How are secondary progressions calculated?

Each day after birth symbolically represents one year of life. At age 30, the progressed planets use their real positions about 30 days after birth.

How is this different from Solar Arc?

In secondary progressions every planet moves at its own real rate. Solar Arc moves every planet and angle by the same progressed-Sun arc.

What should I read first?

Start with the Progressed Moon sign, natal house, and lunar phase. Then check progressed Sun and personal-planet contacts to natal points.

Predictive astrology · Day for a year

Secondary Progressions

See how each planet has progressed at its own day-for-a-year speed, with the Progressed Moon, sign changes, and natal contacts brought into focus.

Method

One ephemeris day represents one year of life

Primary signal

Progressed Moon sign, natal house, and lunar phase

Timing layer

Progressed-to-natal contacts with tight orbs

Progressed chart calculation

Choose the natal chart and target date

Exact birth time grounds natal houses and progressed angles. Every planet then advances by its own real ephemeris motion.

Natal chart

Birth data

Date of birth

Time of birth (Local time)

Birth city

Choose a city from the suggestions for coordinates.

Progression date

Target date

Choose any date after birth. Today is selected by default.

Calculation method

Secondary day-for-year · Solar Arc angles · Natal Placidus houses

Use an exact birth time for reliable house and angle context.

Secondary Progressions guide

Review the day-for-a-year method before opening the progressed chart.

What this calculator prioritizes

The Progressed Moon leads because it changes fastest and describes shorter internal chapters. Progressed Sun, Mercury, Venus, Mars, angles, sign changes, and station changes provide the slower structural layer.

How to read progressions

Look for repetition. A progressed contact becomes more useful when the same natal planet, angle, or house is activated elsewhere. Progressions describe an unfolding pattern; transits and returns can help sharpen external timing.