Planetary hours
As each day is divided into 24 hours, the first hour of a day is ruled by the planet three places down in the Chaldean order from the planet ruling the first hour of the preceding day; i.e. a day with its first hour ruled by the Sun ("Sunday") is followed by a day with its first hour ruled by the Moon ("Monday"), followed by Mars ("Tuesday"), Mercury ("Wednesday"), Jupiter ("Thursday"), Venus ("Friday") and Saturn ("Saturday"), again followed by Sunday, yielding the familiar naming of the days of the week.
Planetary hours-4