What is the global day and night length from the bisector to the hour during the revolution of the earth?

The vernal equinox refers to four solar terms: vernal equinox, autumnal equinox, summer solstice and winter solstice. During the revolution of the earth, the global day and night lengths of these four solar terms are as follows:

1. At the vernal equinox and the autumnal equinox, the length of day and night in the world is equal. This is because the sun is on the equator at the vernal equinox and the autumnal equinox, and day and night are the same in all parts of the earth.

2. During the summer solstice, the days in the northern hemisphere are long, the nights are short, and the days are the longest and shortest. This is because during the summer solstice, the sun shines directly on the tropic of cancer, and the northern hemisphere receives more sunlight than the southern hemisphere, so the days in the northern hemisphere are long and the nights are short. At this time, the northern hemisphere has the longest day and the shortest night.

3. During the winter solstice, the night in the northern hemisphere is longer than the day, and there is an extreme night phenomenon in the Arctic Circle and its north. This is because during the winter solstice, the sun shines directly on the tropic of Capricorn, and the northern hemisphere receives less sunshine than the southern hemisphere, so the night in the northern hemisphere is longer than the day. At this time, the Arctic Circle and its northern region will have the phenomenon of extreme night when the day is the shortest, that is, all day and all night.