Astronomy MCP Server vs MCP Ephemeris

In-depth architectural comparison of the Astronomy MCP Server and MCP Ephemeris MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

Which MCP Server Should You Choose?

Choose Astronomy MCP Server when:

• You need dedicated capabilities in the Aerospace & Astrodynamics domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• You have access to required keys: ASTRONOMY_ENABLE_HORIZONS.
• Primary tools included: astronomy_get_sky_position, astronomy_get_rise_set, astronomy_get_moon_phase.

Explore Astronomy MCP Server Details

Choose MCP Ephemeris when:

• You need dedicated capabilities in the Aerospace & Astrodynamics domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• Primary tools included: get_planet_positions, get_moon_phase, get_current_sky.

Feature & Specification Comparison

Specification	Astronomy MCP Server Aerospace & Astrodynamics	MCP Ephemeris Aerospace & Astrodynamics
Summary	Offline observational astronomy: positions, rise/set, moon phases, eclipses, and seasons.	NASA-validated computed planetary positions for your AI — 19 astrology tools, never hallucinated.
Category & Scope	Aerospace & Astrodynamics	Aerospace & Astrodynamics

Tools & Capabilities Breakdown

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

{
  "mcpServers": {
    "astronomy-mcp-server": {
      "command": "bunx",
      "args": [
        "@cyanheads/astronomy-mcp-server@latest"
      ],
      "env": {
        "ASTRONOMY_ENABLE_HORIZONS": "YOUR_ASTRONOMY_ENABLE_HORIZONS_HERE"
      }
    }
  }
}

{
  "mcpServers": {
    "mcp-ephemeris": {
      "command": "npx",
      "args": [
        "-y",
        "@cosmosos/mcp-ephemeris"
      ]
    }
  }
}

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