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astroquery-mcp is an MCP server that lets your AI assistants, like Claude and Codex, search astronomy data for you. Ask a question in plain language, and the assistant can look up objects, find telescope observations, pull catalog data and search the research literature from the following archives:

• SIMBAD
• NED
• VizieR
• ADS
• MAST Observations
• MAST Catalogs
• HEASARC
• IRSA
• NASA Exoplanet Archive
• Gaia
• SDSS
• ALMA
• ESA Hubble
• ESA JWST
• XMM-Newton

Installation

git clone https://github.com/NASA-IMPACT/astroquery-mcp.git
cd astroquery-mcp
uv sync

Run locally

You can run this MCP server locally from the code you just cloned. This starts it at http://127.0.0.1:8000/mcp:

uv run fastmcp run server.py --transport http --port 8000

To use a different port (for example, when 8000 is already in use), change --port. The URL changes to match, e.g. --port 9000 gives http://127.0.0.1:9000/mcp.

Point any MCP client that supports HTTP servers at that URL. For example, in Claude Code:

claude mcp add --transport http astroquery http://127.0.0.1:8000/mcp

Authentication

Service	Environment variable	Needed for
NASA ADS	API_DEV_KEY	All ADS queries
MAST	MAST_TOKEN	Proprietary MAST data only

Set them in your shell before starting the server:

export API_DEV_KEY="your-ads-token"
export MAST_TOKEN="your-mast-token"

Use the astroquery_check_auth tool to see which tokens the server picked up.

Typical workflow

astroquery_list_modules()                              # which archives exist
astroquery_list_functions("simbad")                    # which functions SIMBAD has
astroquery_get_function_info("simbad", "query_object") # parameters of one function
astroquery_execute("simbad", "query_object", {"object_name": "M31"})

Special parameter handling in astroquery_execute:

• Coordinates can be an object name ("M31") or {"ra": 10.68, "dec": 41.27} (degrees).
• Radius can be a number (arcmin) or {"value": 5, "unit": "arcmin"}.

Links

• Source: github.com/NASA-IMPACT/astroquery-mcp
• Issues: github.com/NASA-IMPACT/astroquery-mcp/issues