---
title: "Get Void of Course Moon status"
method: GET
path: "/ephemeris/moon/void-of-course"
tags: ["lunar"]
---

# Get Void of Course Moon status

`GET /ephemeris/moon/void-of-course`

## Request

- Base URL: `https://api.openephemeris.com`
- URL: `https://api.openephemeris.com/ephemeris/moon/void-of-course`
- Auth: one of:
  - HTTP bearer
  - API key in header `X-OpenEphemeris-API-Key`
  - API key in header `X-API-Key`
  - API key in header `X-Service-Key`

Returns Void of Course Moon status for a specific datetime using **Method 3 definition**.

**Void of Course (VoC) Definition:**  
Moon is VoC when it makes no major aspects (conjunction, opposition, square, trine, sextile)
to traditional planets (Sun through Pluto) before changing zodiac signs.

**Method 3 Logic:**
- VoC period **cannot start before** Moon's last sign ingress
- Searches backwards from next ingress for last major aspect (COQTS)
- If no aspects found, VoC starts at previous ingress (calendar-accurate)
- Uses fixed traditional orbs (no custom orbs in v1)

**Performance:** 20-50ms (aspect search + ingress calculation)

**Use Cases:**
- Electional astrology: "Is now a good time to sign contracts?"
- Daily VoC calendars for timing decisions
- Timing-sensitive decision support tools

**Example:**
```bash
GET /ephemeris/moon/void-of-course?datetime=2025-12-11T12:00:00Z&zodiac_mode=tropical
```

## Query parameters

- `datetime` string, required: ISO-8601 datetime, e.g. '2025-12-11T12:00:00Z'. A clock time must carry its own zone ('Z' or ±HH:MM); a zone-less clock time is rejected with 400 ambiguous_datetime. A date-only value resolves to 12:00 UTC.
- `zodiac_mode` string: Zodiac mode: 'tropical' or 'sidereal'
- `format` string: Response format: json | llm.

## Headers

- `authorization` string, nullable
- `X-API-Key` string, nullable
- `X-OpenEphemeris-API-Key` string, nullable
- `apikey` string, nullable

## Response `200`

Successful Response

- VoidOfCourseResponse: Calculated Void of Course window for the Moon, detailing the last major planetary aspect before its ingress into the next zodiac sign.
  - `current_sign` string, required: Moon's current zodiac sign
  - `is_void` boolean, required: True if Moon is currently Void of Course
  - `last_aspect` object: Last major aspect before ingress (COQTS: conjunction, opposition, square, trine, sextile)
  - `metadata` object, required: Calculation metadata (calculation_time_ms, cache_hit)
  - `next_sign` string, required: Next zodiac sign Moon will enter
  - `success` boolean: Calculation success status
  - `void_end` string, date-time: VoC period end (next sign ingress time)
  - `void_start` string, date-time: VoC period start (last aspect time or previous ingress if no aspects)

## Other responses

- `400`: Bad Request
- `422`: Unprocessable Entity - Invalid input format
- `500`: Internal Server Error

---

[API](https://skmtc.dev/openephemeris/apis/open-ephemeris-api.md) · [All operations](https://skmtc.dev/openephemeris/apis/open-ephemeris-api/llms.txt) · [OpenAPI document](https://skmtc.dev/openephemeris/apis/open-ephemeris-api/revisions/d195a769cb89?raw)