What Are the Lunar Mansions?
The Lunar Mansions (宿, Xiù) are 28 sectors of the sky mapped by ancient Chinese astronomers along the ecliptic. Each mansion corresponds roughly to the Moon's one-day 'station' during its journey across the sky — hence the name. The system is over 2,000 years old and was used for both astronomical and astrological purposes: weather prediction, agricultural planning, selection of auspicious dates and the interpretation of dreams. The Lunar Mansions are part of the Tong Shu almanac — each day has an assigned Mansion that adds another layer to the interpretation of the day's quality. Similar systems exist in Hindu astronomy (Nakshatras) and Arabic astronomy (Manazil), suggesting independent discovery of this structure by different civilisations.
Four Groups — Four Celestial Creatures
The 28 Mansions are divided into four groups of 7, each assigned to one of the Four Celestial Creatures (四象, Sì Xiàng). Azure Dragon (青龍, Qīng Lóng) — eastern quarter of the sky, 7 mansions: Jiao, Kang, Di, Fang, Xin, Wei, Ji. Associated with spring and the Wood element. White Tiger (白虎, Bái Hǔ) — western quarter, 7 mansions: Kui, Lou, Wei, Mao, Bi, Zi, Shen. Associated with autumn and the Metal element. Black Tortoise (玄武, Xuán Wǔ) — northern quarter, 7 mansions: Dou, Niu, Nü, Xu, Wei, Shi, Bi. Associated with winter and the Water element. Vermilion Phoenix (朱雀, Zhū Què) — southern quarter, 7 mansions: Jing, Gui, Liu, Xing, Zhang, Yi, Zhen. Associated with summer and the Fire element.
Dragon's Mansions — Eastern Quarter
The seven Mansions of the Azure Dragon (Jiao through Ji) cover constellations viewed from the east. They are associated with spring energy, growth and new initiatives. Mansion Jiao (角, 'Horn') — inauguration, auspicious for new beginnings. Mansion Kang (亢, 'Neck') — caution required, a day demanding attentiveness. Mansion Di (氐, 'Root') — stabilisation, good for long-term planning and foundations. Mansion Fang (房, 'Room') — harmony and peace, favourable for relationships. Mansion Xin (心, 'Heart') — intensity, a day of strong emotions. Mansion Wei (尾, 'Tail') — expansion, favourable for enterprises. Mansion Ji (箕, 'Basket') — cleansing, good for tidying and eliminating what is superfluous.
Tiger's and Phoenix's Mansions
Seven Mansions of the White Tiger (Kui through Shen) — western quarter, autumn, Metal. Mansion Kui (奎) is linked to literature and the arts. Mansion Lou (娄) favours gathering resources. Mansion Wei (胃) — good for meals and accumulation. Mansion Mao (昴) — intensity, a day requiring focus. Mansion Bi (毕) — rain and agriculture, favours 'wet' activities. Mansion Zi (觜) — speech and communication. Mansion Shen (参) — valour and determination. Seven Mansions of the Vermilion Phoenix (Jing through Zhen) — south, summer, Fire — linked to administration, ceremony and authority. Mansion Jing (井, 'Well') — access to resources. Mansion Gui (鬼, 'Ghost') — death and ancestors, a day of reflection on impermanence.
Tortoise's Mansions — Northern Quarter
Seven Mansions of the Black Tortoise (Dou through Bi) cover northern constellations. They are associated with winter, rest and depth. Mansion Dou (斗, 'Dipper') — planning and calculation. Mansion Niu (牛, 'Ox') — work and perseverance. Mansion Nü (女, 'Woman') — craftsmanship and attention to detail. Mansion Xu (虚, 'Emptiness') — reflection and meditation. Mansion Wei (危, 'Danger') — caution; avoid risky actions. Mansion Shi (室, 'Room/Chamber') — construction and shelter. Mansion Bi (壁, 'Wall') — protection and boundaries, good for building walls and security measures. The Tortoise's Mansions often have a calmer character, favouring inner focus over outward activity.
Lunar Mansions in Tong Shu
In the Tong Shu almanac every day has an assigned Lunar Mansion that adds another layer to the interpretation. Each of the 28 Mansions has a list of "favourable" (宜) and "prohibited" (忌) activities. For example: on the day of Mansion Jiao (角), prayer, gardening and agriculture are favourable; on the day of Mansion Shen (参), military actions and determined effort are favourable. These recommendations are specific and detailed, going beyond the general Officer rating. Combining the Day Officer + Lunar Mansion + Year and Month Breakers creates the full "profile" of a day in the classical Tong Shu. Advanced practitioners consider all these layers when selecting an auspicious date.
Astronomical and Cultural Context
The 28 Mansions system reflects actual star clusters visible from China, chosen to divide the ecliptic evenly. They are not equal-width sectors — the size of each Mansion corresponds to the actual angular extent of its constellation in the sky. This system was used in Chinese imperial astronomy to track the movements of planets, which had significance for state prophecy. Evidence of the Lunar Mansions system has been found from the Shang era (c. 1200 BCE) — making it one of the world's oldest astronomical-astrological systems. Today the Mansions are used mainly by advanced Feng Shui and Ba Zi practitioners, rather than in mainstream popularisation.