Hosted in production (no setup needed): https://mcp.io-aerospace.org/
SSE endpoint: https://mcp.io-aerospace.org/sse
Note: Most MCP clients that support HTTP/SSE only need the base URL; they will connect to the SSE stream internally (commonly at
/sse
). The explicit/sse
URL is provided here for manual/web integrations.
A Model Context Protocol (MCP) server for aerospace and astrodynamics calculations, providing tools for celestial body ephemeris, orbital mechanics, and space mission analysis.
This MCP server provides two transport options:
- STDIO Transport: Standard input/output communication (recommended for MCP clients)
- SSE Transport: HTTP Server-Sent Events for web-based integrations
The server includes comprehensive tools for:
- Celestial body ephemeris and state vector calculations
- Orbital mechanics and geometry computations
- Deep Space Network (DSN) ground station operations
- Solar system object properties and characteristics
- Mathematical conversions for aerospace calculations
- Time system conversions and utilities
This server is powered by the IO Aerospace Astrodynamics framework, which provides the core algorithms for ephemerides, orbital mechanics, geometry, and time systems.
You can start integrating immediately against the production instance:
- Base URL: https://mcp.io-aerospace.org/
- SSE stream: https://mcp.io-aerospace.org/sse
Example (browser/Node):
const eventSource = new EventSource('https://mcp.io-aerospace.org/sse');
eventSource.onmessage = (event) => {
console.log('message', event.data);
};
eventSource.onerror = (err) => {
console.error('sse error', err);
};
Self-hosting is optional; see below for Docker and .NET instructions.
mcp-server/
├── AI/ # AI tools and models
│ ├── Tools/ # Core calculation tools
│ ├── Models/ # Data models and types
│ └── Converters/ # Type converters
├── Data/ # Data providers and solar system kernels
│ ├── SolarSystem/ # SPICE kernel files
│ └── SolarSystemObjects/ # Celestial body definitions
├── Server.Sse/ # HTTP/SSE transport server
├── Server.Stdio/ # STDIO transport server
├── docker-compose.yml # Development Docker configuration
├── docker-compose.prod.example.yml # Production template
└── deploy-production.sh # Production deployment script
- .NET 9.0 SDK or runtime
- Docker (for containerized deployment)
- Solar system kernels data (SPICE kernels)
- GetEphemerisAsStateVectors: Calculate state vectors (position and velocity) of celestial bodies
- GetCelestialBodyProperties: Retrieve geophysical properties of planets and moons
- ConvertStateVectorToKeplerianElements: Convert state vectors to Keplerian orbital elements
- ConvertStateVectorToEquinoctialElements: Convert state vectors to equinoctial elements
- ConvertStateVectorToEquatorialCoordinates: Convert state vectors to equatorial coordinates
- ConvertKeplerianElementsToStateVector: Convert Keplerian elements back to state vectors
- ConvertEquinoctialElementsToStateVector: Convert equinoctial elements back to state vectors
- ConvertStateVectorToTheGivenFrame: Transform state vectors between reference frames
- FindCoordinateConstraint: Find time windows when coordinate constraints are met
- FindDistanceConstraint: Find time windows when distance constraints are satisfied
- FindOccultingConstraint: Find occultation and eclipse events
- GetDeepSpaceStationPlanetodeticCoordinates: Get latitude, longitude, and altitude of DSS stations
- GetDeepSpaceStationStateVector: Calculate state vectors for ground stations
- GetHorizontalCoordinates: Get azimuth and elevation from ground stations
- GetDSSFrame: Retrieve reference frame information for DSS stations
- ConvertDateTime: Convert between different time systems (UTC, TDB, TAI, TDT, GPS)
- CurrentDateTime: Get current UTC date and time
- DegreesToRadians / RadiansToDegrees: Angular unit conversions
- ConvertDegreesToHours / ConvertHoursToDegrees: Time-angle conversions
- DegreesToArcseconds / ArcsecondsToDegrees: Angular precision conversions
- RadiansToArcseconds / ArcsecondsToRadians: Angular unit conversions
- MetersToMiles / MilesToMeters: Distance unit conversions
- MetersToFeet / FeetToMeters: Distance unit conversions
- MetersToKilometers / KilometersToMeters: Metric distance conversions
- MetersToAstronomicalUnits / AstronomicalUnitsToMeters: Astronomical distance conversions
- MetersToParsec / ParsecToMeters: Stellar distance conversions
- MetersToLightYears / LightYearsToMeters: Cosmic distance conversions
git clone https://github.com/IO-Aerospace-software-engineering/mcp-server
cd mcp-server
docker-compose up
The SSE server will be available at http://localhost:8080
.
- Copy
docker-compose.prod.example.yml
todocker-compose.prod.yml
- Update the domain names in the production file
- Ensure kernel data exists at
./data/solarsystem/
- Deploy using the automated script:
./deploy-production.sh
git clone https://github.com/IO-Aerospace-software-engineering/mcp-server
cd mcp-server
dotnet build
The server requires SPICE kernels for solar system calculations.
- STDIO server configuration (no appsettings):
- Provide the kernels path via CLI or environment variable
- Priority: CLI flag > IO_DATA_DIR environment variable
- CLI flags:
-k <path>
,--kernels <path>
, or--kernels-path <path>
Examples:
# Using CLI flag
./Server.Stdio -k /path/to/your/spice/kernels
# Using environment variable (Linux/macOS)
export IO_DATA_DIR="/path/to/your/spice/kernels"
./Server.Stdio
# Windows (PowerShell)
$env:IO_DATA_DIR="C:\path\to\your\spice\kernels"
./Server.Stdio.exe
- SSE server configuration: may use appsettings.json as before.
Required Kernel Files:
kernels/
├── de440s.bsp # Planetary ephemeris
├── latest_leapseconds.tls # Leap seconds
├── pck00011.tpc # Planetary constants
├── earth_latest_high_prec.bpc # Earth orientation
└── ... # Additional kernel files
- Release assets are native executables per OS/RID (no ZIP). Filenames:
- mcp-server-stdio--linux-x64
- mcp-server-stdio--win-x64.exe
- mcp-server-stdio--osx-arm64
- On macOS, a sidecar native library may be provided (e.g., libIO.Astrodynamics.so). Place it in the same directory as the executable.
# After publishing or downloading a release asset for your OS
./Server.Stdio -k /path/to/kernels
cd Server.Sse
dotnet run
# Server available at http://localhost:8080
- File:
docker-compose.yml
- Ports: 8080 (HTTP), 8081 (HTTPS)
- Data: Mounted from
./Data/SolarSystem
- Usage:
docker-compose up
- File:
docker-compose.prod.yml
(create from example) - Features: Traefik reverse proxy, optimized images
- Data: Host-mounted from
./data/solarsystem
- Deployment: Automated via
deploy-production.sh
Note: Many MCP clients use JSON-based configuration files, but schemas differ per client. The JSON examples below use Claude Desktop’s schema; adapt keys to your client’s format.
Add to your Claude Desktop configuration:
{
"mcpServers": {
"astrodynamics": {
"command": "/path/to/Server.Stdio",
"args": ["-k", "/path/to/kernels"]
}
}
}
Alternatively, set an environment variable if your client supports it:
{
"mcpServers": {
"astrodynamics": {
"command": "/path/to/Server.Stdio",
"args": [],
"env": {
"IO_DATA_DIR": "/path/to/kernels"
}
}
}
}
Use your production server over HTTP/SSE by specifying the base URL only:
{
"mcpServers": {
"astrodynamics": {
"transport": {
"type": "http",
"url": "https://mcp.io-aerospace.org"
}
}
}
}
- Only the base URL is required; the client will use the SSE stream internally (commonly at
/sse
). - This schema is for Claude Desktop; other clients may use different keys.
- Provide the base URL: https://mcp.io-aerospace.org
- Add headers (e.g., Authorization) only if your deployment requires it
- Don’t append
/sse
unless your client documentation requires it; most discover the SSE path - Refer to your client’s documentation for the exact JSON schema or settings UI
Using the MCP SDK to connect to the hosted server and list tools:
import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { HttpClientTransport } from "@modelcontextprotocol/sdk/client/transport/http.js";
const transport = new HttpClientTransport(new URL("https://mcp.io-aerospace.org"));
const client = new Client(
{ name: "example-client", version: "1.0.0" },
{ capabilities: { tools: {}, prompts: {}, resources: {} } },
transport
);
await client.connect();
const tools = await client.listTools();
console.log("Tools:", tools);
// Example: call a tool
// const result = await client.callTool({ name: "GetEphemerisAsStateVectors", arguments: { /* ... */ } });
// console.log(result);
If this project helps your work, please consider sponsoring ongoing development, hosting, and data updates.
- Sponsor page: https://github.com/sponsors/IO-Aerospace-software-engineering
- Businesses: open an issue to discuss invoices or custom arrangements
Your support helps keep the hosted server online and the SPICE data current.
- "Kernels directory does not exist": Verify the path passed with
-k
(orIO_DATA_DIR
) exists and contains SPICE files - "Failed to load kernel": Ensure all required kernel files are present and accessible
- Connection errors: Check firewall settings and port availability
# Development
docker-compose logs -f
# Production
docker logs -f container-name
- Fork the repository
- Create your feature branch (
git checkout -b feature/amazing-feature
) - Commit your changes (
git commit -m 'Add amazing feature'
) - Push to the branch (
git push origin feature/amazing-feature
) - Open a Pull Request
This project is licensed under the MIT License - see the LICENSE file for details.
For support and questions:
- Create an issue on GitHub
- Check the troubleshooting section above
- Review the deployment guide in DEPLOYMENT_GUIDE.md
Sylvain
New: A step-by-step How To guide is available:
- Markdown: docs/HowTo.md
- HTML (full): docs/howto.html
- HTML (compact): docs/howto-mini.html