Secondary Progressions

Secondary progressions (or "day for a year" progressions) are a common Western timing technique: one day of ephemeris movement after birth is read as one year of life. So the progressed Moon moves roughly one degree per month, and the progressed Sun about one degree per year. They are useful for "when" questions—when a theme might peak or when inner readiness meets outer opportunity. They differ from transits (actual sky now) and from Vedic dashas (planetary periods). Calculating progressions requires the same precise ephemeris (e.g. NASA DE441) used for the natal chart; the date used is birth date plus years (and fraction) of life.