中华万年历

秋分是二十四节气中的第十六个节气，也是秋季的第四个节气。每年公历9月22日、23日或24日，当太阳到达黄经180°时为秋分。"分"即为"平分"、"半"的意思，"秋分"有两层含义：一是昼夜时间均等，秋分这一天，太阳直射赤道，南北半球昼夜平分，均为12小时；二是气候由热转凉，秋分日是秋季九十天的中分点，平分了秋季。秋分过后，太阳直射点继续由赤道向南半球推移，北半球各地开始昼短夜长，即一天之内白昼开始短于黑夜。秋分是一个特殊的日子，此时全球昼夜等长。秋分时节，我国大部分地区已经进入凉爽的秋季，南下的冷空气与逐渐衰减的暖湿空气相遇，产生一次次的降水，气温也一次次地下降。正如人们常说的那样，已经到了"一场秋雨一场寒"的时候。

Autumn Equinox (Qiufen) is the 16th solar term among the 24 solar terms and the fourth solar term of autumn, occurring around September 22-24 when the sun reaches 180 degrees celestial longitude. "Fen" means "to divide equally" or "half," and "Autumn Equinox" has two meanings: first, day and night are equal - on Autumn Equinox day, the sun directly illuminates the equator, making day and night equal in both Northern and Southern hemispheres at 12 hours each; second, climate transitions from hot to cool - Autumn Equinox day is the midpoint of autumn's ninety days, bisecting autumn. After Autumn Equinox, the sun's direct point continues moving from the equator toward the Southern Hemisphere, and locations in the Northern Hemisphere begin experiencing shorter days and longer nights, meaning daylight becomes shorter than nighttime within each day. Autumn Equinox is a special day when day and night are equal length globally. During Autumn Equinox, most regions of China have entered cool autumn, as southward-moving cold air meets gradually weakening warm moist air, producing successive precipitation events and successive temperature drops. As the folk saying goes, it has reached the time of "one autumn rain brings one cold spell."