GET/v1/western/moon/phase

Western Moon Phase

Calculate the lunar phase for any date using the tropical zodiac. Returns phase name (New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, Waning Crescent), phase angle, illumination percentage, moon age in days, and next major phase estimate. Defaults to today if no date given.

Request parameters

dateoptional

string | null

Date in YYYY-MM-DD format. Defaults to today.

Response fields

success

boolean

True if the request succeeded

message

string

Human-readable status message

data

object

data.date

string

Date in YYYY-MM-DD format

data.phase_name

string

Current phase name

data.phase_angle

number

Phase angle in degrees (0-360). 0=New Moon, 180=Full Moon

data.illumination_pct

number

Percentage of Moon disk illuminated (0-100)

data.moon_age_days

number

Days elapsed since last New Moon (0 to 29.53)

data.moon_longitude

number

Tropical ecliptic longitude of Moon (0-360)

data.sun_longitude

number

Tropical ecliptic longitude of Sun (0-360)

data.is_waxing

boolean

True if Moon is waxing (phase_angle < 180)

data.next_phase_name

string

Name of the next major phase

data.next_phase_date

string | null

Estimated date of next major phase (YYYY-MM-DD)

Errors

authentication_failed

Missing or invalid API key.

ephemeris_unavailable

Upstream ephemeris service error.

insufficient_tier

API key tier does not include this endpoint.

internal_error

Unexpected server error.

ip_rate_limit_exceeded

Too many requests in a short window.

payload_too_large

Request body exceeds the size limit.

resource_not_found

Referenced resource was not found.

validation_error

Request body failed schema validation.

Related endpoints

• Biorhythm Cycles
• Western Moon Phase Calendar

Request

GET·application/json

curl

curl -X GET "https://api.asterwise.com/v1/western/moon/phase?date=2026-01-01" \
  -H "Authorization: Bearer YOUR_API_KEY"

Python

import asterwise
from asterwise.api.western_astrology_api import WesternAstrologyApi

configuration = asterwise.Configuration(
    host="https://api.asterwise.com",
    access_token="YOUR_API_KEY",
)

with asterwise.ApiClient(configuration) as client:
    api = WesternAstrologyApi(client)
    result = api.western_moon_phase(date="2026-01-01")
    print(result)

TypeScript

import { createClient, createConfig, westernMoonPhase } from 'asterwise';

const client = createClient(createConfig({
  baseUrl: 'https://api.asterwise.com',
  headers: { Authorization: 'Bearer YOUR_API_KEY' },
}));

const result = await westernMoonPhase({
  client,
  query: {
      "date": "2026-01-01"
  },
});

console.log(result.data);

Response

200 OK·application/jsonsigned

{
  "success": true,
  "message": "success",
  "data": {
    "date": "2026-01-01",
    "phase_name": "Waxing Gibbous",
    "phase_angle": 156.6555,
    "illumination_pct": 95.91,
    "moon_age_days": 12.85,
    "moon_longitude": 77.98827,
    "sun_longitude": 281.332736,
    "is_waxing": true,
    "next_phase_name": "Full Moon",
    "next_phase_date": "2026-01-03"
  }
}