The Twenty-Four Solar Terms
The 24 solar terms are the 24 days in the Chinese calendar that indicate the seasonal division points and movement of the natural cycle. The ancient Chinese divided a year into four seasons – spring, summer, autumn, and winter, each lasting three months and each month having two solar terms, which make up 24 terms for the whole year. The 24 solar terms are: Beginning of Spring, Rain Water, Awakening of Insects, Spring Equinox, Pure Brightness, Grain Rain, Beginning of Summer, Grain Budding, Grain in Ear, Summer Solstice, Slight Heat, Great Heat, Beginning of Autumn, End of Heat, White Dew, Autumn Equinox, Cold Dew, Frost's Descent, Beginning of Winter, Light Snow, Heavy Snow, Winter Solstice, Slight Cold, and Great Cold. Each term denotes a natural phenomenon with phenological meanings.
The 24 solar terms were created in the Yellow River basin and have been in use for more than 2,000 years since the Western Zhou Dynasty (1046-771 BC). The Astronomical Observatory in Dengfeng, Henan Province is a direct proof of China's invention of the 24 solar terms, as its Sky Measuring Scale, which has a history of 700 years, is a device used to measure the shadow cast by the sun at noon and consequently determine when a solar term falls and how many days a year has. The observatory was built under the direction of Guo Shoujing, a renowned astronomer in the Yuan Dynasty. Guo used it to accurately identify the 24 solar terms and direct the farming and daily routines.
The 24 solar terms constitute not only a system of seasonal changes that guides farming, but also a cultural system involving a diversity of folklore and customs. As a major part of the fine traditional Chinese culture, they have been introduced to the Korean Peninsular, Japan, Vietnam, and other places and exerted positive effects on their agrarian production and social and cultural development. In November 2016, the 24 solar terms were inscribed on the UNESCO's Representative List of the Intangible Cultural Heritage of Humanity.
二十四節氣
二十四節氣是中國歷法中表示自然節律變化的特定節令。中國古人將一歲分為四時，即春、夏、秋、冬各3個月，每月2個節氣，一年共有24個節氣：立春、雨水、驚蟄、春分、清明、谷雨、立夏、小滿、芒種、夏至、小暑、大暑、立秋、處暑、白露、秋分、寒露、霜降、立冬、小雪、大雪、冬至、小寒、大寒，每個節氣均有其獨特的含義。
二十四節氣形成于中國黃河流域，自西周開始，至今已沿用2000多年。河南省登封市觀星臺是二十四節氣產生的最直接文物史證，現存有700年歷史的“量天尺”，用來測量正午日影，可定節氣和一年時長。觀星臺由元朝著名天文學家郭守敬主持建造，他在此準確地測定出一年中有二十四個節氣，用以指導生產生活。
二十四節氣不僅是指導農耕生產的時節體系，更是包含豐富民俗事象的文化系統。作為中華優秀傳統文化的重要組成部分，二十四節氣曾傳播到朝鮮、日本、越南等國家，對當地農耕生產和社會文化發展產生了積極影響。2016年11月，二十四節氣被列入聯合國教科文組織“人類非物質文化遺產代表作名錄”。
