The idea of extreme day and night range?

Extreme day is the phenomenon that the sun never sets all day in the polar circle, so it is also called "eternal day". Extreme sunlight only occurs in the southern part of the earth and in the Arctic Circle. When the sun shines directly in the northern hemisphere, the extreme day appears in the North Pole; The polar night appears in the Antarctic region. When the sun shines directly into the southern hemisphere, the situation is just the opposite. If the sun shines directly at the north latitude 10, there will be an extreme day at 80-90 north latitude and an extreme night at 80-90 south latitude (excluding atmospheric refraction and the radius of the sun's looking around). In the Antarctic and Arctic circles, there are extreme days and nights every year. Its duration varies with latitude. In the Antarctic and Arctic, there are polar days and polar nights for half a year every year. Except for the South Pole and the North Pole, the height and direction of the sun are still changing during extreme daytime.

Extreme day: In the Antarctic region, the phenomenon that the sun never sinks to the horizon within 24 hours local time is called extreme day. In the Antarctic, it is extremely bright for half a year; If refraction is considered, it should be a little more than half a year. The extreme sunrise in Antarctica occurs in the summer of the southern hemisphere.

Extreme night: Contrary to extreme day, in the Antarctic region, the phenomenon that the sun is always below the horizon within 24 hours of local time is called extreme night. In the Antarctic, half a year should be the polar night; If refraction is considered, it should be slightly less than half a year. The Antarctic polar night is just the opposite of the winter polar day in the southern hemisphere.