Qiufen, or Autumn Equinox, is the sixteenth solar term among the 24 solar terms, typically occurring on September 22, 23, or 24 each year. It is one of the earliest established solar terms in ancient China. From this day forward, daylight gradually shortens while night lengthens. 

Meteorological conditions 

Qiufen represents a balance of yin and yang, perfectly aligning with the pursuit of harmony in Chinese culture. At this time, the heat of summer recedes, while the chill of winter has not yet arrived, making it one of the most suitable seasons of the year. According to the 24 solar terms, this day marks the midpoint of the 90 days of autumn, which is also the origin of the name "Qiufen (Autumn Equinox)."

Cultural significance 

Autumn Moon Worshipping Festival: There is an ancient saying, "Spring worships the sun, and autumn worships the moon." Qiufen was traditionally celebrated as a "Moon Worshipping Festival". The current Mid-Autumn Festival is derived from this traditional Moon Festival.

Egg standing: "Qiufen arrives, and the egg stands tall." On Chunfen and Qiufen each year, many people across China participate in the "egg standing" attempts. 

Health tips 

After Qiufen, the yang energy in nature gradually declines, while yin and cold increase, which can have a significant impact on the human body. A slight carelessness can lead to colds, and many chronic ailments may recur. Therefore, it’s essential to pay special attention to diet and to prevent autumn dryness.