moonphasetimed

Moonphasetimed is an open‑source command‑line utility and API library designed to calculate the precise timing of lunar phases for any geographic location and time zone. It uses the short‑term lunar ephemeris developed by the United States Naval Observatory, providing phase times accurate to within a few seconds over the next 10 years. The tool outputs data in plain text, JSON, or XML formats, making it suitable for integration into web services, mobile applications, and scientific workflows.

Core functionality includes calculating sunrise, sunset, dawn, and dusk times in conjunction with lunar phases, generating calendar entries for new moons, first quarter moons, full moons, and last quarter moons. Users can specify date ranges, offsets, and the desired epoch (e.g., UTC or local time). The library is available in Python, Rust, and JavaScript, and exposes a simple API for fetching phase data programmatically.

Typical usage involves invoking the binary with a location in latitude and longitude and optionally a time zone. For example, “moonphasetimed --lat 37.7749 --lon -122.4194 --start 2026-01-01 --end 2026-01-07 --format json” returns the exact times of all primary phases for San Francisco over one week. Developers can embed the library into scheduling tools, astronomy applications, or IoT devices that require lunar-aware timing.

Moonphasetimed is distributed under the MIT license, encouraging commercial and non‑commercial use. The project is hosted on GitHub, with an active issue tracker and contribution guidelines. It links to related astronomical software such as PyEphem and the USNO Circulars, and is listed in the Python Package Index and npm registry.