Causes and differences of the length of day and night between summer solstice and winter solstice.

Reason: The existence of the ecliptic angle makes the direct point of the sun move seasonally between the Tropic of Cancer. On the solstice of summer, the sun shines directly on the Tropic of Cancer, with long days and short nights in the northern hemisphere and short nights in the southern hemisphere. Winter is the opposite.

From summer to the sun, when the earth moves near perihelion, the revolution speed of the earth is slow, and the situation of long days and short nights in the northern hemisphere lasts for a long time. On the contrary, in winter, when the earth moves to the perihelion, the revolution speed of the earth is fast, and the long days and short nights in the southern hemisphere will last shorter than in the northern hemisphere.

The difference between summer solstice and winter solstice:

1, different times

The summer solstice is the tenth of the 24 solar terms, mainly from June 20 to 22 in the Gregorian calendar.

The winter solstice is the 22nd solar term among the 24 solar terms, and it is celebrated every year on 65438+February 2 1-23 in Gregorian calendar.

2. Different climatic characteristics

The climate from summer solstice is characterized by heavy rain, rainy days, high temperature and high humidity.

The climate from winter solstice is characterized by low temperature.

3. Different customs and activities

The custom activities from summer solstice mainly include offering sacrifices to gods and ancestors, avoiding summer and crouching.

Enjoy ancestor worship, banquets and other activities from winter solstice.

Extended data:

The law of the change of day and night length

1, the summer solstice points to the autumnal equinox: the days are long and the nights are short in the northern hemisphere.

Besides, the days are getting shorter and the nights are getting longer. The autumnal equinox has the same length of day and night, with the longest day and the shortest night in summer solstice. Extreme days appear in the Arctic, and the range of extreme days is shrinking. The days are short and the nights are long in the southern hemisphere. In addition, the nights are shorter and the days are longer. The day of the autumnal equinox is as long as the night, and the day of the summer solstice is the longest and shortest. There is an extreme night in Antarctica, and the range of extreme night is shrinking. ?

2. The winter solstice points to the vernal equinox: the days in the northern hemisphere are short and the nights are long.

The days are getting longer and the nights are getting shorter and shorter. At the vernal equinox, the length of day and night is equal, with the longest day and the shortest night in winter solstice. Extreme night appears in the North Pole, and the range of extreme night is shrinking. The days are long and the nights are short in the southern hemisphere. The nights are getting longer and the days are getting shorter and shorter. At the vernal equinox, the length of day and night is equal, and the daytime is the longest and shortest in winter solstice. Extreme day appears in Antarctica, and the range of extreme night is shrinking.