Secondary progression — Astrology glossary

Secondary progression is a symbolic timing technique that advances the natal chart using the formula one day equals one year. To see the chart for someone's thirtieth year, an astrologer reads the sky as it actually looked thirty days after birth. Because the inner planets move noticeably day to day, progressions track slow internal development rather than external events. The progressed Moon, the fastest, changes sign every two to three years and is watched closely. In a natal chart's interpretation, progressions matter as a measure of psychological maturation over a lifetime. For example, when someone's progressed Sun changes sign, often once or twice in a life, the shift is read as a gradual reorientation of identity and priorities unfolding over the surrounding years.