Western Solar Return
asterwise_get_western_solar_return
Solar return chart for a given year. Finds the exact moment the Sun returns to its natal tropical longitude and builds a complete Western natal chart for that moment at the birth location. Provide the year as an integer (e.g. 2026).
Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
birth | object | yes | Birth data for Western astrology tools (tropical zodiac). Fields: date, time, lat, lon, person_name, timezone, house_system |
year | integer | yes | Four-digit calendar year, e.g. 2026. |
response_format | enum: markdown, json | no | Output format: 'markdown' (default) for a readable report, or 'json' for the raw structured payload. |
What it covers
Annual solar return — the chart cast for the precise instant the transiting Sun reaches the natal Sun's longitude, relocated to birth place (not relocated charts). The embedded data.chart is a full tropical chart at that instant.
Workflow
BEFORE: asterwise_get_western_natal — understand natal chart before reading return.
AFTER: None.
Input
birth — WesternBirthData. house_system ignored (chart uses return computation defaults).
year (int) — calendar year of the return (e.g. 2026), not age.
Output contract
data.planet — 'Sun'
data.natal_longitude (float — natal Sun tropical longitude)
data.return_utc (string — ISO 8601 UTC moment of return)
data.return_jd (float — Julian Day of return)
data.chart — full Western natal chart at return moment
Response format
response_format=json serialises the complete response as indented JSON.
response_format=markdown renders the same data as a human-readable report.
Both modes return identical underlying data.
Compute class
MEDIUM_COMPUTE (~800ms, iterative Sun longitude search)
Errors
INVALID_PARAMS (local): WesternBirthData validation failures.
INTERNAL_ERROR: Any upstream API failure or timeout → MCP INTERNAL_ERROR
Edge cases:
year param is the calendar year of the return (e.g., 2026), not the age. Feeding age instead of year silently produces the wrong return chart.
Do not confuse with
asterwise_get_western_lunar_return — Moon return, ~monthly.
asterwise_get_varshaphal — Vedic Tajika solar return — different system.
Connect
Remote MCP endpoint: https://mcp.asterwise.com/mcp. Authenticate with Authorization: Bearer <API key> or OAuth. See the MCP setup guide.