Astronomy Oracle is an astronomical catalog and observation planning MCP server for LLM assistants, whose main purpose is to provide accurate astronomical catalog data and observation session planning, avoiding hallucinations by large language models regarding magnitudes, coordinates, and visibility.
Main capabilities include:
- Built-in more than 13,000 deep-sky objects, from the OpenNGC catalog, covering NGC, IC, Messier, and appendices objects.
- Provides 3 tools: object lookup, catalog search, and observation session planning.
- Object lookup: look up objects by Messier number, NGC/IC number, or common name, and optionally calculate visibility based on a given location and time. Returns detailed data, including type, coordinates (right ascension/declination), magnitude, angular size, surface brightness, Hubble type, cross-references, and, when a location is provided, current altitude/azimuth and rise/transit/set times.
- Catalog search: search and filter the catalog by type, constellation, magnitude range, angular size, or catalog membership. Returns a table of matching objects sorted by brightness, supporting filtering by object type (galaxies, planetary nebulae, open clusters, etc.), constellation, magnitude range, minimum angular size, and catalog (Messier, Caldwell, NGC, IC).
- Observation session planning: generate an observation plan for a given location and date, returning the best observable objects grouped by time window. Results are divided into three windows (evening, midnight, before dawn), and observability is scored based on altitude, magnitude, and angular size.
Usage:
- Can be run directly via npx.
- Can also be installed globally.
- Add it to claude_desktop_config.json for configuration.
Technical features:
- Deterministic astronomical mathematical calculations, including Julian day, sidereal time, horizontal coordinate conversion, rise/transit/set times.
- Zero network dependency, all data is packaged, and all calculations are performed locally.
Applicable scenarios:
- LLM assistant applications that need accurate astronomical data.
- Astronomical observers planning observation sessions.
- Querying detailed information and visibility of deep-sky objects.
Limitations:
- The materials do not provide more information about fees, pricing, platform support scope, performance guarantees, or specific usage steps.
- Data licensing: OpenNGC data uses the Creative Commons Attribution-ShareAlike 4.0 International License, and the code uses the MIT license.
