ephemeris.fyi - Astronomical and astrological MCP server

What is This?

This is a totally free remote Model Context Protocol (MCP) server and API that provides ephemeris data for celestial bodies. MCP provides a standardized way to connect AI models to different data sources and tools.

Our server offers 11 specialized tools for astronomical and astrological calculations, accessible by AI assistants like Claude, ChatGPT, and other MCP-compatible applications.

Using the MCP Server

With Claude (Web & Desktop)

Add this remote MCP server to Claude through your web interface:

Go to Claude.ai Settings > Integrations
Click "Add custom integration"
Enter the server URL: https://ephemeris.fyi/mcp
Click "Add" to complete the configuration

Requirements: Available for Claude Pro, Max, Team, and Enterprise plans (currently in beta)

With Cursor IDE

Click the button below to add the server to Cursor:

Alternatively, add this remote MCP server to Cursor IDE:

Go to Settings > Cursor Settings
Enable "MCP servers"
Create or edit .cursor/mcp.json in your project (or ~/.cursor/mcp.json for global access)
Add the following configuration:

{
  "mcpServers": {
    "ephemeris": {
      "url": "https://ephemeris.fyi/mcp"
    }
  }
}

With Other MCP Clients

Connect to our MCP server at:

https://ephemeris.fyi/mcp

Our server uses StreamableHTTP transport with JSON-RPC 2.0 for stateless communication.

Available Tools

get_ephemeris_data - Complete ephemeris data for multiple bodies
get_single_body_position - Position data for one celestial body
get_current_sky - All celestial bodies for current time/location
get_planetary_positions - Planets only (excluding sun/moon)
get_luminaries - Sun and moon positions only
calculate_aspects - Astrological aspects between bodies
get_moon_phase - Moon phase and illumination data
get_daily_events - Rising, culmination, and setting times
get_zodiac_sign - Zodiac sign and degree for positions
compare_positions - Compare positions between two dates
get_earth_position - Earth's heliocentric coordinates

Supported Bodies: mercury, venus, mars, jupiter, saturn, uranus, neptune, pluto, sun, moon, chiron

REST API (Alternative)

If you prefer traditional REST API calls, all MCP tools are also available as REST endpoints:

			# Get sun position
GET /ephemeris/get_single_body_position?body=sun&latitude=40.7128&longitude=-74.0060&datetime=2025-01-01T12:00:00Z

# Get multiple bodies
GET /ephemeris/get_ephemeris_data?bodies=sun,moon,mars&latitude=40.7128&longitude=-74.0060&datetime=2025-01-01T12:00:00Z

# Calculate aspects
GET /ephemeris/calculate_aspects?bodies=sun,moon,mars&latitude=40.7128&longitude=-74.0060&datetime=2025-01-01T12:00:00Z
		

Full API documentation is available in our OpenAPI specification.

Example Use Cases

Astronomical Research: Precise celestial body positions for scientific calculations
Observational Astronomy: Planning observations with rise/set times and current sky data
Astrological Applications: Birth chart calculations and aspect analysis
Educational Tools: Teaching astronomy and celestial mechanics
AI-Powered Analysis: Letting AI assistants interpret celestial data
Mobile & Web Apps: Integrating ephemeris data into applications

About

Created by Matt Kane. This open-source project is available on GitHub.

This service is powered by the Moshier Ephemeris JS library, which implements Steve L. Moshier's astronomical ephemeris calculations in JavaScript. The Moshier Ephemeris provides high-precision planetary and lunar positions based on established astronomical algorithms.