How long is beginning of autumn?

According to the calendar query, today is September 6, 2023, and beginning of autumn in 2023 is August 8, 29 days have passed since beginning of autumn. Beginning of autumn is the 13th solar term in the "Twenty-four Solar Terms" and the beginning of autumn, which is celebrated on August 7th or 8th of the Gregorian calendar every year. "Reason" means the beginning; "Autumn" means that the grain is ripe. The change of the whole nature is a step-by-step process, and beginning of autumn is a turning point in which the Yang gradually closes, the Yin gradually grows, and the Yang gradually gets cloudy.