Solar arc directions move every natal planet and angle by one increment: the distance the Sun has traveled in the day-for-a-year progressed moment. When a directed planet reaches a natal planet or angle — especially by conjunction or square — the period around exactitude is a turning point in the chart.
PathFinder Charts computes that increment from a natal chart and a real ephemeris. This page is how the engine does it. It is not a birthday widget, and it does not invent aspect dates.
A full solar arc chart needs natal longitudes for every planet and angle, then the Sun's position at a progressed moment. That moment is the birth instant advanced by one day per year of life. The engine measures how far the Sun has moved and applies that same arc to the rest of the chart.
A birth date alone cannot produce those longitudes. A few minutes of birth-time error moves the Ascendant and Midheaven, and solar arc aspects to those angles shift by about a year for every four minutes. That is why this page does not ask for a birthday and then print a directed chart.
The increment people quote — age N ≈ N degrees — is labeled below as the increment, not as a chart. To run the technique, open the app and cast it on a natal chart. Solar arc directions are PathFinder+.
The engine uses the same day-for-a-year ratio as secondary progressions. Elapsed life in days is divided by 365.25. That number of days is added to the birth instant — or subtracted for converse. The Sun's ecliptic longitude at that progressed moment minus the natal Sun longitude is the solar arc.
That single increment is then added to every natal planet, every house cusp, the Ascendant, and the Midheaven. Directed points move at the Sun's rate. None of them retrograde. The engine then computes aspects from the directed planets to the natal planets and to the natal Ascendant and Midheaven.
This is not the Naibod key — a fixed 59′08″ per year. It is not a flat 1° per year. It is the Sun's actual travel in the progressed moment. The Sun moves faster near perihelion and slower near aphelion, roughly 0.953° to 1.019° per day. At age 60 the gap between a constant 1°/year and the true increment can reach about 2°. The wiki's "1° per year" is the shorthand. The code measures the Sun.
In the app you pick a target date and a direction — direct or converse. The wheel can stand alone as the directed chart or sit as a bi-wheel against the natal chart. Tabs list directed planets, directed-to-natal aspects, houses, and an AI reading retrieved from the solar-arc library.
A common rule of thumb is age N ≈ N degrees of arc. That number is the increment. It is not a solar arc chart, and PathFinder Charts does not add it as a flat degree.
The engine measures the Sun's actual longitude at the day-for-a-year progressed moment and uses that increment. The true arc is typically just under 1° per year and varies with the Sun's speed. That is why a birthday widget cannot print your directed chart.
The library PathFinder Charts reads from holds 211 solar-arc entries. They focus on conjunction and square: Sun, Moon, Venus, Mars, Jupiter, and Saturn directed to natal planets and angles.
Conjunctions are the stronger contact. With a 1° orb, a solar arc aspect is technically in effect for about two years. In practice the strongest stretch sits within a few months of exact. Conjunctions generally hold within six to nine months of exact, unless a timing marker — often the secondary progressed Moon — extends the window.
When any of the Four Primaries — Sun, Moon, Ascendant, Midheaven — conjoin each other by solar arc, the Method treats that as a Superconjunction. The orb widens to at least 3°. Those contacts are rare. Most charts have few; some have none. They mark the largest structural turns the technique can show.
Saturn directed to a natal planet is framed as a confrontation with responsibility. Jupiter directed to a natal planet is framed as expansion. The tone comes from the two planets and from the natal aspect between them, if one exists. A natal square pre-loads even a later directed trine. A natal trine protects a later directed square. Solar arcs fulfill natal promises. They do not rewrite them.
Both techniques start from the day-for-a-year ratio. They are not the same technique.
Secondary progressions move each planet at its own speed. The progressed Moon changes sign every two and a half years. Outer planets barely move. When an outer planet finally perfects a progressed aspect, that contact is unusually strong — the Method's Invisible Elephant.
Solar arc directions take only the Sun's travel and apply it uniformly. Jupiter, Saturn, Uranus, Neptune, and Pluto all move at the Sun's rate. There is no Invisible Elephant effect, because nothing is crawling. The trade-off is a clean yearly increment: any directed planet can reach any natal point.
PathFinder Charts computes both. The progressions page is the day-for-a-year interior chart. This page is the uniform direction.
Solar arc directions are one of the Pathfinder Method's Seven Data Sets. They sit in the Upper Tier with secondary progressions and outer-planet transits — dated aspect lists, not return charts. The Method runs them in both direct and converse motion, then collates the hits with progressions into one timed list.
They are not interchangeable with annual profections or zodiacal releasing. Those are Hellenistic time-lord techniques. Profections activate one house per year. Zodiacal releasing divides a life into peak and quiet chapters. Solar arcs date turning-point aspects.
Those belong to a timed natal chart and an ephemeris. PathFinder Charts runs them there.
The free tier includes the natal chart, daily transits, annual profections, three birth profiles, and two AI mini-readings a day. No card. PathFinder+ is $9.99 a month or $79.99 a year, with a 7-day trial on annual billing, and adds the rest of the thirteen chart types — including solar arc directions.
In the app the same calculator uses the day-for-a-year progressed Sun, applies that increment to every natal point, and lists directed-to-natal aspects. Positions come from a real astronomical ephemeris validated against JPL Horizons. Interpretation uses retrieval-augmented generation over a curated library. Primary application servers sit with Hetzner in Falkenstein, Germany.
The sibling technique is the secondary progressions guide — same ratio, different motion. The free yearly house count is the annual profections calculator. Zodiacal releasing is the Hellenistic chapter frame. For the wider stack, start with what predictive astrology is. The glossary entry is the short definition. If you are deciding whether to move tools, the switching guides state what PathFinder computes and what it costs.
Solar arc directions are PathFinder+. The free tier still includes the natal chart, daily transits, and annual profections.