Why house systems disagree

The explanation

Here is an honest wrinkle: astrologers do not all draw the house lines the same way. Placidus splits the houses by the time it takes points to rise; whole-sign gives each house one full sign; equal houses uses even thirty-degree slices. Because the methods cut the circle differently, a planet near a house edge can land in, say, the ninth in one system and the tenth in another. None of this touches the astronomy — the planet's real position is fixed and computed; only the house frame is a modelling choice. Sneba lets you pick the system, so you can see how the reading shifts. Treat it as a lens you get to set, not a single right answer handed down.