POST · WESTERN

Transit Aspects

Endpoint POST https://starsapi.com/api/v3/western/predictions/transit-natal-aspects

Computes current (or specified date) planetary positions and finds all major aspects between transiting planets and natal planets. Returns each aspect with orb deviation, applying/separating status, nature label, retrograde flag, and a prewritten interpretation with keyword pills. Covers all 5 major aspects (conjunction, sextile, square, trine, opposition) between 10 transiting and 10 natal planets — 470 unique interpretations written specifically for the transit context.

This is the #1 engagement feature for subscription astrology apps — “Transiting Saturn is squaring your natal Neptune” is the language that makes users open the app every day.

Transit vs Natal — transit interpretations describe temporary influences with timing awareness, not permanent personality traits. “Saturn square your Neptune” as a transit means a period of reality-testing your dreams; as a natal aspect it means a lifelong tension between structure and imagination. The content is entirely different.

Transit orbs

AspectAngleGeneral orbLuminary orbNature
Conjunction10°Fusion
Sextile60°Smooth
Square90°Friction
Trine120°Lucky
Opposition180°Tense

Luminary orbs apply when either the transiting or the natal planet is the Sun or Moon.

Authentication

MethodExample
Header (recommended)X-Api-Key: am_live_xxxxxxxxxxxx
BearerAuthorization: Bearer am_live_xxxxxxxxxxxx
Query?api_key=am_live_xxxxxxxxxxxx

Request body

FieldTypeRequiredDescription
Natal birth data
yearintegerYesBirth year (1800–2400).
monthintegerYesBirth month, 1–12.
dayintegerYesBirth day.
hourintegerYesBirth hour, 0–23.
minuteintegerYesBirth minute, 0–59.
secondintegerNoDefault 0.
latitudenumberYesBirth latitude, decimal degrees.
longitudenumberYesBirth longitude, decimal degrees.
timezonestringYesBirth IANA timezone.
Transit date (optional — defaults to now)
transit_yearintegerNoTransit year (1800–2400).
transit_monthintegerNoTransit month.
transit_dayintegerNoTransit day.
transit_hourintegerNoTransit hour. Default 12.
transit_minuteintegerNoTransit minute. Default 0.
transit_timezonestringNoTransit timezone. Defaults to natal timezone.
Options
languagestringNoLanguage code. Default en.
house_systemstringNoDefault placidus.

Response shape

FieldTypeDescription
natal_datestringBirth date (YYYY-MM-DD).
transit_datestringTransit date (YYYY-MM-DD).
aspect_countintegerNumber of in-orb transit aspects found.
transit_aspects[]arraySorted by orb (tightest first). Each entry:
.transit_planetstringTransiting planet name.
.transit_signstringSign the transiting planet currently occupies.
.natal_planetstringNatal planet being aspected.
.natal_signstringSign the natal planet occupies.
.aspectstringOne of conjunction, sextile, square, trine, opposition.
.naturestringUI label: Fusion, Smooth, Friction, Lucky, Tense.
.orb_deviationnumberDeviation from exact aspect, decimal degrees.
.applyingbooleantrue if aspect is tightening, false if separating.
.transit_retrogradebooleanWhether the transiting planet is retrograde.
.predictionobjecttitle, text, keywords array.

Usage notes

For daily horoscope apps, call this endpoint once per day per user with transit_year/month/day set to today. The tightest-orb aspects (first in the array) are the most relevant influences for that day. Outer planet transits (Saturn, Uranus, Neptune, Pluto) are the most commercially valuable because they describe multi-week or multi-month themes that drive subscription engagement.

Errors

HTTPCodeCause
400MISSING_FIELDRequired field absent.
400INVALID_DATEBad natal or transit date.
400INVALID_TIMEZONENon-IANA timezone.
400INVALID_COORDINATELat/lon out of range.
405METHOD_NOT_ALLOWEDNon-POST request.

See also