The beginning of autumn starts at 09:06:03 on August 7, 2020, and ends on August 22, 2020, 23:44, Saturday.

Rural elders often say, "The summer solstice begins with three gengs and the number of heads falls." The "Geng" here refers to Geng Day, and there are 10 days between each Geng Day.

This means that the third Geng day of the summer solstice among the 24 solar terms is the date of the middle volts of the Dog Days. A Geng day is the starting date of the last period.

Both the first and last days are 10 days, but in some years the middle days are 10 days, and in some years they are 20 days. It mainly depends on whether the Fifth Geng is before or after the Beginning of Autumn. If the fifth Geng day is before the Beginning of Autumn, then the first Geng day after the Beginning of Autumn is the time when the last fall occurs, which means that the middle fall is 20 days.