Celestial Chart

The second of the two rubbings is a Celestial Chart (天文圖 Tianwen tu), which shows a planisphere, or projection of the night sky. Here, each constellation is named and the curved course of the Milky Way is clearly marked. The grouping and naming of stars in China differs from the Greco-Roman constellation names that are more familiar in the West. This chart also uses a traditional Chinese equatorial-polar projection. Three “rings” (带 dai) mark the horizon (outer circle), the celestial equator (the middle concentric circle), and the ecliptic (the middle offset circle). The innermost circle represents the line of constant visibility, enclosing constellations which are always visible in the Northern Hemisphere. Amongst these constellations is the Big Dipper, known as the Seven Stars or Northern Plow in Chinese.

The main text of the Celestial Chart discusses important celestial bodies and their configurations (dimensions and shapes). It also provides observations like relative movements, cycles and durations, relationships to terrestrial phenomena (like the four seasons), and irregular occurrences (eclipses or supernovas). Finally, the chart describes how the fortunes of the people who govern any terrestrial location can be understood by observing that location’s corresponding celestial manifestations.

The epilogue of the 1822 edition of the blue celestial chart specifically references the 1247 dili tu and tianwen tu as models of emulation for the blue maps and charts confirming the source. The main text body of the tianwen tu discusses all important celestial bodies and their configurations (dimensions and shapes), relative movements, cycles and durations, relationships to terrestrial phenomenon (like the four seasons), irregular occurrences (eclipses or supernovas), and how the fortunes of any terrestrial place can be understood by observing its corresponding celestial manifestations.

In the planispere of the tianwen tu, each constellation is named, the curved course of the Milky Way is clearly demarcated and although the text states there are 1565 stars only 1440 stars are shown (fig. ).¹ There are three “circles” or “rings” (dai 带) required to plot the relative positions of celestial bodies, the horizon, the (celestial) equator and the ecliptic (apparent path of the sun against the stars). The tianwen tu uses a traditional Chinese equatorial-polar projection, the inner circle is the line of constant visibility, the equator (chidao 赤道, literally “red road”) is shown as an offset circle within the planisphere while the ecliptic (huangdao 黃道) is the other offset circle intersecting it also within the planisphere, both are labeled as such. The radial lines from the center demarcate the twenty-eight lunar mansions (xiu 宿), each labeled by a character with a ring around it.² And the hour circles of the determinative star of each lunar mansion radiates here as straight lines.

Correlative properties, like those found on the blue chart and astral allocation (fenye) charts in general, can be found on the outer ring of the tianwen tu. The outer ring (horizon) of the tianwen tu is read counterclockwise and indicates numerous directional signifiers such as the widths of the twenty-eight lunar mansions, the twelve terrestrial branches (chen 辰), twelve Jupiter stations or zodiacal positions (muxingci 木星次), names of the ancient states (fen 分) and ancient divisions (ye 野) of China, the later as determined by Yu the Great, that was “governed” by that group of stars. For example, as also found on the blue charts, the section with the “first” branch (chen) zi (at the top of the chart, offset left), is “in the yuanxiao position (ci), ancient state (fen) of Qi, Qingzhou division (ye, today’s Shandong province, fig. ).”³

This type of astrological consideration is found in many cultures from ancient times until today. The example from the tianwen tu confirms that conceptually there is understood to be a direct correlation between the celestial and terrestrial with, localized or grouped according to each lunar mansion as found on the outer ring, spatial coordinates for both presented side by side in the same pie-section division. There is an accepted and understood relational co-existence and correlation between events observed in the sky and events on earth.