Horary Astrology (卜卦占星)

The Astrology of the Question — A Chart Cast for the Moment You Ask

Overview

Horary astrology answers a specific, sincere question by casting a chart for the exact moment and place the question is understood. Unlike a birth chart, which describes a person, a horary chart describes a situation: the rising sign and its ruler stand for you (the querent), the house that matches your question — and its ruler — stand for the thing asked about (the quesited), and the Moon flows between them as a co-significator and barometer of the matter. The astrologer then reads whether the two come together by an applying aspect — directly, or with the help of a third planet 'translating' or 'collecting' their light — to judge whether the matter will come to pass, and roughly when. It is one of the most concrete and testable branches of Western astrology, with a rule-set largely fixed for nearly four centuries.

Origin & history

The horary method used here descends from William Lilly (1602–1681), whose 'Christian Astrology' (1647) was the first major astrology textbook in English and remains the central reference for the craft. Lilly synthesised the medieval Arabic and Latin tradition — Masha'allah, Sahl ibn Bishr, and Guido Bonatti's 'Considerations' — into a systematic, worked-example method for judging questions. The technique was nearly lost in the 20th century until Olivia Barclay drove the 1985 facsimile reprint of Lilly and founded the Qualifying Horary Practitioner course, sparking a revival carried forward by John Frawley, Deborah Houlding, Derek Appleby and Barbara Watters.

Interrogational astrology — answering questions from the chart of the moment — is documented from Hellenistic times and flourished in the medieval Persian and Arabic worlds, where the rules of significators, dignities, reception and perfection were codified. It passed into Latin Europe from the 12th century and reached its English peak with Lilly during the turbulent 1640s. After the Enlightenment it fell from favour, surviving in almanacs, until the late-20th-century traditional revival restored Lilly's exact method. Today practitioners differ chiefly on house system (Regiomontanus, Lilly's choice, versus Placidus), whether the modern outer planets may signify, and how strictly to apply the 'considerations before judgement'. askTIAN follows the traditional Lilly line: seven classical planets, Regiomontanus houses, and the strictures treated as cautions rather than hard prohibitions.

How it works

askTIAN converts the moment you understand the question (date, time, timezone) and your location to a single instant in Universal Time, then computes the sidereal time, Ascendant, Midheaven and the twelve Regiomontanus house cusps with a Meeus-precision ephemeris. It places the seven classical planets, scoring each for essential dignity (domicile +5, exaltation +4, sect-aware triplicity +3, Egyptian term +2, Chaldean face +1; detriment −5, fall −4, peregrine −5) and accidental dignity (Lilly's house-strength table, retrograde, speed, and the cazimi/combust/under-the-beams Sun zones). It assigns your significator (the Ascendant ruler, with the Moon as co-significator) and the quesited's (the topic house's ruler), then tests every aspect between them using moiety orbs and — the heart of horary — whether each aspect is applying or separating, because only an applying aspect can perfect a future matter. Perfection by direct aspect, translation or collection of light yields a yes / qualified / no verdict, with a hedged timing estimate, mutual-reception analysis, void-of-course and via-combusta checks, the classical considerations as flags, and a transparent 0–100 favorability score.

Good for

Use cases

Yes / No Question Oracle

Send the question text, the moment it is asked, and the querent's location. The API returns the querent and quesited significators, every applying/separating aspect between them, the perfection verdict (yes/qualified_yes/qualified_no/no/inconclusive) and a 0–100 favorability score with a per-factor breakdown — everything an app needs to render a reasoned answer rather than a coin-flip.

Topic Routing by House

Pass a topic hint (career, money, marriage, health, travel, children, home…) and the engine maps it to the correct quesited house and ruler, or supply an explicit quesitedHouse to override. This lets a product route free-text questions to the right significator without the user knowing any astrology.

Timing Estimates

When the chart perfects, the response includes a timing estimate derived from the degrees-to-perfection scaled by the sign's mode and the perfecting planet's house — surfaced as a hedged range (days/weeks/months) rather than a false-precise date, for 'when might this happen?' features.

Decision-Support Without a Birth Time

Because a horary chart needs only the question moment — not the querent's birth data — apps can offer meaningful astrological guidance to users who don't know their exact birth time, which a natal-chart product cannot.

Key terms

Querent & Quesited
The querent is the person asking, signified by the ruler of the Ascendant (with the Moon as co-significator). The quesited is the thing asked about, signified by the ruler of the house that matches the question's topic.
Perfection
How the matter comes to pass: the two significators completing an applying aspect (direct), or a faster planet carrying their light between them (translation), or both applying to a common slower planet (collection). No perfection generally means 'no'.
Applying vs separating
An applying aspect is still forming — the faster planet is moving toward exactness — and can bring a future matter about. A separating aspect is already past and describes what is done. Only applying aspects perfect a horary question.
Essential dignity
A planet's strength by zodiac position, scored by Lilly's scheme: domicile +5, exaltation +4, triplicity +3, term +2, face +1, with detriment −5, fall −4, and peregrine (no dignity at all) −5. It shows how capable and well-disposed a significator is.
Reception
When a planet sits in a sign another planet rules or is exalted in, the dignity-lord 'receives' it. Mutual reception (each in the other's dignity) signals the parties are willing and can rescue a difficult aspect — 'reception is intention'.
Void of course & via combusta
A void-of-course Moon makes no further applying aspect before leaving its sign ('nothing comes of it'); the via combusta (15° Libra–15° Scorpio) marks an unstable, clouded matter. Both are cautions, not automatic refusals to judge.
Considerations before judgement
Classical warning signs — an Ascendant too early (<3°) or too late (>27°), Saturn in the 1st or 7th, an afflicted 7th ruler — that the question may be premature, decided, or that the astrologer should take extra care. Treated here as flags, never hard gates.

API

The askTIAN Horary API casts a Lilly-faithful question chart — traditional seven-planet rulerships, the five essential dignities, Regiomontanus houses, moiety orbs and applying/separating aspects — and judges perfection by direct aspect, translation or collection of light. It returns the querent and quesited significators, the Moon's condition (void-of-course, via combusta, next aspect), mutual reception, a yes/qualified/no verdict, a hedged timing estimate, the classical considerations as flags, and a transparent 0–100 favorability score with a fixed-section LLM judgement. The astronomy is exact; the judgement is a symbolic tradition, not a validated predictor. Set interpretation:false for structured data only.

Endpoint: POST /trpc/horary.judge — 7 TIAN Points. See the API documentation and Playground.