The change of day and night is something that is established once and for all not only in ordinary life, but also in fairy-tale life. Although, this also happens in fairy tales - something breaks in the celestial mechanism and everything goes topsy-turvy. How long? Until a certain sorcerer appears, a master of magic who will fix everything.
Fairy tale “How night gave way to day”
In the heavenly Wonderland, everything went as usual. The sun sent golden rays to the earth. Before appearing in the sky, it looked at its sundial and knew exactly when to start shining and when to stop. As soon as the Sun went to bed, the Moon illuminated the earth. The stars helped the Moon. They tried their best to shine so that it would not be completely dark. The time when the Sun was shining was called “day”, and when the Moon and stars were shining - “night”.
But then one day the sundial broke. Day and night got mixed up, and such confusion began! No one knew exactly when dawn would be and when sunset would be. Many began to sleep restlessly at night, because no one really knew when to get up. The animals wandered as if lost. And the flowers forgot to open their buds.
Something urgently needed to be done. The old master Month volunteered to repair the sundial. He knew for sure that there should be a regular change of day and night. And the clock needs to be set so that at a certain moment the Sun gives way to the Moon.
Calling on magical powers for help, Master Month repaired the sundial. They began to walk like new. The sun was very happy when he saw his expensive watch.
Now the day will never be lost, and the night will immediately follow the day. Joy returned to the people. They liked both Sunny and Moon. The animals began to live their old lives. And the flowers opened their magnificent buds during the day, and closed them tightly at night. Let the buds rest so they can bloom again the next morning.
Questions and tasks for the fairy tale “How night followed day”
Imagine that you are on a miracle rocket and get to Wonderland. What would you be surprised by first?
Who would you make friends with in Wonderland?
Come up with a fairy tale about what will happen if the Sun and the Stars meet.
For the inhabitants of the Earth, the constant change of day and night is a common occurrence. All life on the planet is subject to the rhythmic alternation of dark and light times of day. However, this does not happen on all planets. For example, on Venus, which rotates very slowly around its axis, a year lasts less than two Venusian days. Jupiter rotates on its axis in about five Earth hours, and Saturn in ten.
The Earth makes a complete revolution around its axis in 23 hours 56 minutes 4.1 seconds, during which time day gives way to night - the sidereal day passes. The sidereal day is understood as the time of a complete revolution of our planet around its axis relative to the stars, considering them to be infinitely distant.
The alternation of day and night creates favorable conditions for all life on Earth. As you know, the Earth has the shape of a ball, and its axis of rotation is constantly inclined to the orbital plane at an angle of 66°33"22". Because of this, the sun's rays illuminate different parts of the earth's surface differently, therefore the length of day and night is different everywhere. It depends on the geographic latitude and time of year.
Only twice a year - on the days of the spring and autumn equinox (March 20-21 and September 23 - approx.) the length of day and night is the same at all latitudes of the Earth and is equal to 12 hours. The sun at this time is at its zenith above the equator, and the terminator - the line separating light and shadow on the surface of the planet, passes through the poles, coinciding with the direction of the meridians. The sun's rays fall on the equator these days at an angle of 90°, and the Northern and Southern Hemispheres heat up evenly.
On the days of the summer and winter solstice (June 22 and December 22 - note from the site), the planet experiences the longest night and the shortest day. For example, on June 22, the Sun is at its zenith over the Tropic of the North (23°07" N). In the Northern Hemisphere on this day at all latitudes, the day is longer than night. North of the Arctic Circle (66°33" N). ) polar day is established - the Sun does not set below the horizon for days. At the Arctic Circle, the polar day lasts a day, and at the poles it lasts up to six months. The Southern Hemisphere is less illuminated on June 22 than the Northern Hemisphere. Here, at all latitudes, the day is shorter than the night, and in the southern polar region the polar night sets in.
The Earth moves around the Sun, but the tilt of the planet's axis of rotation remains constant. Gradually, the height of the Sun above the horizon in the Northern Hemisphere decreases, the days become shorter and the nights longer. Finally, September 23 arrives - the day of the autumnal equinox, when the length of day and night is equal at all latitudes. From this moment on, the Sun begins to illuminate the Southern Hemisphere more. On December 22, the day of the winter solstice, the hemispheres seem to change places. On this day in the Southern Hemisphere at all latitudes, the day is longer than the night, and there is a polar day beyond the Antarctic Circle. At the same time, polar night reigns in the northern subpolar regions.
White nights occur south and north of the polar circles in both hemispheres. At this time, evening twilight turns into morning, and darkness does not come. Beyond the Arctic Circle, white nights precede the polar day - approx. At different latitudes, white nights differ in duration: for example, in St. Petersburg they last from June 11 to July 2, and in Arkhangelsk - from May 13 to July 30.
The satellite of our planet, the Moon, rotates around its axis at such a speed that when moving around the Earth, it is constantly turned to one side. If the Earth moved around the Sun like the Moon and was constantly turned to it with one side, the natural conditions on the planet would change enormously. One hemisphere of the Earth would be illuminated all year round, while the other would be constantly in shadow. The illuminated hemisphere would heat up to a temperature of more than 100 ° C, which means that all rivers, seas and oceans would evaporate. On the dark side of the planet, the temperature would be below -100 ° C, here all the water would turn into ice. At the border of light and shadow, due to large temperature differences, hurricanes would rage, earthquakes and volcanic eruptions would occur.
We often say: The sun has risen, the sun has risen high in the sky, the sun has set. Well, does the Sun really move across the sky, rising upward in the morning hours and descending to the horizon in the evening hours, or does it only seem to us that it is moving, but in reality our Earth is moving and we are moving with it?
Not so long ago (400 years ago) people believed that the Earth was motionless and the Sun was moving. But now we know that this is not so.
Indeed, it is difficult to allow the huge Sun, which is more than a million times larger in volume than the Earth, to move around it.
If we depict the Earth as the size of a grain of millet, then the Sun will appear to us as a ball the size of a human head. That's how big the Sun is. Moreover, it is so hot that even refractory substances (for example, iron) are in a gaseous state on it. Only due to the fact that the Earth is at a great distance from the Sun (almost 150 million kilometers), the Sun’s rays only warm the Earth’s surface and do not incinerate it.
And in order to have time to go around the Earth within a day, the huge Sun would have to move at colossal speed, flying more than 10,000 kilometers in one second. Isn’t it more reasonable to assume that not the Sun, but the Earth, rotating around its axis, turns to the Sun with its different sides? All those who have traveled on railways know well that when you look from the carriage of a moving train, it seems that trees, buildings and all other objects are quickly running back in the direction opposite to the movement of the train. None of us, of course, will make the mistake of thinking that the train is standing still, but that the trees and buildings are moving. But when we rotate with the Earth and look at the Sun, which, due to its distance, does not seem large to us at all, we can make a mistake and mistake the Earth’s movement for the movement of the Sun.
When 400 years ago the great scientist Nicolaus Copernicus wrote a book in which he proved that the visible movement of the Sun across the sky occurs from the rotation of the Earth, almost no one wanted to believe him, and the Pope even banned his book as being contrary to the Christian religion.
There is a story in the Bible about how the Jewish leader Joshua, seeing that he would not have time to defeat his enemies before dark, ordered the Sun to stop in the sky and thereby delayed the onset of night. The Catholic clergy referred to this biblical legend as a refutation of the teachings of Copernicus about the rotation of the Earth. After all, according to this legend, Joshua ordered the Sun to stop, not the Earth.
According to the teachings of Copernicus, the correctness of which science later confirmed with irrefutable evidence, the Earth rotates once a day around its axis passing through the north and south poles of the earth. This axis is, of course, imaginary.
If you take a ball, or better yet, a billiard ball, and spin it hard on a table, it will spin for a while. The axis of rotation of the ball, like the axis of rotation of the Earth, will be imaginary, but, looking at a rotating ball, it is not difficult to notice a point in the upper part of its surface through which this axis passes. The ball, of course, will soon stop due to friction on the table surface. The earth rotates in cosmic space without contacting any other bodies. Therefore, its rotation occurs without friction and there is no reason for it to stop.
If there were no celestial bodies - the Sun, stars and the Moon - in the cosmic space surrounding the Earth, we would not notice the rotation of the Earth. Now, although we do not feel that the Earth is spinning, we see that all the celestial bodies move across the sky in the same direction - from east to west. In reality, it is the Earth itself that rotates in the opposite direction - from west to east.
Thus, the change of day and night occurs because, due to the rotation of the Earth around its axis, the same place on the earth’s surface is either turned towards the Sun and illuminated by its rays, or turns away from the Sun. Look at fig. 1, showing the sun's rays hitting the globe on the left. Thanks to this, it is day on the left half of the globe, illuminated by the sun’s rays, and night on the right, unilluminated half.
Walk up to anyone you meet on the street and ask them to show in which direction the Earth rotates. The question is very simple, but many people will answer it incorrectly. And all because they never tried to understand what is really happening with the movement of the Earth.
There is hardly a person now who does not know about the rotation of the Earth. rises and sits on the rotation of the Earth and ensures the change of day and night. It’s very easy to understand this with the help of a globe and a table lamp, simulating that when the globe rotates, its sections will alternately go into the shadows and come out again into the light.
If you are in Russia, that is, in, and you follow the movement of the Sun, then you will see that for you it moves from left to right (if you are facing it). But this movement of the Sun is illusory; in fact, the Earth rotates - in the direction opposite to the apparent movement of the Sun. If you were in and also watched the Sun, facing it, then for you it would move from right to left.
What determines the change of seasons? A combination of two factors: the movement of the Earth around the Sun and the tilt of the Earth’s axis relative to it by 23.4º. If the earth's axis were not tilted, there would be no change of seasons. It is the tilt of the earth's axis that leads to the fact that the Sun alternately warms up the southern and northern hemispheres of the Earth. When summer begins in the northern hemisphere, winter begins. But it will pass, and everything will change - the Sun will begin to warm up the southern hemisphere more, and summer will come there. In the north, winter will reign.
The tilt of the earth's axis also leads to the fact that the length of day and night in different parts of the world is not the same and changes as the Earth moves around the Sun. It is unchanged only at the poles: at the equator, day and night at any time of the year are equal to twelve hours; at the poles, day and night always last six months. For other territories, the length of day and night smoothly changes from the summer solstice on June 21, when the day is maximum and the night is shortest, to the winter solstice on June 21, when the day is very short and the night is longest.
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- How does the day/night change occur?
Since ancient times, people have tried to understand and explain various natural phenomena - why it rains, why day turns into night, why the seasons change. But even now some people think that the change of seasons is due to the distance of the Earth from the Sun. Actually this is not true.
Instructions
Since the angle of inclination of the earth's axis does not change, then with the further movement of the planet in orbit (that is, the rest of the year), the South Pole turns out to be inclined towards the Sun. The southern hemisphere receives more warmth and light, and spring arrives south of the equator. The northern hemisphere, receiving less sunlight, is gradually cooling down. North of the equator it is winter.
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- how the seasons change
The alternation of day and night is so familiar to people that many do not even think about the reason for this phenomenon or its features. It is difficult to find a person who does not know about the rotation of the Earth or that it moves around the Sun. But how many people remember that day or night can last six months?
Every person who has studied at school knows that the basis of the change of day and night is the daily rotation of the Earth. In 24 hours it makes a full revolution around its axis, which ensures the alternation of day and night for most regions of the Earth. For most - but not for all. The Earth is tilted relative to the plane of its orbit by 23.4?. This leads to the fact that the Sun illuminates its surface unevenly. Territories near the North and South Poles find themselves in special lighting conditions: for six months, one of the poles night, while on the other – day. On one, the Sun simply does not set below the horizon, remaining in sight all the time; on the other, it does not appear above the horizon at all. White nights in St. Petersburg are associated precisely with the geographical location of the city - the Sun does not fall too low, so night doesn't come. But the nights not only in St. Petersburg, but also in all cities located higher (closer to the North Pole) 49? northern latitude. At this latitude day there is one white summer solstice night. The closer you are to the north from this latitude, the more . From latitude 65? and to the north one can observe continuous day, The sun does not set beyond the horizon at all. Similar phenomena are observed on the other side of the equator. Why polar day And night last exactly six months? Because the Earth revolves around the Sun, and exactly six months later, due to the tilt of its axis, it exposes the other pole to the Sun. The movement of the Earth around the Sun and the tilt of the Earth's axis also explain the alternation of seasons. Alternately, with a frequency of six months, the cold season is replaced by a warm one, and vice versa. When it is summer in the north, winter comes in the south. The easiest way to understand is to take a globe and illuminate it with a lamp simulating the Sun. By rotating the globe, you can easily see how the alternation of day and night occurs. And by moving the globe around the lamp, you will understand the reasons for the alternation of seasons. If you watch the Sun every day and mark exactly the floor day its height above the horizon, you can see that it changes. Once a year - June 21, at day summer solstice - it reaches its greatest height. The duration of daylight this day the largest, and night the shortest. Six months later, on December 21, at day winter solstice, the height of the Sun above the horizon will be the smallest, and day the shortest. For residents of the northern hemisphere, the summer solstice is day turning towards winter. Every day the Sun will rise above the horizon lower and lower, until day the winter solstice will not reach its lowest point. From this moment on, the turn towards summer will begin - the Sun will rise higher and higher, its rays will fall on the ground at an increasingly right angle, giving more heat.
It is traditionally believed that St. Petersburg is a city of bridges, palaces, canals, ancient mansions and white nights. The northern capital is also a city of tourists, who are fed not only with impressions, but with restaurants, bars, youth cafes, modern cinemas, and discos. There are entertainment facilities for them - billiards and tennis courts, bowling alleys. St. Petersburg has a huge number of establishments where you can celebrate a birthday for every taste.
It’s free, and in Japanese restaurants you can always order a platter for the whole group of friends.
Visit one of the many nightclubs if you prefer an active holiday. It’s not for nothing that St. Petersburg is called the club capital of Russia: there are establishments of various types here. You will remember for a long time day, held in the clubs “11”, “Behemoth”, “Air”, “Winter-Summer”, “Jelsomino”. The Begemot nightclub offers you to dance the night away to the electronic music of the best DJs. "Winter-Summer" is an elite place for fashionable parties. Here you will be surprised by an exquisite menu and a very advantageous location - overlooking the water. Music Bar “11” is a luxury karaoke with an amazing interior and excellent cuisine, and in the “Air” club you can not only dance on three different dance floors, but also swim in the pool and play volleyball.
Head to one of the sports and entertainment centers if you want to combine your holiday with sports competitions. Bowling fans will certainly enjoy clubs such as Bowling City, Golden Strike, and 7 Mile. Golden Strike has ten bowling lanes, four of which are suitable for children. In addition to seventeen bowling lanes, “7 Mile” has tables for American and Russian billiards, a bar, a cafe and a disco.
Rent one of the private boats if your day birth occurs during the warm season (from May to October). Take a walk along canals and rivers, under numerous bridges. You can also go out into the Gulf of Finland and continue the celebration there. However, it should be remembered that such a holiday requires increased caution and attention. Head to the Gulf of Finland coast if you don't want to celebrate day birth in a stuffy city. From Sestroretsk to Zelenogorsk there are a large number of cozy restaurants and entertainment venues. There you can grab a large table on the open veranda and then sunbathe on the sandy beach.
Sources:
- Internet guide to the concrete jungle
The reasons for the change of day and night are the constant and cyclical rotation of the Earth around its axis. This process is quite rapid, but we manage to notice it on dark evenings or watching the morning dawn. Thanks to the rays of the Sun, the surface of the planet warms up, and we can see the changing darkness and light.
Rays of the Sun and Light of the Moon
The reasons for the change of day and night is that the Earth rotates around an axis that we can mentally imagine. But it simultaneously rotates relative to the Sun. This happens as it moves in orbit around the star.
The reasons for the change of day and night lie in the movement of the Earth along an axis passing through the poles of the planet. She manages to turn around in 24 hours. But around the Sun there is a slower rotation - every 365 days.
The reason for the change of day and night is the rotation of the planet. It's different on different continents. For example, in St. Petersburg there is a season of white nights, and polar days can last more than a month.
What causes uneven daylight hours?
The length of day and night is not the same everywhere due to the fact that the imaginary axis of the Earth is slightly tilted relative to the Sun. Therefore, the rays fall differently on different hemispheres. Thanks to the redistribution of heat, life exists on the planet.
Having time to cool down overnight, the planet warms up during the day. Vital metabolic processes take place. We see the Earth in such a familiar way thanks to the unique movement of the planet. On different continents, flora and fauna differ due to the length of the day.
The pole can be in the shadow for six months - this time is called the polar night. Then comes the day at the pole for the next six months. While it is night at the North Pole, it is day at the South Pole, and vice versa.
If there were no usual days?
Due to the fact that the Earth is evenly illuminated by the Sun, life exists on the planet. Let's imagine that it would stop rotating, and on one side there would always be day, and the other would be forever deprived of light. The hemisphere under the Sun would heat up to a temperature at which all living things would dry out.
The second part of the planet would begin to freeze due to lack of sunlight. So in the present we have an ideal planet for life. The diversity of living things is amazing, and this is only possible due to the rotation of the Earth. The change of both day and night is important, as are the changes in weather due to the arrival of different seasons.