河南登封观星台（资料图片） 0:00 人们常说"立竿见影"，用来比喻措施或行动收效迅速。其实，这个成语的本义与中国古人对日影的观测 有关——在阳光下竖起竹竿，即显现影子。从这个简单的现象出发，古人创造出一种精妙的天文仪器： 圭表。它不仅见证了中国人对科学探索的孜孜以求，也体现了中华文明天人合一的宇宙观。 度量时间 在没有时钟的远古时代，中华先民将星空视为永恒的"天钟"。在漫长的岁月中，他们发现，日月星辰的 运转，是有规律且周而复始的。其中，日影的长短与寒暑变化息息相关——夏季正午，日头高悬，树影 短促；冬季正午，太阳低垂，影子拉得很长。这种对影长的直观感受，促使人们开始系统地观测日影， 自然就产生了立竿测影的方法。 "日影的变化，反映的是太阳在天空中位置的变化。当先民们开始尝试度量时间，天空中最明显、且规 律运行的天体——太阳，便成为参考对象。但是人们无法用双眼直接观察太阳，他们发现太阳影子随时 间变化的规律，于是最初的圭表便应运而生，这也是中国最古老的天文测量仪器之一。"北京天文馆古 天文研究中心副主任、副研究员杨帆说。 圭表一般由"圭"和"表"两个部件组成。水平南北方向放置于地面，表面刻有刻度以测量影长的 ...

Core Insights - The article emphasizes the continuous and evolving nature of Chinese civilization, highlighting archaeological discoveries that reflect the early concepts of "China" and its cultural significance [2][3][5]. Group 1: Archaeological Discoveries - The Shanxi Xiangfen Taosi site has yielded the earliest known astronomical instrument, the gnomon, dating back approximately 4,300 to 4,000 years, showcasing early Chinese civilization's understanding of time and space [3][4]. - The Henan Yanshi Erlitou site is noted for the discovery of a turquoise dragon-shaped artifact, which is considered a significant representation of early Chinese royal power and craftsmanship, dating back around 3,800 to 3,500 years [6][7][8]. - The Shaanxi Baoji He Zun, a bronze ritual vessel from the early Western Zhou period, contains the earliest known written record of the term "China," indicating the political and cultural significance of the term during that era [9][10]. Group 2: Cultural Significance - The concept of "China" evolved from a geographical notion to a cultural identity, as seen in the inscriptions and artifacts that reflect the integration of various cultural elements during the Zhou dynasty [10][11]. - The Hubei Wuhan Museum's Five-Breasted Divine Beast Mirror features the phrase "Chinese people," marking it as one of the earliest known instances of this term in physical artifacts, reflecting societal values and aspirations during the Han dynasty [13][14]. - The Xinjiang "Five Stars" woven armguard, discovered in the Niya site, illustrates the historical interactions and cultural exchanges among different ethnic groups in ancient China, emphasizing the unity and diversity of the Chinese civilization [15][16][17].

Core Insights - The article discusses the significance of the summer solstice in ancient Chinese civilization, highlighting its historical and astronomical importance as one of the earliest recorded solar events in China [1][3][12] Group 1: Historical Significance - The Taosi site is recognized as a key archaeological site for understanding the origins of Chinese civilization, alongside other significant sites like Liangzhu and Erlitou [1] - The ancient people of Taosi developed a solar calendar, marking the summer solstice as a crucial agricultural time marker [3][6] Group 2: Astronomical Observations - The Taosi astronomical observatory, with a radius of 10.5 meters and 12 observation slits, allowed ancient inhabitants to accurately track celestial movements and define 20 solar terms, which are foundational to the traditional 24 solar terms [3] - The use of a gnomon and a horizontal measuring stick (known as a "gui") complemented the observatory, enabling precise measurements of shadow lengths to establish a solar calendar [6] Group 3: Cultural Practices - The article describes how ancient people observed natural phenomena, such as the shedding of deer antlers and the emergence of cicadas, to mark seasonal changes and agricultural practices [8][10][12] - The concept of "half summer" is introduced, referring to a medicinal plant that grows during this period, symbolizing the transition of seasons and the balance of yin and yang [12]