|
Before the zodiac of twelve there was a division into twenty eight. The Moon is in Pisces tonight, near twenty four degrees, ninety nine percent lit and a day short of full. The older scheme would have placed her differently: not by sign but by mansion, one of twenty eight stations of roughly thirteen degrees, each one marking about a day of her travel.
|
|
The arithmetic is the whole of it. Twelve signs divide the circle by the Sun’s year. Twenty eight mansions divide the same circle by the Moon’s month, which is why a station is a night rather than two and a half days. Versions of the system appear in Arabic, Indian and Chinese astronomy, and the Arabic form is the one that crossed into Europe. Abu Ma’shar, in ninth century Baghdad, and Al-Biruni, in eleventh century Persia, are among the writers who carried it.
|
|
What the mansions were for was timing, and the lists were blunt about it. Travel, marriage, buying, planting, cutting, sending a letter, each attached to a station. That specificity is also the reason the system wants handling with care now: the assignments vary between sources, the boundaries do not line up with the twelve signs, and a confident claim about which mansion she occupies tonight is far easier to make than to defend. The shape of the thing is not in dispute. A calendar of the sky twenty eight nights wide, still running underneath the twelve that everyone was taught.
|
|
