In this article we will analyze an interesting topic: whether it happens that the day is equal to night and in what places you can find such miracles of nature.
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People are accustomed to the fact that on the globe, as a rule, only 2 times for a year and day and night are 12 hours. This happens in the fall and spring, in any corner of the world. But there are places where day and night the same throughout the year. Where are such places?
Where all year round the day equals the night: place on Earth
The duration of the day depends on what latitude one or another has, on the declination of our star. At the equator of our planet, it is approximately constant, that is, equal to 12 hours 7 minutes. A small deviation from half a day is present here. This is due to the fact that dawn and sunset are those moments when the center of the Sun crosses the true horizon.
In addition, refraction of the rays of the Sun can affect the duration. The slope of the planet’s axis to the ecliptic plane is determined due to the fluctuations in the duration of the day. In the northern part of the Earth, the duration of the day is more than 12 hours. It falls on March-Styabr. And during an increase in latitude, the duration of the day is growing, which becomes polar. From the first half of autumn and the first half of the spring, the duration of the day is less than 12 hours, and when the breadth begins to grow, the duration of the day decreases towards the polar night. In the southern part of our planet, everything happens the other way around.
But where is the day equal to the night? The answer is simple: the equator is constantly the same as the night. That is, its duration is 12 hours. The sun there is all the zenith daily there. At each scope of latitude, the day is also constantly equal to the night. Every day here the sun reaches one height. And only in the area of \u200b\u200bthe poles there is never true and present at night. The sun only slightly comes out from the horizon.
In the equator area, the sun constantly rises and sits relative to the horizon, that is, steeply. Therefore, there is a day throughout the year, as a night, and twilight, as a rule, is very short. The sun quickly goes beyond the horizon, and at 12 o’clock in the afternoon it will fall into zenith (2 times in 365 days: when the day of the equinox occurs). It is then that the declension of the sun is 0 °.
At the poles and at the equator: is the day equal to night or not?
The duration of one day directly depends on how angle the rays of the sun fall. It almost does not change above the equator line, therefore, the duration of one day and one night here is exactly the same.
At the North and South Pole, the day with the night is not the same. The sun there rises only once a year, sits also once when the solstice occurs. So, for example, at the North Pole the day goes to increase since March 21 - this is a polar day. And from September 25, he begins to decrease - this is a polar night, which ends on March 17.
If you take the South Pole, then on March 21 comes the moment when the day decreases, and on September 25 it increases. It turns out that both the longest day is 178 days at the northern and south poles, and the longest night is 187 days.
Video: days of equinox and seasons
