---
title: "Void-of-course Moon"
method: POST
path: "/v1/western/moon/void-of-course"
tags: ["Western Astrology"]
---

# Void-of-course Moon

`POST /v1/western/moon/void-of-course`

## Request

- Base URL: `https://api.asterwise.com`
- URL: `https://api.asterwise.com/v1/western/moon/void-of-course`
- Auth: HTTP bearer

Void-of-course Moon periods in a date range (UTC). Rule used: the traditional one — the Moon is void from its last exact Ptolemaic aspect (conjunction, sextile, square, trine, opposition) to the Sun, Mercury, Venus, Mars, Jupiter or Saturn until it enters the next sign (William Lilly, Christian Astrology, 1647, p. 112). Outer planets are not counted. Each period gives start and end in UTC, the last aspect, the sign the Moon is in and the sign it enters next. Range limit 92 days.

## Request body

- VoidOfCourseRequest
  - `from_date` string, required: First day of the range (YYYY-MM-DD, UTC).
  - `to_date` string, required: Last day of the range (YYYY-MM-DD, UTC, inclusive). At most 92 days after from_date.

## Response `200`

Successful Response

- ApiResponseVoidOfCourseResponse
  - `success` boolean: True if the request succeeded
  - `message` string: Human-readable status message
  - `data` VoidOfCourseResponse, required
    - `from_date` string, required
    - `to_date` string, required
    - `definition` string, required: Plain-English statement of the rule used.
    - `periods` VoidOfCoursePeriod[], required: Void-of-course periods that overlap the range, in time order.
      - `start_utc` string, required: When the void-of-course period starts (last exact aspect), UTC.
      - `end_utc` string, required: When it ends: the Moon enters the next sign, UTC.
      - `duration_hours` number, required: Length of the void period in hours.
      - `moon_sign` string, required: Sign the Moon is in while void.
      - `moon_sign_index` integer, required
      - `next_sign` string, required: Sign the Moon enters at end_utc.
      - `next_sign_index` integer, required
      - `last_aspect` VoidOfCourseLastAspect
        - `planet` string, required: Planet of the Moon's last exact aspect in the sign.
        - `aspect` string, required: Aspect type: conjunction, sextile, square, trine or opposition.
        - `exact_at` string, required: UTC moment that aspect was exact (ISO 8601 with Z).
      - `whole_sign_void` boolean, required: True when the Moon made no exact aspect at all while in the sign, so it was void for the whole passage.

## Other responses

- `401`: Authentication failed
- `403`: Authorization failed
- `404`: Resource not found
- `413`: Payload too large
- `422`: Validation error
- `429`: Rate limit exceeded
- `500`: Internal error
- `502`: Upstream provider error
- `503`: Service unavailable

---

[API](https://skmtc.dev/asterwise/apis/asterwise-api.md) · [All operations](https://skmtc.dev/asterwise/apis/asterwise-api/llms.txt) · [OpenAPI document](https://skmtc.dev/asterwise/apis/asterwise-api/revisions/e77850f7c569?raw)