When was the first frost in the 24 solar terms introduced?

1, the first frost, is the eighteenth of the twenty-four solar terms and the last solar term in autumn. Fight with your fingers; The solar calendar is 210; Celebrate every year on Gregorian calendar 10 year1October 23rd-24th. After entering the first solar term in first frost, the scene of late autumn is obvious, and cold air moves southward more and more frequently. The first frost does not mean "frost", but refers to the sudden drop in temperature and the large temperature difference between day and night. On the national average, "first frost" is the season with the largest temperature difference between day and night in a year.

2. In the first frost season, everything ends, everything in the sky ends, the sun goes down to the ground, Yin Qi begins to condense, and the first frost weather gets colder. Because "frost" is a manifestation of cold weather and large temperature difference between day and night, it is named "first frost", which means "sudden drop in temperature and large temperature difference between day and night". The first frost solar terms are characterized by cold weather in the morning and evening, hot weather at noon, large temperature difference between day and night, and obvious autumn dryness.