Variation law of day and night length in the southern hemisphere

The length of day and night can be divided into four solar terms according to the movement of the sun's direct point, namely, the vernal equinox (3.2 1), the summer solstice (6.22), the autumn equinox (9.23) and the winter solstice (12.22), in which the sun is directed at the equator, that is, the spring and autumn equinox, and the world is equally divided between day and night. Direct tropic of cancer, winter solstice in the southern hemisphere, short days and long nights; The tropic of Capricorn goes directly, and the southern hemisphere is solstice in summer, with long days and short nights.