Flying Stars (Xuan Kong Fei Xing)
San Yuan feng shui; systematized in Shen Zhureng's Shen Shi Xuan Kong Xue (Qing dynasty)
Flying Star feng shui maps the nine stars of the Luoshu magic square onto a building from two facts: the compass direction it faces and the 20-year period of its completion. The San Yuan time cycle — nine periods of twenty years, anchored so that Period 9 runs 2024–2043 from Li Chun to Li Chun — and the flight of the stars around the square are fully deterministic; the method reached its standard written form in Shen Zhureng's Qing-era compendium.
What it measures
Three number layers per palace of the floor plan: the base (period) star flown forward, and the mountain and water stars flown forward or reverse according to the yin/yang of the facing and sitting mountains among the 24. Where the period's own star lands classifies the chart (wang shan wang shui, double-at-facing, and so on).
Where practitioners disagree
- What happens when the facing is off the mountain's midline?
The substitute-star (替卦) schools chart such facings differently — and disagree with each other on the trigger, the table and the star-5 case
The disagreement is genuine and school-level.
This engine: The standard 下卦 chart is always computed, and out-of-center or void-line facings are flagged with the convention stated.
Sources
- Shen Zhureng, 沈氏玄空學 (Shen's Xuan Kong Study) (Qing dynasty)