POST/v1/western/synastry

Western Synastry

Aspect grid between two natal charts using the tropical zodiac. Returns all inter-chart aspects using standard modern Western orbs. Useful for relationship compatibility analysis.

Request parameters

person1required

object

person1.locationoptional

string | null

City name to resolve to lat/lon/tz automatically. Example: 'Mumbai' or 'New Delhi, India'. If provided, latitude, longitude and timezone are not required.

person1.nameoptional

string

Person name associated with the birth record

person1.daterequired

string

Birth date in YYYY-MM-DD format

person1.timeoptional

string | null

Birth time in HH:MM 24-hour format. If omitted, sunrise chart is used as fallback.

person1.latitudeoptional

number | null

Latitude. Required if location not provided.

person1.longitudeoptional

number | null

Longitude. Required if location not provided.

person1.timezoneoptional

string | null

IANA timezone. Required if location not provided.

person1.ayanamsaoptional

string

Sidereal ayanamsa mode used in calculations

person2required

object

person2.locationoptional

string | null

City name to resolve to lat/lon/tz automatically. Example: 'Mumbai' or 'New Delhi, India'. If provided, latitude, longitude and timezone are not required.

person2.nameoptional

string

Person name associated with the birth record

person2.daterequired

string

Birth date in YYYY-MM-DD format

person2.timeoptional

string | null

Birth time in HH:MM 24-hour format. If omitted, sunrise chart is used as fallback.

person2.latitudeoptional

number | null

Latitude. Required if location not provided.

person2.longitudeoptional

number | null

Longitude. Required if location not provided.

person2.timezoneoptional

string | null

IANA timezone. Required if location not provided.

person2.ayanamsaoptional

string

Sidereal ayanamsa mode used in calculations

Response fields

success

boolean

True if the request succeeded

message

string

Human-readable status message

data

object

data.aspects

array[object]

data.aspects[].person1_planet

string

data.aspects[].person2_planet

string

data.aspects[].type

string

data.aspects[].exact_angle

number

data.aspects[].orb

number

data.total_aspects

integer

Errors

authentication_failed

Missing or invalid API key.

ephemeris_unavailable

Upstream ephemeris service error.

insufficient_tier

API key tier does not include this endpoint.

internal_error

Unexpected server error.

ip_rate_limit_exceeded

Too many requests in a short window.

payload_too_large

Request body exceeds the size limit.

resource_not_found

Referenced resource was not found.

validation_error

Request body failed schema validation.

Related endpoints

• Western Compatibility Score
• Western Composite Chart
• Western Zodiac Sign Compatibility

Request

POST·application/json

curl

curl -X POST "https://api.asterwise.com/v1/western/synastry" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"person1":{"name":"Arjun Mehta","date":"1985-11-12","time":"06:45","latitude":19.076,"longitude":72.8777,"timezone":"Asia/Kolkata"},"person2":{"name":"Sofia Shah","date":"1988-03-24","time":"14:30","latitude":28.6139,"longitude":77.209,"timezone":"Asia/Kolkata"}}'

Python

import asterwise
from asterwise.api.western_astrology_api import WesternAstrologyApi
from asterwise.models.two_person_request import TwoPersonRequest

configuration = asterwise.Configuration(
    host="https://api.asterwise.com",
    access_token="YOUR_API_KEY",
)

request = TwoPersonRequest(
    person1={'name': 'Arjun Mehta', 'date': '1985-11-12', 'time': '06:45', 'latitude': 19.076, 'longitude': 72.8777, 'timezone': 'Asia/Kolkata'},
    person2={'name': 'Sofia Shah', 'date': '1988-03-24', 'time': '14:30', 'latitude': 28.6139, 'longitude': 77.209, 'timezone': 'Asia/Kolkata'},
)

with asterwise.ApiClient(configuration) as client:
    api = WesternAstrologyApi(client)
    result = api.western_synastry(two_person_request=request)
    print(result)

TypeScript

import { createClient, createConfig, westernSynastry } from 'asterwise';

const client = createClient(createConfig({
  baseUrl: 'https://api.asterwise.com',
  headers: { Authorization: 'Bearer YOUR_API_KEY' },
}));

const result = await westernSynastry({
  client,
  body: {
      "person1": {
        "name": "Arjun Mehta",
        "date": "1985-11-12",
        "time": "06:45",
        "latitude": 19.076,
        "longitude": 72.8777,
        "timezone": "Asia/Kolkata"
      },
      "person2": {
        "name": "Sofia Shah",
        "date": "1988-03-24",
        "time": "14:30",
        "latitude": 28.6139,
        "longitude": 77.209,
        "timezone": "Asia/Kolkata"
      }
  },
});

console.log(result.data);

Response

200 OK·application/jsonsigned

{
  "success": true,
  "message": "success",
  "data": {
    "aspects": [
      {
        "person1_planet": "Sun",
        "person2_planet": "Sun",
        "type": "sesquiquadrate",
        "exact_angle": 134.3467,
        "orb": 0.6533
      },
      {
        "person1_planet": "Sun",
        "person2_planet": "Venus",
        "type": "opposition",
        "exact_angle": 179.9187,
        "orb": 0.0813
      },
      "... and 23 more items"
    ],
    "total_aspects": 25
  }
}