File:Soochow Planisphere Detail.jpg

English: A rubbing of the "Soochow Planisphere" or "Suzhou Planisphere" (Tianwentu), a chart of the stars in the sky from the north celestial pole to 55° S. A central circle bounds the circumpolar constellations, outside of which the sky is divided into the 28 mansions (xiu) marking the longitude along the ecliptic of the moon through a sidereal month. Each 7 mansions are associated with a separate direction, color, and symbol (Verdant Dragon, Black Tortoise, White Tiger, Vermilion Phoenix) with various additional associations from the 5 element (wuxing) and fengshui systems. The overlapping outer circles are the celestial equator ("Red Road") and the ecliptic ("Yellow Road"). The band curving through the chart is the Milky Way ("River of Heaven"). The explanatory text states that 1565 stars were known to the Song-era astronomers but only 1440 are depicted. It also relates that the Great Absolute (Taiji) unfolded with the light and pure forming Heaven/Spirit, the heavy and impure forming Earth/Matter/Body, and the mingled pure and impure forming Man. This was presumably intended as a tutoring aid for Huang Shang as he educated the future Ningzong Emperor of the Song. Huang Shang drafted this map with several others at some point between 1190 and 1193, formally presenting them to either the Guangzong or Ningzong Emperor c. 1194. Wang Zhiyuan later engraved them on stone c. 1247 and this rubbing was made at some point during the 16th century, per carbon dating. The original stella is now at the Purple Mountain Observatory in Nanjing, with a copy at the Suzhou Confucian Museum.