JavaScript examples for Node.js

The source file astronomy.js works as a Node.js module. Download the file into your project directory. Then in your own source file, do this:

const Astronomy = require('astronomy.js');

There are no external dependencies! Astronomy Engine is completely self-contained, and it always will be.

(By the way, you can use the same file astronomy.js for astronomy calculations inside the browser.)

This example shows how to determine the Moon's current phase, and how to predict when the next few quarter phases will occur.

Calculates equatorial and horizontal coordinates of the Sun, Moon, and planets.

API Reference

Complete documentation for all the functions and types available in the JavaScript version of Astronomy Engine.