Arabic Parts How It Works

The Lot Formula

Every Lot follows the same structure: Lot = Ascendant + Planet A - Planet B, normalized to 0-360 degrees. The result projects the longitudinal distance between two planets onto the Ascendant, turning a relationship between two chart positions into a single new sensitive point.

Day/Night Reversal

A handful of Lots, the Part of Fortune and the Part of Spirit, reverse their formula depending on whether the Sun sits above or below the horizon at birth. In a day chart (Sun in houses 7-12), the standard formula applies. In a night chart (Sun in houses 1-6), Planet A and Planet B swap places. Most other Lots use a single fixed formula regardless of day or night.

Reading a Lot

Once calculated, a Lot is read like any other chart point: by the sign it falls in and the house it occupies. The sign colors how its theme expresses, while the house shows which life area that theme is most active in.