Sunset closes the daytime span that the panchangam divides into eight equal parts, so it is the second boundary that fixes Rahu Kalam, Yamagandam and Gulika Kalam. It also opens the periods reckoned from dusk — Pradosh Kaal among them — and it is the reference for the night's own divisions.
The day divided in eight
Take the span from sunrise to sunset and divide it into eight equal parts. Each part is one-eighth of the daylight, so its length changes through the year: about 90 minutes near the equinoxes in Hyderabad, longer in summer and shorter in winter. Rahu Kalam, Yamagandam and Gulika Kalam each occupy one of these eight parts, assigned by weekday.
This is why the commonly quoted "Rahu Kalam is 90 minutes" is an approximation rather than a definition. The period is one-eighth of that day's daylight, whatever that happens to be.
The periods sunset opens
Several observances are reckoned forward from sunset rather than from sunrise, and their windows are correspondingly local.
- Pradosh Kaal — roughly the 96 minutes following sunset, when Pradosham is observed on Trayodashi.
- Lakshmi Pooja on Diwali Amavasya, timed within the Pradosh Kaal.
- Nishita kaal — the middle watch of the night, computed between sunset and sunrise, used for Janmashtami and Shivaratri.
- The four jaamas of Maha Shivaratri, dividing sunset to sunrise into four watches.
Where the general rule stops
Any period reckoned from sunset is local to the place it was computed for, in the same way sunrise timings are. A Pradosh or nishita window taken from a calendar printed for another city will be wrong by the difference in sunset between the two.
Every timing on this page is computed for Hyderabad and Indian Standard Time. For a consequential date, confirm the window with the Purohit conducting the ceremony rather than acting on a published table.
Written and reviewed by the AnugrahaSidhi editorial team. Last substantive review: . How we source and correct this material is set out in our editorial policy.