What is the first autumn of autumn frost? What does the second autumn mean?

The first autumn means: the beginning of autumn. The second autumn is the autumnal equinox.

The author of Twenty-four solar term song is unknown.

Original text:

The spring rain shakes the spring and clears the valley, and the summer is full of mountains and summers.

Autumn dew, autumn frost, little snow in winter and cold in winter.

The two festivals remain unchanged every month, with a maximum difference of one or two days.

The first half of the year is June 2 1 day, and the second half is August 23.

Extended data:

"Twenty-four solar term song" is a small poem compiled for the convenience of remembering the twenty-four solar terms in the ancient calendar of China, and there are many versions circulating. Twenty-four solar terms is a calendar formulated by China in ancient times to express seasonal changes and guide farming, and it is the crystallization of long-term experience and wisdom of working people in ancient China.

Twenty-four solar terms scientifically reveal the laws of astronomical and meteorological changes, which not only have a guiding role in agricultural production, but also affect ancient people's food, clothing, housing and transportation, and even cultural concepts. It skillfully combines astronomy, natural rhythm and folk custom, and derives a large number of related seasonal cultures, which has become an important part of China traditional culture.