was shortened by 8 millionths of a second. The shortest day in history was recorded in 2003, when they did not even have 24 hours (1,005 seconds were not enough). The international service that studies the rotation of the Earth and geophysicists are closely watching the problem of slowing down the speed of the earth's rotation and the processes that affect its movement. After all, this will allow us to give answers to many global questions related to the structure of the planet and the processes that occur in deep structures - the mantle and the core. What covers the research and scientific activities of seismologists and geophysicists.
The average distance from the Earth to the Sun is approximately 150 million kilometers. But since rotation of the earth around the sun occurs not in a circle, but in an ellipse, then at different times of the year the Earth is either a little further from the Sun, or a little closer to it.
In this real time-lapse photo, we see the path the Earth makes in 20-30 minutes relative to other planets and galaxies, rotating around its axis.
Change of seasons
It is known that in summer, in the hottest time of the year - in June, the Earth is about 5 million kilometers farther from the Sun than in winter, in the coldest season - in December. Hence, change of seasons happens not because the Earth is further or closer to the Sun, but for another reason.
The Earth, in its translational motion around the Sun, constantly maintains the same direction of its axis. And with the translational rotation of the Earth around the Sun in orbit, this imaginary earth's axis is always inclined to the plane of the earth's orbit. The reason for the change of seasons is precisely the fact that the Earth's axis is always inclined to the plane of the Earth's orbit in the same way.
Therefore, on June 22, when our hemisphere has the longest day of the year, the Sun also illuminates the North Pole, and the South Pole remains in darkness, since the sun's rays do not illuminate it. While summer in the Northern Hemisphere has long days and short nights, in the Southern Hemisphere, on the contrary, there are long nights and short days. There, therefore, it is winter, where the rays fall "obliquely" and have a low calorific value.
Time difference between day and night
It is known that the change of day and night occurs as a result of the rotation of the Earth around its axis, (more details:). BUT time difference between day and night depends on the rotation of the earth around the sun. In winter, December 22, when the longest night and the shortest day begin in the Northern Hemisphere, the North Pole is not illuminated by the Sun at all, it is “in darkness”, and the South Pole is illuminated. In winter, as you know, the inhabitants of the Northern Hemisphere have long nights and short days.
On March 21–22, the day is equal to the night, the vernal equinox; the same equinox autumn- happens on September 23rd. These days, the Earth occupies such a position in its orbit relative to the Sun that the sun's rays simultaneously illuminate both the North and South Poles, and they fall vertically on the equator (the Sun is at its zenith). Therefore, on March 21 and September 23, any point on the surface of the globe is illuminated by the Sun for 12 hours and is in darkness for 12 hours: day and night all over the world.
Climatic zones of the Earth
The rotation of the Earth around the Sun explains the existence of various climatic zones of the Earth. Due to the fact that the Earth has a spherical shape and its imaginary axis is always inclined to the plane of the earth's orbit at the same angle, different parts of the earth's surface are heated and illuminated by the sun's rays in different ways. They fall on separate areas of the earth's surface at different angles of inclination, and as a result, their calorific value in different zones of the earth's surface is not the same. When the Sun is low above the horizon (for example, in the evening) and its rays fall on the earth's surface at a small angle, they heat very little. On the contrary, when the Sun is high above the horizon (for example, at noon), its rays fall on the Earth at a large angle, and their calorific value increases.
Where the Sun is at its zenith on some days and its rays fall almost vertically, there is the so-called hot belt. In these places, animals have adapted to the hot climate (for example, monkeys, elephants and giraffes); tall palm trees, bananas grow there, pineapples ripen; there, under the shadow of the tropical Sun, spreading their crown widely, there are gigantic baobab trees, the thickness of which in girth reaches 20 meters.
Where the sun never rises high above the horizon, there are two cold zones with poor flora and fauna. Here the animal and plant world is monotonous; large areas are almost devoid of vegetation. Snow covers boundless expanses. Between the hot and cold zones are two temperate belts, which occupy the largest areas of the surface of the globe.
The rotation of the Earth around the Sun explains the existence five climatic zones: one hot, two moderate and two cold.
The hot belt is located near the equator, and its conditional boundaries are the northern tropic (the tropic of Cancer) and the southern tropic (the tropic of Capricorn). The conditional boundaries of the cold belts are the northern and southern polar circles. Polar nights last there for almost 6 months. Days are the same length. There is no sharp boundary between the thermal zones, but there is a gradual decrease in heat from the equator to the South and North Poles.
Around the North and South Poles, huge spaces are occupied by continuous ice fields. In the oceans washing these inhospitable shores, colossal icebergs float (more:).
North and South Pole explorers
Reach North or South Pole has long been a daring dream of man. Brave and tireless Arctic explorers have made these attempts more than once.
So was the Russian explorer Georgy Yakovlevich Sedov, who in 1912 organized an expedition to the North Pole on the ship St. Foca. The tsarist government was indifferent to this great undertaking and did not provide adequate support to the brave sailor and experienced traveler. Due to lack of funds, G. Sedov was forced to spend the first winter on Novaya Zemlya, and the second on. In 1914, Sedov, together with two companions, finally made the last attempt to reach the North Pole, but the state of health and strength changed this daring man, and in March of that year he died on the way to his goal.
More than once, large expeditions on ships to the Pole were equipped, but even these expeditions failed to reach their goal. Heavy ice “fettered” the ships, sometimes breaking them and taking them away with their drift far in the direction opposite to the intended path.
Only in 1937, for the first time, was a Soviet expedition delivered by airships to the North Pole. The brave four - astronomer E. Fedorov, hydrobiologist P. Shirshov, radio operator E. Krenkel and the old sailor, expedition leader I. Papanin - lived on a drifting ice floe for 9 months. The huge ice floe sometimes gave cracks and collapsed. Brave researchers were more than once threatened with the danger of dying in the waves of the cold Arctic sea, but, despite this, they carried out their scientific research where no man had ever set foot before. Important research has been carried out in the fields of gravimetry, meteorology and hydrobiology. The fact of the existence of five climatic zones associated with the rotation of the Earth around the Sun has been confirmed.
It took man many millennia to understand that the Earth is not the center of the universe and is in constant motion.
The phrase of Galileo Galilei "And yet it spins!" forever went down in history and became a kind of symbol of that era when scientists from different countries tried to refute the theory of the geocentric system of the world.
Although the rotation of the Earth was proven about five centuries ago, the exact reasons that prompt it to move are still unknown.
Why does the earth spin on its axis?
In the Middle Ages, people believed that the Earth was stationary, and the Sun and other planets revolved around it. Only in the 16th century did astronomers manage to prove the opposite. Despite the fact that many associate this discovery with Galileo, in fact it belongs to another scientist - Nicolaus Copernicus.
It was he who in 1543 wrote the treatise "On the Revolution of the Celestial Spheres", where he put forward a theory about the motion of the Earth. For a long time this idea did not receive support either from his colleagues or from the church, but in the end it had a huge impact on the scientific revolution in Europe and became fundamental in the further development of astronomy. 
After the theory of the rotation of the Earth was proven, scientists began to look for the causes of this phenomenon. Over the past centuries, many hypotheses have been put forward, but even today no astronomer can accurately answer this question.
Currently, there are three main versions that have the right to life - theories about inertial rotation, magnetic fields and the impact of solar radiation on the planet.
Theory of inertial rotation
Some scientists are inclined to believe that once (during the time of its appearance and formation) the Earth spun, and now it rotates by inertia. Formed from cosmic dust, it began to attract other bodies to itself, which gave it an additional impulse. This assumption also applies to other planets in the solar system.
The theory has many opponents, since it cannot explain why at different times the speed of the Earth's movement either increases or decreases. It is also unclear why some planets in the solar system rotate in the opposite direction, such as Venus.
Theory about magnetic fields
If you try to connect two magnets with the same charged pole together, they will start to repel each other. The theory of magnetic fields suggests that the poles of the Earth are also charged in the same way and, as it were, repel each other, which causes the planet to rotate. 
Interestingly, scientists recently made a discovery that the Earth's magnetic field pushes its inner core from west to east and causes it to rotate faster than the rest of the planet.
Sun exposure hypothesis
The most probable is considered to be the theory of solar radiation. It is well known that it warms up the surface shells of the Earth (air, seas, oceans), but heating occurs unevenly, resulting in the formation of sea and air currents.
It is they who, when interacting with the solid shell of the planet, make it rotate. A kind of turbines that determine the speed and direction of movement are the continents. If they are not monolithic enough, they begin to drift, which affects the increase or decrease in speed.
Why does the earth move around the sun?
The reason for the revolution of the Earth around the Sun is called inertia. According to the theory about the formation of our star, about 4.57 billion years ago, a huge amount of dust arose in space, which gradually turned into a disk, and then into the Sun.
The outer particles of this dust began to combine with each other, forming planets. Even then, by inertia, they began to rotate around the star and continue to move along the same trajectory today. 
According to Newton's law, all cosmic bodies move in a straight line, that is, in fact, the planets of the solar system, including the Earth, should have long flown into outer space. But that doesn't happen.
The reason is that the Sun has a large mass and, accordingly, a huge force of attraction. The Earth, during its movement, is constantly trying to rush away from it in a straight line, but gravitational forces pull it back, so the planet is kept in orbit and revolves around the Sun.
Our planet is in constant motion. Together with the Sun, it moves in space around the center of the Galaxy. And that, in turn, moves in the universe. But the most important thing for all living things is the rotation of the Earth around the Sun and its own axis. Without this movement, the conditions on the planet would be unsuitable for sustaining life.
solar system
Earth as a planet of the solar system, according to scientists, was formed more than 4.5 billion years ago. During this time, the distance from the sun practically did not change. The speed of the planet and the gravitational pull of the sun balance its orbit. It is not perfectly round, but stable. If the force of attraction of the star were stronger or the speed of the Earth decreased noticeably, then it would fall on the Sun. Otherwise, sooner or later it would fly into space, ceasing to be part of the system.
The distance from the Sun to the Earth makes it possible to maintain the optimum temperature on its surface. The atmosphere also plays an important role in this. As the Earth rotates around the Sun, the seasons change. Nature has adapted to such cycles. But if our planet were further away, then the temperature on it would become negative. If it were closer, all the water would evaporate, since the thermometer would exceed the boiling point.
The path of a planet around a star is called an orbit. The trajectory of this flight is not perfectly round. It has an ellipse. The maximum difference is 5 million km. The closest point of the orbit to the Sun is at a distance of 147 km. It's called perihelion. Its land passes in January. In July, the planet is at its maximum distance from the star. The greatest distance is 152 million km. This point is called aphelion.
The rotation of the Earth around its axis and the Sun provides, respectively, a change in daily regimes and annual periods.
For a person, the movement of the planet around the center of the system is imperceptible. This is because the mass of the Earth is enormous. Nevertheless, every second we fly through space about 30 km. It seems unrealistic, but such are the calculations. On average, it is believed that the Earth is located at a distance of about 150 million km from the Sun. It makes one complete revolution around the star in 365 days. The distance traveled in a year is almost a billion kilometers.
The exact distance that our planet travels in a year, moving around the sun, is 942 million km. Together with her, we move in space in an elliptical orbit at a speed of 107,000 km / h. The direction of rotation is from west to east, that is, counterclockwise.
The planet does not complete a complete revolution in exactly 365 days, as is commonly believed. It still takes about six hours. But for the convenience of chronology, this time is taken into account in total for 4 years. As a result, one additional day “runs in”, it is added in February. Such a year is considered a leap year.
The speed of rotation of the Earth around the Sun is not constant. It has deviations from the mean. This is due to the elliptical orbit. The difference between the values is most pronounced at the points of perihelion and aphelion and is 1 km/sec. These changes are imperceptible, since we and all the objects around us move in the same coordinate system.
change of seasons
The rotation of the Earth around the Sun and the tilt of the planet's axis make it possible for the seasons to change. It is less noticeable at the equator. But closer to the poles, the annual cyclicity is more pronounced. The northern and southern hemispheres of the planet are heated by the energy of the Sun unevenly.
Moving around the star, they pass four conditional points of the orbit. At the same time, twice in turn during the semi-annual cycle, they turn out to be further or closer to it (in December and June - the days of the solstices). Accordingly, in a place where the surface of the planet warms up better, the ambient temperature is higher there. The period in such a territory is usually called summer. In the other hemisphere at this time it is noticeably colder - it is winter there.
After three months of such movement, with a frequency of six months, the planetary axis is located in such a way that both hemispheres are in the same conditions for heating. At this time (in March and September - the days of the equinox) the temperature regimes are approximately equal. Then, depending on the hemisphere, autumn and spring come.
earth axis
Our planet is a spinning ball. Its movement is carried out around a conditional axis and occurs according to the principle of a top. Leaning with the base in the plane in the untwisted state, it will maintain balance. When the speed of rotation weakens, the top falls.
The earth has no stop. The forces of attraction of the Sun, the Moon and other objects of the system and the Universe act on the planet. Nevertheless, it maintains a constant position in space. The speed of its rotation, obtained during the formation of the nucleus, is sufficient to maintain relative equilibrium.
The earth's axis passes through the planet's ball is not perpendicular. It is inclined at an angle of 66°33´. The rotation of the Earth on its axis and the Sun makes it possible to change the seasons of the year. The planet would "tumble" in space if it did not have a strict orientation. There would be no question of any constancy of environmental conditions and life processes on its surface.
Axial rotation of the Earth
The rotation of the Earth around the Sun (one revolution) occurs during the year. During the day it alternates between day and night. If you look at the Earth's North Pole from space, you can see how it rotates counterclockwise. It completes a full rotation in about 24 hours. This period is called a day.
The speed of rotation determines the speed of the change of day and night. In one hour, the planet rotates approximately 15 degrees. The speed of rotation at different points on its surface is different. This is due to the fact that it has a spherical shape. At the equator, the linear speed is 1669 km / h, or 464 m / s. Closer to the poles, this figure decreases. At the thirtieth latitude, the linear speed will already be 1445 km / h (400 m / s).
Due to axial rotation, the planet has a slightly compressed shape from the poles. Also, this movement "forces" moving objects (including air and water flows) to deviate from the original direction (Coriolis force). Another important consequence of this rotation is the ebbs and flows.
the change of night and day
A spherical object with the only light source at a certain moment is only half illuminated. In relation to our planet in one part of it at this moment there will be a day. The unlit part will be hidden from the Sun - there is night. Axial rotation makes it possible to change these periods.
In addition to the light regime, the conditions for heating the surface of the planet with the energy of the luminary change. This cycle is important. The speed of change of light and thermal regimes is carried out relatively quickly. In 24 hours, the surface does not have time to either overheat or cool below the optimum.
The rotation of the Earth around the Sun and its axis with a relatively constant speed is of decisive importance for the animal world. Without the constancy of the orbit, the planet would not have stayed in the zone of optimal heating. Without axial rotation, day and night would last for six months. Neither one nor the other would contribute to the origin and preservation of life.
Uneven rotation
Mankind has become accustomed to the fact that the change of day and night occurs constantly. This served as a kind of standard of time and a symbol of the uniformity of life processes. The period of rotation of the Earth around the Sun to a certain extent is influenced by the ellipse of the orbit and other planets of the system.
Another feature is the change in the length of the day. The axial rotation of the Earth is uneven. There are several main reasons. Seasonal fluctuations associated with the dynamics of the atmosphere and the distribution of precipitation are important. In addition, the tidal wave, directed against the motion of the planet, constantly slows it down. This figure is negligible (for 40 thousand years for 1 second). But over 1 billion years, under the influence of this, the length of the day increased by 7 hours (from 17 to 24).
The consequences of the Earth's rotation around the Sun and its axis are being studied. These studies are of great practical and scientific importance. They are used not only to accurately determine stellar coordinates, but also to identify patterns that can affect human life processes and natural phenomena in hydrometeorology and other fields.
