Rahu Kaal for Guwahati

The daylight period — sunrise to sunset — is divided into eight equal parts. Rahu Kaal is one of those parts, and which one depends only on the weekday. Because the day's length changes through the year, so does the window: it is not a fixed 90 minutes, and it is not the same in two cities.

Sunday takes the eighth part, Monday the second, Tuesday the seventh, Wednesday the fifth, Thursday the sixth, Friday the fourth and Saturday the third. Yamaganda and Gulika use the same eight parts with their own weekday patterns, which is why all three shift together.

Rahu Kaal is avoided for starting journeys, signing agreements, beginning new work and conducting ceremonies. Work already under way is not usually interrupted for it.