Aleyan

The ASCII Side of the Moon is a visualization tool that generates accurate representations of the Moon’s phases, apparent size, and libration using ASCII art. It calculates and displays the illuminated portion of the Moon, its changing size due to orbital distance variations, and the wobble known as lunar libration, all rendered in 7-bit ASCII. The tool allows users to select specific dates and locations to see the Moon as it would appear from any position on Earth, including whether it is above or below the horizon and its angular orientation, with options to toggle between observer and celestial reference frames.

Users can interact with the tool through a web interface, which includes a slider to change the date and a world map for selecting location and orientation. For command-line access, the tool provides a curl-based API that returns ASCII representations for specified dates, times, and locations. Additionally, the functionality is available as an npm package, which can be run locally using npx, allowing users to generate ASCII Moon visualizations directly in their terminal for any chosen date.

The lunar calculations are powered by the astronomy-engine package, and the ASCII images are derived from Blender-rendered images of the Moon, processed with Chafa. The npm package is MIT licensed and its source code is available on GitHub. The web version is hosted on Cloudflare Pages’ free tier, with serverless functions serving the ASCII output. The tool is suitable for anyone interested in astronomy or visual representations of lunar cycles, and is designed to operate efficiently within web and terminal environments.