AstronomyJS

Astronomical calculations in JavaScript.

🚀 See It in Action!

These tiles were generated using the astronomy-svg library.

👉 Check out the live demo here

🪐 Supported Calculations

• Right Ascension / Declination for celestial body
• Hour Angle / Declination for celestial body
• Altitude / Azimuth for celestial body
• Ephemeris for the Sun (astronomical twilight, nautical twilight, civil twilight)
• Ephemeris for celestial body (rise, set)
• 🔭 Includes Pluto!

Quickstart

🌐 Using the Browser-Ready Minified Script

<script type="text/javascript" src="astronomy-js.min.js"></script>
// latitude, longitude
let astronomyJS = AstronomyJS.initialize(56.2, 18.1)
astronomyJS.getAltAzCoordinatesForObject("Sun");

🌟 Installation (npm)

npm install astronomy-js

Using the JavaScript ES Module

import { AstronomyJS } from "astronomy-js";
// latitude, longitude
let astronomyJS = AstronomyJS.initialize(56.2, 18.1)
astronomyJS.getAltAzCoordinatesForObject("Sun");

📄 License

This project is licensed under the MIT License — feel free to use, modify, and share it.
Please make sure to retain the original license and attribution when reusing or modifying the code.
See the LICENSE file for full details.

🌌 About

This library provides astronomical calculations for leisure purposes only. Some important basic aspects are not implemented, such as:

• Atmospheric refraction

• Orbit perturbations

📚 References

US Naval Observatory, Explanatory Supplement to the Astronomical Almanac, 1992