What is night?

What is night? Night is an exact polarity for day. It is a time when there is no light (except the mob light) and there is no sun that provides us with bright and warm light, and there is a total sleepiness of the whole world. And there are stars at night, beautiful tiny gleams we can't see at day. So, night is a beautiful polarity for beautiful day.

From the scientific point of view, night is a period o time during which the celestial body Sun situated lower than horizon line for certain area of another celestial body. So, it is a period of time when people on the opposite side of Earth see no sun and sun light, while people of another side of Earth see both and have their day.

As for the length of night it is peculiar for different countries, different seasons and different days. It is common for people to recognize days of solstice. Those are days when length of night is changed in one or another way. So, people say that the days of summer solstice is a day since which night increases every day. At the time the day of winter solstice is a polarity for day of summer solstice.

The length of night for each peculiar part of Earth depends on the longitude of that areas and axes degree and many other characteristics. The most interesting phenomenon of length of night is those nights people have at polar latitudes. The might lasts even longer than sun day. Those nights may last for about two or three sun days.