Also known as “Magickal Hours,” a division of the day and night into sections ruled by the energies of the planets. To determine the length of each planetary hour, divide the daylight hours by 12. They will be different in length than the night hours (to discover the length of which you divide the total time of darkness into 12 equal periods) except on the equinoxes when the planetary hours are all sixty minutes in length. Used for selecting the optimum time to perform a magickal ritual.