Working and Living by the Sun

The Connotations

As early as the Spring and Autumn Period (770 - 476 BC), ancient people established the first four solar terms to signify vernal equinox, mid-summer, autumnal equinox, and mid-winter. The 24 solar terms were finalized in 104 BC when the Taichu Calendar was established, the first complete written calendar in Chinese history. In this calendar, the astronomical positions of the 24 solar terms were confirmed.

 

The 24 solar terms reflect the changes in celestial phenomena, climate, precipitation, and phenological sequence in time. Originating in the Yellow River basin, one of the cradles of Chinese civilization, the system gradually spread across the country. In a typical agricultural society like ancient China, the 24 solar terms were a marker against which people could arrange farming work and social activities like festivals and even a family’s daily life.

As the solar terms are based on the sun’s position in the zodiac, they have basically fixed corresponding dates in the Gregorian Calendar – in the first half year most fall on the 6th or 21st days of the month, and in the second half, on the 8th or 23rd days, with minor variations of within one or two days.