moon-cycle/.github/wiki/api/functions/cycleMonth.md

moon-cycle v2.0.0

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moon-cycle / cycleMonth

Function: cycleMonth()

cycleMonth(date?): string

Defined in: cycleMonth.ts:16

Maps a date to the corresponding NASA moon phase image for the monthly cycle.

The monthly dataset contains 708 hourly images spanning exactly one synodic month (29.53 days). This function computes the fractional position within the current synodic month relative to the 2023-11-13 new moon anchor and maps that fraction to an image index in [1, 708].

Parameters

date?

Date = ...

The date to resolve. Defaults to the current time.

Returns

string

A zero-padded filename string, e.g. "354.webp".