Translation of Light
When two planets are not applying to each other directly, a third planet may separate from one and apply to the other, carrying the light from one point to another. The translator-planet acts as an envoy between the two parties of the question.
For a valid translation, the translator must move faster than both main significators, have just separated from one, and be applying to the other.
Planet Positions
Visual
Collection of Light
When two main significators are not applying to each other but both apply to a third, heavier planet, that third planet collects the light of both parties. Collection is not the sign of a messenger carrying light but of an authoritative arbiter who brings the two parties together in their presence.
Planet Positions
Visual
Mutual Reception
If a planet holds one of the essential dignities in the sign where another planet sits, it receives that planet. Mutual reception goes both ways; two planets sit in each other's dignity. The classical tradition treats reception as an indicator of the direction of intent between planets and the degree to which they will treat each other kindly.
The five essential dignities determine the strength of reception in order: own house (+5), exaltation (+4), triplicity (+3), bound (+2), face (+1). Detriment and fall are negative reception — signs of hostility or refusal.
Planet Positions
Visual
Engelleme ve Frustration
When two significators are applying to each other but a third planet steps between them and joins one before the other, the aspect cannot complete. It is the sign that the expected matter will be disrupted by another person or event.
Planet Positions
Visual
Reflection of Light
When the two main significators are not applying to each other but the Moon applies to both of them, the light is transmitted by reflection. An indirect bridge is built between the two parties through the Moon.
Planet Positions
Visual
Refranation
When two significators are applying and, before the aspect completes, one of them stations and turns retrograde, the aspect is never completed. In the classical tradition, this is one of the rare cases of a definitively negative outcome.
Planet Positions
Visual
Besiegement
If a significator is caught between two malefic planets it is besieged. Whichever way it turns, there is difficulty before it. Being caught between two benefics, in the classical tradition, counts as positive besiegement; both sides compete to offer gifts to the person.
Planet Positions
Visual
Partile and Platic Aspects
An aspect is called "partile" when both planets share the same degree number. In the classical tradition this is read as the strongest, most perfected moment of the aspect. An aspect that does not share the same degree but stays within orb is "platic" — effective, but less intense than partile.
Planet Positions
Visual
Antiscia — Shadow Degrees
Every degree of the zodiac has a symmetrical counterpart on the axis through 0° Cancer and 0° Capricorn — the "antiscion," or shadow degree. The classical tradition treats conjunctions and oppositions formed by antiscia with the same strength as bodily aspects.
Planet Positions
Visual
Question Radicality
In the classical horary tradition, not every question is answered. Bonatti and Lilly teach that before judging a chart, one must test whether the question is radical (valid, sincere, and fit to be read). If it is not radical, the chart may mislead.
The checks below scan the chart computed in the "Question Details" panel, so first press Calculate Chart. Five classical criteria — concordance of hour lord / ASC lord, early/late ASC, Void of Course Moon, Saturn in the 7th, Moon combust — are evaluated in order.
First press the "Calculate Chart" button above; the radicality test then runs automatically.
Systematic Introduction to Horary Astrology
An introduction to the classical Lilly–Bonatti technique — video lessons covering core concepts, case examples, and live workshop opportunities. Free registration.
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Frequently Asked Questions
What is horary astrology?
Horary (question astrology) is the branch of classical astrology that reads the answer to a question from the chart cast at the moment the question was asked. Birth time is not required; only the time, place, and sincere intent of the question. William Lilly's Christian Astrology (1647) is the most comprehensive source. Its traditional roots trace to the Hellenistic-Arabic tradition of Antioch and Baghdad — Sahl ibn Bishr, Mashallah, and Guido Bonatti are key authorities.
What is the Regiomontanus house system, and why is it preferred in horary?
The Regiomontanus house system is the mathematical house division method of the 15th-century German astronomer Johannes Müller (Regiomontanus). It divides the celestial equator into 12 equal 30° segments; each division point is projected to the ecliptic via great circles through the north and south points of the horizon to find the house cusps. The classical English horary tradition, led by William Lilly, accepts this system as standard. This tool also uses Regiomontanus.
How does Lilly's 5° rule work?
If a planet is within 5 degrees of the next house cusp, in horary interpretation it counts in the next house. For example, Saturn at the end of the 4th house, 3° from the 5th cusp, is functionally evaluated in the 5th; in a question about children, Saturn's 5th-house meaning comes into play. This tool applies the 5° rule automatically and marks affected planets with a "5° → N" badge.
What are derived houses, and what are they used for?
In classical horary, to read the chart of a topic itself, that topic's cusp is taken as the new ASC. For instance, for a sibling the natal 3rd house is derived; that person's money becomes the natal 4th house (3 + 2 − 1), their partner the natal 9th house (3 + 7 − 1). The "House-Based Calculation" module in this tool automatically computes 12 derived cusps and Arabic parts from any house.
How are essential dignities scored?
Classical Lilly scoring: Rulership (own house) +5, Exaltation +4, Triplicity +3 (varies by diurnal/nocturnal sect; participating +2), Bound (Term, Ptolemy) +2, Face (Decan, Chaldean) +1. Negative: Detriment −5, Fall −4. A total of +5 or above means the significator is strong; negative means peregrine or weak.
Which classical horary techniques does this tool include?
Nine classical techniques: translation of light, collection of light, mutual reception, prohibition and frustration, reflection, refranation, besiegement, partile and platic aspect distinction, antiscia (shadow degrees). Each module works in both slider-demo and chart modes; you can experiment with real significators or abstract configurations.
What does the question-radicality evaluator check?
It automatically scans the five radicality criteria of the classical Lilly–Bonatti tradition: (1) is the Ascendant lord the same planet or same element as the hour lord, (2) is the Ascendant at the beginning (≤3°) or end (≥27°) of its sign, (3) is the Moon Void of Course (VOC), (4) is Saturn in the 7th house (warning that the astrologer may err), (5) is the Moon combust (within 8°30' of the Sun)? Result: Radical / Be Cautious / Not Radical.
How is the planetary hour calculated?
The day is divided from sunrise to sunset into 12 equal "day hours" and from sunset to the next sunrise into 12 equal "night hours" — so an hour's length varies by season. The lord of each hour is set by the Chaldean order: ♄ Saturn → ♃ Jupiter → ♂ Mars → ☉ Sun → ♀ Venus → ☿ Mercury → ☽ Moon. The first hour of the day belongs to the lord of the day (Sunday→Sun, Monday→Moon, Tuesday→Mars, Wednesday→Mercury, Thursday→Jupiter, Friday→Venus, Saturday→Saturn). This tool computes actual sunrise/sunset astronomically.
Which Arabic parts (Pars) are calculated?
Always Fortune (Pars Fortunae) and Spirit (Pars Spiritus); depending on the question category, the parts of Marriage, Love (Eros), Children, Illness, Death, Theft, Travel, Lawsuits, Enemies, Father, Mother, Siblings, Friends, Property, Profession. All formulas adapt to the day/night sect. Additionally, the House-Based Calculation module lets you take any house as the derived ASC and recompute the lots.