When is the Millennium in the twenty-four solar terms?

Millennium is the fifteenth solar term in the "twenty-four solar terms", which is the end of applying for the moon and the beginning of the unitary month in the calendar. When the sun reaches 165 degrees, it will cross the Gregorian calendar on September 7-9. After the Millennium solar terms, the yin and cold qi rises, the summer heat residual temperature in early autumn gradually dissipates, cold and hot alternate day and night, and the cold produces dew condensation. The ancients used four seasons to match five elements. Autumn belongs to gold, gold and white alternate with each other, and autumn dew is described in white, hence the name "White Dew".