Planetary Hours
The hour has its own ruler.
Planetary hours begin at your local sunrise. See this hour, what comes next, and the full day at your place.
Calculate planetary hours
How planetary hours work
The astrological day begins at sunrise. Daylight is divided into twelve equal planetary hours, and the night into twelve more, however long they are on the clock. The ruler of the day starts the sequence; the seven traditional planets then repeat in the Chaldean order: Saturn, Jupiter, Mars, Sun, Venus, Mercury and Moon.
Method: local astronomical sunrise and sunset, with twelve unequal day hours and twelve unequal night hours. Rulers follow the traditional Chaldean order from the ruler of the planetary day.
A quick example
If sunrise is 06:00 and sunset is 18:00, each day hour lasts sixty minutes. In summer or winter, daylight hours expand or contract, so the planetary hour may be longer or shorter than a clock hour.
What this does and does not tell you
- The answer is specific to the chosen place and date. A different longitude, season or time zone can change the hour.
- A planetary hour is one traditional timing factor, not a promise that an undertaking will succeed. Electional judgment considers the whole chart.
- At high latitudes, some dates have no sunrise or sunset. The calculator says unavailable rather than inventing a conventional answer.
Common questions
Do I need my birth time?
No. Planetary hours are calculated for a place and a moment, not from a natal chart.
Why is this not the same as a clock hour?
Each daylight period is divided into twelve equal parts and each night into twelve equal parts. Their lengths change with the season and latitude.
What is the Chaldean order?
It is the traditional sequence Saturn, Jupiter, Mars, Sun, Venus, Mercury and Moon. Planetary-hour rulers cycle through this order from the ruler of the day.
Why is there no result for some locations?
The traditional calculation needs a sunrise and a sunset. During polar day or polar night, one or both may not occur, so there is no settled result to report.