How to determine the longest day length.

Instructions

The length of the day depends on the daily rotation of the Earth around its axis and orbital rotation around the Sun. Due to the rotation of the Earth in its orbit, the solar disk makes an annual visible bypass of the celestial sphere, moving along the ecliptic. In this regard, its declination changes and affects the length of the day differently at different geographical latitudes.

At the earth's equator, longitude daylight hours approximately constant and lasts about 12 hours. In the northern hemisphere of the Earth from March to September, daylight hours are more than 12 hours, and from the end of September to the end of March - less. In the Southern Hemisphere, everything is exactly the opposite. In the Arctic Circle in summer, daylight hours can be longer than 24 hours. This phenomenon is called polar day. At the poles, the day length is six months.

The shortest and longest daylight hours occur during winter and summer solstice. In the northern hemisphere, the winter solstice falls on December 21 or 22 (depending on the time zone), and the summer solstice falls on June 21 or 22 (depending on the time zone). leap year may occur on June 20). On the other side of the equator - in the Southern Hemisphere - the December solstice occurs in the summer, and the June solstice occurs in the winter.

During winter solstice The length of daylight hours is only 5 hours 53 minutes. - this is the shortest day of the year and, accordingly, the most long night. The summer solstice makes it possible to live the longest day - 17 hours 33 minutes. Having reached its maximum duration, from this moment the daylight hours begin to decrease until the winter solstice again comes, and it again begins to grow.

For a long time, in the traditions of many nations, the custom of celebrating the days of the winter and summer solstices has been preserved. So, in Russia, for example, short day The year is dedicated to a holiday called "Kolyada".

Historians claim that the ancient Egyptians knew about the solstice. There is a version that they built the majestic pyramids in such a way that on the day of the summer solstice the sun would set between them. You can verify this phenomenon by looking at the pyramids from the Sphinx.

The famous British Stonehenge, located 130 km from London, also conceals many mysteries and secrets. Some scientists call it an ancient observatory and also associate it with the summer solstice. Because it is on this day that the Sun rises above the Hillstone stone, located somewhat separately from the main structure.

There are places on Earth where the length of daylight is the same all year round- These are the areas lying on the equator. In all other areas of the planet, day length varies from a maximum of day summer solstice (June 22) to a minimum at day winter solstice (December 22). The closer to the equator the terrain is, the weaker these fluctuations are, and vice versa.

The Earth's axis is inclined to the ecliptic, that is, to the plane in which the Sun-Earth system is located, at an angle of approximately 66.6 degrees. If it were not for this tilt, the length of daylight at any point on Earth would be the same all year round, determined only by the geographic latitude of the area. But precisely because of this axis tilt, the Northern Hemisphere of the planet in the period between spring and autumn equinox(from March 21 to September 22) faces the Sun most of the day. The southern hemisphere, accordingly, faces the Sun for less of the day. Therefore, during the period when it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere. Well, when the Earth, having described a semicircle around the Sun, moves to the opposite point of its orbit, everything changes. Now, for most of the day, the Southern Hemisphere faces the Sun, so summer begins there, and winter begins in the Northern Hemisphere. Accordingly, the length of the day in the Northern Hemisphere is sharply reduced. On the territory of Russia, as well as in the entire Northern Hemisphere, the shortest winter season day– December 22. There are large areas where the polar nights occur in winter, meaning the sun does not rise above the horizon at all. This phenomenon is observed in places located north of the so-called Arctic Circle, that is geographical latitude, approximately equal to 66.5 degrees. The duration of the polar night ranges from several days to several months (in areas close to North Pole). After December 22, the day of the winter solstice, the length of daylight hours steadily increases. At first, this increase is almost imperceptible, since it is only a few minutes per day. But gradually the light day becomes significantly longer. And in day spring equinox(March 21), considered the beginning astronomical spring, its duration is compared with the duration of the night.

The signs are also justified from a religious point of view. Leap year is the only year when there is February 29, and this number is associated with Kasyan, which serves evil spirits and harms people.

What signs are there

It is not recommended to change anything in your life during a leap year, since all changes will be futile. You should not change your place of residence, place of work, type of activity, partner, etc. Some superstitious people do not even recommend changing your wardrobe and hairstyle.

According to signs, if you happen to experience a divorce during a leap year, you should buy a towel, take it to the church and give it to the women who clean there.

It is also not a good idea to get married during a leap year. There are a lot of superstitions associated with weddings that fall on a leap year. It is believed that a marriage entered into in a leap year will fall apart very quickly for one reason or another - conflicts, infidelity or the death of one of the spouses.

Planting at the beginning of the four-year cycle will not produce a large harvest. And according to another sign, if you plant something in the garden or garden during a leap year, you can “bury” yourself or one of your relatives, i.e. to the death of a family member. Therefore, when planting something in the ground, you need to say: “I plant it in a leap year, so it will die.”

Explanation will accept

Signs are a good thing. However, you shouldn't be so superstitious. If you have been offered a worthwhile job that you know you can handle, then why not accept this offer? And if you don’t calculate your strength, you can lose your job at any time.

Divorce is generally the last thing to happen in any year. If there is an opportunity to save a family, especially if there are children in it, then you need to use it. And it is not at all necessary that you will not be able to improve your personal life later. Of course, if in your new marriage you behave the same way as in your first, then there can be no talk of any happiness.

Well, the earth generally loves respect. If you plant something, then you need to talk to the earth, ask it for a good harvest. Saying a few words to the earth while planting something is not difficult, but the harvest can be bountiful.

Old people will not talk in vain. All signs are observations of more than one generation, so you should not brush them aside. But you shouldn’t believe blindly and thoughtlessly. Think logically about each sign and decide for yourself whether to believe in it or not.

Video on the topic

Sources:

• What number is missing 9,6,3, in order of decreasing to 10