ephemeris

Calculate lunar phase for datetime

Calculate the current lunar phase based on Sun-Moon elongation. Returns phase name/angle, illumination percentage, and lunation metadata (New Moon/Full Moon dates, day of lunation, void-of-course status). 🤖 AI-optimized output available — add format=llm to reduce payload ~50%.

post/ephemeris/lunar-phase

Request

  • Base URL: https://api.openephemeris.com
  • URL: https://api.openephemeris.com/ephemeris/lunar-phase
  • 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

output_modestring nullable

Deprecated: use preset+format. Accepts full|simple|llm.

formatstring

Headers

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

Request body

Example request

{
  "date_time": {
    "iso": "2025-12-11T12:00:00Z"
  }
}

Response

Successful Response

metadataobject required

Calculation metadata and settings

successboolean

Calculation success status

Changes

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