How to judge the solar terms according to the polar view of the terminator line?

The way to solve the problem can be divided into two steps: the first step is to find out the nature of the pole according to the rotation direction, and the second step is to use the extreme day and night phenomenon of the polar circle.

Interpretation method 1 determine the north and south poles and the termination line: a. If it is side view, usually the north pole is above and the south pole is below. B if it is a polar top view, the north and south poles can be determined according to the feature that the earth's rotation direction is "north to south". C. Judging the morning line and the dark line according to the rotation direction of the earth: along the rotation direction of the earth, the dividing line between the daytime hemisphere and the night hemisphere is the dark line, and vice versa. (2) Determine the date and solar terms: There is an extreme solar phenomenon in the Arctic Circle, that is, the summer solstice in the northern hemisphere (June 22nd); The arctic circle has the phenomenon of extreme night, which is the winter solstice in the northern hemisphere (65438+February 22); When the termination line coincides with the meridian, it is the vernal equinox (March 2 1 day) or the autumnal equinox (September 23).