Divide the spring equally.

the most special feature of "vernal equinox" is "equal share". As the folk proverb goes, "The vernal equinox and the autumnal equinox are equally divided day and night". In fact, according to China's own calendar, the meaning of "vernal equinox" is not just day and night. Because this day is also the most "right" day of spring.

since ancient times, China, which is located on the vernal equinox of the central axis of solar terms, has naturally attracted much attention. The spring equinox is a grand ceremony of the country. At this time, all the scenery outside the window has reached the right "middle" season: peaches and plums are half open, wild vegetables are new green, and green plums are like beans. In the poem, the sight of "spring people drinking spring wine and spring birds making spring sounds" always makes people yearn for this mid-spring time.

astronomical phenomena of the vernal equinox

The vernal equinox refers to the position of the sun between and 15 degrees of the yellow meridian in time period, from March 2th to April 5th. However, in practice, it usually refers to the day when the sun is really located at : March 2 or March 21. In ancient times, the vernal equinox was also called "Japan-China", "Day and night equinox" and "Mid-spring Moon". On this day, the sun shines directly on the equator of the earth, and the length of day and night is equal, and then the direct sunlight position gradually moves northward. ?

The traditional method of dividing the four seasons in China takes "Sili" in the 24 solar terms as the starting point of the four seasons, and "Bipolar" and "Ersolstice" as the midpoint. The division of four seasons in the west takes "dichotomy and dichotomy" as the starting point of four seasons, such as spring as the starting point and summer solstice as the ending point.

Western countries are located at a higher latitude, far from the intersection of Huang Chi, and taking "bisection to two" as the starting point of the four seasons can actually reflect the local climate better than "four stands". In the west, the four seasons divided by "dichotomy and dichotomy" are one and a half months later than those divided by China's traditional "Sili".

Baidu Encyclopedia-Vernal Equinox

Guangming. com-Vernal Equinox Swallows Return, the shore willows are green, and the day and night are equally divided.