Moon Phase and Lunar Calendar

Get a clean, day by day lunar calendar for any date range and any place on Earth. This actor returns the moon phase, the percent illuminated, the moon's age, its distance from Earth, the exact times of new, first quarter, full, and last quarter moons, and optional moonrise and moonset for a location you choose.

Everything is computed offline from a built in ephemeris. There is no API to call, no key to manage, and no website to scrape, so results are fast and the tool keeps working without maintenance.

What you get

One row per day with these fields:

• date and weekday
• phase emoji and phase name, from new moon through waning crescent
• illumination as a percentage
• moon age in days since the last new moon
• distance from Earth in kilometres
• principal phase and its exact time, on the days a new, first quarter, full, or last quarter moon occurs
• moonrise and moonset for your latitude and longitude, when you ask for them

Days with no moonrise or no moonset, which happen about once a month, are left blank rather than guessed.

Who uses it

Gardeners and planting calendars that follow the lunar cycle. Anglers timing trips around the moon. Photographers planning full moon and dark sky shoots. Event and wedding planners who want to know how bright the night will be. Anyone building a calendar app or almanac that needs reliable phase data.

Input

All fields have sensible defaults, so a run with no changes returns a 30 day calendar starting today for London in UTC.

Field	Description	Default
Start date	First day, in YYYY-MM-DD. Empty means today.	today
Number of days	How many days to return, one row each.	30
Include moonrise and moonset	Add rise and set times for the location below.	on
Latitude	Observer latitude in decimal degrees.	51.5074
Longitude	Observer longitude in decimal degrees.	-0.1278
Time zone	IANA name such as UTC, Europe/London, or America/New_York. All dates and times use it.	UTC

Example output

{
  "date": "2026-07-29",
  "weekday": "Wednesday",
  "phaseName": "Full Moon",
  "phaseEmoji": "🌕",
  "illuminationPercent": 100.0,
  "moonAgeDays": 15.09,
  "distanceKm": 399901,
  "principalPhase": "Full Moon",
  "principalPhaseTime": "2026-07-29 14:35",
  "moonrise": "2026-07-29 20:41",
  "moonset": "2026-07-29 04:52"
}

Accuracy

Phase, illumination, distance, and the principal phase times come from the ephem library, the Python binding to the long standing XEphem astronomy engine. Phase times are accurate to within about a minute. Moonrise and moonset use standard atmospheric refraction and are accurate to a minute or two, which is the usual precision for an almanac.

Notes on time zones

The date of a full or new moon can differ by one calendar day depending on the zone you pick, because the exact moment is a single instant worldwide. Set the time zone to your own to see the calendar the way your sky shows it.