Why does beginning of autumn have a few minutes?

Each solar term meets at a different time every year. It can happen in the morning, at noon and at night, at some time of the day.

The solar term of 202 1 beginning of autumn is 2021August 7 14: 53: 48, which falls on Saturday, June 29th of the lunar calendar.

Seasonal division

Astronomical method: The traditional method of dividing the four seasons is based on the change of astronomical phenomena. Beginning of autumn is the starting point of autumn, with four seasons as the starting point. Beginning of autumn is the starting date of autumn according to the astronomical observation position. From beginning of autumn to beginning of winter, the beginning and end of autumn is the result of celestial movement.

Temperature method: At present, the four seasons are often divided according to the temperature change, and the "average temperature" proposed by modern scholar Zhang Baokun is adopted. According to the average temperature method, the average daily temperature for five consecutive days is between 10℃ and 22℃, which is counted as autumn.