Sidereal and tropical zodiacs

Sidereal and tropical zodiacs both divide a circle into twelve equal 30° signs. They differ in where that circle begins.

The tropical zodiac begins at the March equinox. A sidereal zodiac fixes its reference relative to the stellar background through a chosen ayanamsa. Precession changes the relationship between these references over time.

Signs are not constellation outlines

An astronomical constellation occupies an irregular region of sky. A zodiac sign is an equal angular sector. “The Sun is in a sidereal sign” therefore does not mean that every boundary matches the modern astronomical constellation of the same name.

The difference between the two zodiac references is not a timeless fixed number. A useful numerical comparison must state its date and the sidereal reference used.

What panchang.now shows

The Kundli displays sidereal signs. Its ayanamsa selector offers three reference choices. Changing chart layout from North to South Indian does not change the zodiac.

A tropical Sun-sign calendar may give a different sign from the Sun row here. Compare the actual birth moment and zodiac reference instead of replacing a sign solely from a date-range list.

Signs and houses remain distinct in either system. The signs versus houses guide explains their separate roles. Choosing a coordinate convention specifies how a chart is read; it does not itself demonstrate a predictive effect.

See the chart and its tables on the Kundli page.