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

Aspect	Angle	General orb	Luminary orb	Nature
Conjunction	0°	8°	10°	Fusion
Sextile	60°	4°	5°	Smooth
Square	90°	6°	8°	Friction
Trine	120°	6°	8°	Lucky
Opposition	180°	6°	8°	Tense

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

Authentication

Method	Example
Header (recommended)	`X-Api-Key: sa_live_xxxxxxxxxxxx`
Bearer	`Authorization: Bearer sa_live_xxxxxxxxxxxx`
Query	`?api_key=sa_live_xxxxxxxxxxxx`

Request body

Field	Type	Required	Description
Natal birth data
`year`	integer	Yes	Birth year (1800–2400).
`month`	integer	Yes	Birth month, 1–12.
`day`	integer	Yes	Birth day.
`hour`	integer	Yes	Birth hour, 0–23.
`minute`	integer	Yes	Birth minute, 0–59.
`second`	integer	No	Default 0.
`latitude`	number	Yes	Birth latitude, decimal degrees.
`longitude`	number	Yes	Birth longitude, decimal degrees.
`timezone`	string	Yes	Birth IANA timezone.
Transit date (optional — defaults to now)
`transit_year`	integer	No	Transit year (1800–2400).
`transit_month`	integer	No	Transit month.
`transit_day`	integer	No	Transit day.
`transit_hour`	integer	No	Transit hour. Default 12.
`transit_minute`	integer	No	Transit minute. Default 0.
`transit_timezone`	string	No	Transit timezone. Defaults to natal timezone.
Options
`language`	string	No	Language code. Default `en`.
`house_system`	string	No	Default `placidus`.
`include_timing`	boolean	No	Default `false`. When `true`, every aspect gains a `timing` object with entry → exact → exit datetimes. Response is unchanged when omitted.
`timing_scope`	string	No	`active` (default) or `nearest`. See Aspect timing.
`node_type`	string	No	`mean` (default) or `true` — node used by the timing engine.

Aspect timing

Pass include_timing: true to attach precise entry → exact → exit timing to each aspect, computed by the same engine as transit/natal-transit-aspects.

`timing_scope`	What it returns	Speed
`active`	Timing only for aspects whose orb window is active on the transit date (typically 10–20). Others get `timing: null`.	Fast (<0.5s) — use for the first screen.
`nearest`	The nearest exact (past or future, ±1 year) for every aspect. `future: true` means the perfection is still ahead.	Heavier (~2–3s) — load on demand (e.g. behind a “show timing” tap).

timing is null when no exact falls within the scope, and for mirrored node pairs (transiting North Node ↔ natal South Node) — those duplicate the corresponding same-node aspect, which does carry timing. Local times are in the transit timezone; UTC fields are always provided.

Response shape

Field	Type	Description
`natal_date`	string	Birth date (YYYY-MM-DD).
`transit_date`	string	Transit date (YYYY-MM-DD).
`aspect_count`	integer	Number of in-orb transit aspects found.
`transit_aspects[]`	array	Sorted by orb (tightest first). Each entry:
`.transit_planet`	string	Transiting planet name.
`.transit_sign`	string	Sign the transiting planet currently occupies.
`.natal_planet`	string	Natal planet being aspected.
`.natal_sign`	string	Sign the natal planet occupies.
`.aspect`	string	One of `conjunction`, `sextile`, `square`, `trine`, `opposition`.
`.nature`	string	UI label: `Fusion`, `Smooth`, `Friction`, `Lucky`, `Tense`.
`.orb_deviation`	number	Deviation from exact aspect, decimal degrees.
`.applying`	boolean	`true` if aspect is tightening, `false` if separating.
`.transit_retrograde`	boolean	Whether the transiting planet is retrograde.
`.prediction`	object	`title`, `text`, `keywords` array.
`.timing`	object\|null	Only when `include_timing` is true. `entry_utc/entry_local`, `exact_utc/exact_local`, `exit_utc/exit_local`, `duration_days`, `phase` (applying/separating), `is_perfected`, `future`.
`timing_scope`	string	Echoed when `include_timing` is true.

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

HTTP	Code	Cause
400	`MISSING_FIELD`	Required field absent.
400	`INVALID_DATE`	Bad natal or transit date.
400	`INVALID_TIMEZONE`	Non-IANA timezone.
400	`INVALID_COORDINATE`	Lat/lon out of range.
400	`INVALID_PARAM`	`timing_scope` not `active`/`nearest`.
405	`METHOD_NOT_ALLOWED`	Non-POST request.

# Replace YOUR_API_KEY with the key from your dashboard
curl -X POST "https://starsapi.com/api/v3/western/predictions/transit-natal-aspects" \
  -H "X-Api-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
        "name": "Priya",
        "gender": "female",
        "year": 1990,
        "month": 5,
        "day": 20,
        "hour": 14,
        "minute": 30,
        "second": 0,
        "latitude": 28.6139,
        "longitude": 77.209,
        "timezone": "Asia/Kolkata",
        "language": "en",
        "transit_year": 2026,
        "transit_month": 6,
        "transit_day": 13
    }'

const response = await fetch(
  'https://starsapi.com/api/v3/western/predictions/transit-natal-aspects',
  {
    method: 'POST',
    headers: {
      'X-Api-Key': 'YOUR_API_KEY',
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      name: 'Priya',
      gender: 'female',
      year: 1990,
      month: 5,
      day: 20,
      hour: 14,
      minute: 30,
      second: 0,
      latitude: 28.6139,
      longitude: 77.209,
      timezone: 'Asia/Kolkata',
      language: 'en',
      transit_year: 2026,
      transit_month: 6,
      transit_day: 13
    })
  }
);
const result = await response.json();

if (result.success) {
  console.log(result.data);
}

import requests
import os

response = requests.post(
    'https://starsapi.com/api/v3/western/predictions/transit-natal-aspects',
    headers={'X-Api-Key': os.environ['STARSAPI_KEY']},
    json={
        'name': 'Priya',
        'gender': 'female',
        'year': 1990,
        'month': 5,
        'day': 20,
        'hour': 14,
        'minute': 30,
        'second': 0,
        'latitude': 28.6139,
        'longitude': 77.209,
        'timezone': 'Asia/Kolkata',
        'language': 'en',
        'transit_year': 2026,
        'transit_month': 6,
        'transit_day': 13
    }
)
result = response.json()

if result['success']:
    print(result['data'])

<?php
$payload = [
    'name' => 'Priya',
    'gender' => 'female',
    'year' => 1990,
    'month' => 5,
    'day' => 20,
    'hour' => 14,
    'minute' => 30,
    'second' => 0,
    'latitude' => 28.6139,
    'longitude' => 77.209,
    'timezone' => 'Asia/Kolkata',
    'language' => 'en',
    'transit_year' => 2026,
    'transit_month' => 6,
    'transit_day' => 13,
];

$ch = curl_init('https://starsapi.com/api/v3/western/predictions/transit-natal-aspects');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($payload));
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'X-Api-Key: ' . getenv('STARSAPI_KEY'),
    'Content-Type: application/json'
]);

$response = curl_exec($ch);
$data = json_decode($response, true);

if ($data['success']) {
    print_r($data['data']);
}

import 'package:http/http.dart' as http;
import 'dart:convert';

Future<Map<String, dynamic>> getAscendant() async {
  final response = await http.post(
    Uri.parse('https://starsapi.com/api/v3/western/predictions/transit-natal-aspects'),
    headers: {
      'X-Api-Key': 'YOUR_API_KEY',
      'Content-Type': 'application/json',
    },
    body: jsonEncode({
      'name': 'Priya',
      'gender': 'female',
      'year': 1990,
      'month': 5,
      'day': 20,
      'hour': 14,
      'minute': 30,
      'second': 0,
      'latitude': 28.6139,
      'longitude': 77.209,
      'timezone': 'Asia/Kolkata',
      'language': 'en',
      'transit_year': 2026,
      'transit_month': 6,
      'transit_day': 13,
    }),
  );
  return jsonDecode(response.body);
}

import Foundation

func getAscendant() async throws -> [String: Any] {
    var request = URLRequest(url: URL(string:
        "https://starsapi.com/api/v3/western/predictions/transit-natal-aspects"
    )!)
    request.httpMethod = "POST"
    request.setValue("YOUR_API_KEY", forHTTPHeaderField: "X-Api-Key")
    request.setValue("application/json", forHTTPHeaderField: "Content-Type")
    request.httpBody = """
        {
            "name": "Priya",
            "gender": "female",
            "year": 1990,
            "month": 5,
            "day": 20,
            "hour": 14,
            "minute": 30,
            "second": 0,
            "latitude": 28.6139,
            "longitude": 77.209,
            "timezone": "Asia/Kolkata",
            "language": "en",
            "transit_year": 2026,
            "transit_month": 6,
            "transit_day": 13
        }
        """.data(using: .utf8)

    let (data, _) = try await URLSession.shared.data(for: request)
    return try JSONSerialization.jsonObject(with: data) as! [String: Any]
}

import okhttp3.*
import org.json.JSONObject

val client = OkHttpClient()
val JSON = "application/json; charset=utf-8".toMediaType()

fun getAscendant(callback: (JSONObject) -> Unit) {
    val payload = """
    {
        "name": "Priya",
        "gender": "female",
        "year": 1990,
        "month": 5,
        "day": 20,
        "hour": 14,
        "minute": 30,
        "second": 0,
        "latitude": 28.6139,
        "longitude": 77.209,
        "timezone": "Asia/Kolkata",
        "language": "en",
        "transit_year": 2026,
        "transit_month": 6,
        "transit_day": 13
    }
    """.trimIndent()

    val request = Request.Builder()
        .url("https://starsapi.com/api/v3/western/predictions/transit-natal-aspects")
        .addHeader("X-Api-Key", "YOUR_API_KEY")
        .post(payload.toRequestBody(JSON))
        .build()

    client.newCall(request).enqueue(object : Callback {
        override fun onResponse(call: Call, response: Response) {
            callback(JSONObject(response.body!!.string()))
        }
        override fun onFailure(call: Call, e: java.io.IOException) {
            e.printStackTrace()
        }
    })
}

package main

import (
    "bytes"
    "encoding/json"
    "fmt"
    "net/http"
    "os"
)

func main() {
    payload, _ := json.Marshal(map[string]interface{}{
        "name": "Priya",
        "gender": "female",
        "year": 1990,
        "month": 5,
        "day": 20,
        "hour": 14,
        "minute": 30,
        "second": 0,
        "latitude": 28.6139,
        "longitude": 77.209,
        "timezone": "Asia/Kolkata",
        "language": "en",
        "transit_year": 2026,
        "transit_month": 6,
        "transit_day": 13,
    })

    req, _ := http.NewRequest("POST",
        "https://starsapi.com/api/v3/western/predictions/transit-natal-aspects",
        bytes.NewBuffer(payload))
    req.Header.Set("X-Api-Key", os.Getenv("STARSAPI_KEY"))
    req.Header.Set("Content-Type", "application/json")

    resp, _ := http.DefaultClient.Do(req)
    defer resp.Body.Close()

    var result map[string]interface{}
    json.NewDecoder(resp.Body).Decode(&result)
    fmt.Println(result["data"])
}

require 'net/http'
require 'json'

uri = URI('https://starsapi.com/api/v3/western/predictions/transit-natal-aspects')
payload = {
  'name' => 'Priya',
  'gender' => 'female',
  'year' => 1990,
  'month' => 5,
  'day' => 20,
  'hour' => 14,
  'minute' => 30,
  'second' => 0,
  'latitude' => 28.6139,
  'longitude' => 77.209,
  'timezone' => 'Asia/Kolkata',
  'language' => 'en',
  'transit_year' => 2026,
  'transit_month' => 6,
  'transit_day' => 13
}

req = Net::HTTP::Post.new(uri)
req['X-Api-Key'] = ENV['STARSAPI_KEY']
req['Content-Type'] = 'application/json'
req.body = payload.to_json

http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true
res = http.request(req)

data = JSON.parse(res.body)
puts data['data'] if data['success']

200 RESPONSE

{
  "status": 200,
  "success": true,
  "data": {
    "language": "en",
    "natal_date": "1990-05-20",
    "transit_date": "2026-06-13",
    "aspect_count": 31,
    "transit_aspects": [
      {
        "transit_planet": "Saturn",
        "transit_sign": "Pisces",
        "natal_planet": "Neptune",
        "natal_sign": "Capricorn",
        "aspect": "square",
        "nature": "Friction",
        "orb_deviation": 1.09,
        "applying": true,
        "transit_retrograde": true,
        "prediction": {
          "title": "Saturn Square Your Neptune",
          "text": "Harsh reality confronts your dreams and illusions…",
          "keywords": ["Illusion shattered", "Creative block", "Harsh clarity"]
        },
        "timing": {
          "entry_utc": "2026-05-28 12:04", "entry_local": "2026-05-28 17:34",
          "exact_utc": "2026-06-19 08:22", "exact_local": "2026-06-19 13:52",
          "exit_utc": "2026-07-02 21:40",  "exit_local": "2026-07-03 03:10",
          "duration_days": 35.4,
          "phase": "applying",
          "is_perfected": true,
          "future": true
        }
      }
    ],
    "timing_scope": "nearest"
  },
  "meta": { "endpoint": "/api/v3/western/predictions/transit-natal-aspects", "version": "3.0" }
}