moontool

Get information about the moon, in javascript.

The source of algorithms comes from Moontool for Windows, which the source of the application has been copied to this repo in /original for safekeeping/archival.

Methods available

Method	Returns
getMoonInfo(date)	Returns information about the moon on a given date
getEaster(year)	Returns the date of Easter for a given year

Examples

getMoonInfo(new Date());

// Result
{
    angularDiameterInDeg: 0.5227003811621781,
    distanceInKm: 381017.8168555941,
    distanceToSun: 149979823.99030265​,
    moonAgeInDays: 8.807861270471863​, // min 0, max 29.53
    moonIllumination: 0.6493074320692747​, // 0 new moon, 1 full moon
    moonPhase: 0.298262298998364​, // percentage of the current phase of the moon (new moon (0) > full moon > new moon (1))
    sunAngularDiameter: 0.5317725210369415
}

getEaster(2020); // -> Sun Apr 12 2020

Usage

This package works both in CJS / ESM formats.

const moontool = require("@mrspade/moontool");
moontool.getEaster(2020);

// or

import { getMoonInfo } from "@mrspade/moontool";
getMoonInfo(new Date());

Building locally

npm i

Package

Ensure you have ran npm i

Run npm run build