Sidereal Zodiac

The zodiac Vedic astrology uses, fixed to the positions of the stars rather than to the seasons. It is the same sky as the tropical zodiac, numbered from a star-based zero point instead of the spring equinox.

A zodiac is just a way of numbering the ecliptic — the band the Sun and planets travel through — into twelve 30° signs. The question is where 0° Aries sits. The tropical zodiac, used in Western astrology, puts it at the spring equinox, so the signs track the seasons. The sidereal zodiac, used in Vedic astrology, fixes it to the stars, so the signs stay aligned with the constellations over long spans of time. Because the equinox drifts against the stars (precession), the two zodiacs have separated by roughly 24° over the last two millennia. That offset is the ayanamsa. Convert one to the other by subtracting it — the planets don't move, the ruler just starts counting from a different place. A chart that reads late Leo tropically may read early Leo or late Cancer sidereally. Both zodiacs describe the same observable sky. Which frame is 'right' is a question of tradition and purpose, not of astronomy: the positions are identical measurements expressed two ways.

Not: The sidereal zodiac is not a claim that the constellations physically influence you any more than the tropical one does. It is a different anchoring convention for the same twelve-fold division of the ecliptic. It is also not the same as the visible constellations, which are unequal in size.

The choice between tropical and sidereal is a convention, not a finding. Neither has been shown to track outcomes; this reading shows both so the difference is visible rather than hidden.