lunar

Get Void of Course Moon status

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:

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

Query parameters

datetimestring 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_modestring

Zodiac mode: 'tropical' or 'sidereal'

formatstring

Response format: json | llm.

Headers

authorizationstring nullable
X-API-Keystring nullable
X-OpenEphemeris-API-Keystring nullable
apikeystring nullable

Response

Successful Response

current_signstring required

Moon's current zodiac sign

is_voidboolean required

True if Moon is currently Void of Course

last_aspectobject

Last major aspect before ingress (COQTS: conjunction, opposition, square, trine, sextile)

metadataobject required

Calculation metadata (calculation_time_ms, cache_hit)

next_signstring required

Next zodiac sign Moon will enter

successboolean

Calculation success status

void_endstring date-time

VoC period end (next sign ingress time)

void_startstring date-time

VoC period start (last aspect time or previous ingress if no aspects)

Example response

{
  "current_sign": "Gemini",
  "is_void": true,
  "last_aspect": {
    "aspect_type": "sextile",
    "planet": "Venus",
    "time": "2025-12-11T14:32:00+00:00"
  },
  "metadata": {
    "cache_hit": false,
    "calculation_time_ms": 25.3
  },
  "next_sign": "Cancer",
  "success": true,
  "void_end": "2025-12-11T18:45:00+00:00",
  "void_start": "2025-12-11T14:32:00+00:00"
}

Changes

No recorded changes to this operation across all 1 revision of this API.