Astronomy
Light-Year and Astronomical Unit Converter
Convert between light-years (ly), parsecs (pc), astronomical units (AU), kilometers and meters using IAU-defined constants, with a parallax-angle → distance helper.
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Quick start
Call this tool from your code in three languages.
cURL
curl -X POST 'https://api.elysiatools.com/en/api/tools/light-year-and-astronomical-unit-converter' \
-H 'Content-Type: application/json' \
-d '{"value":1,"fromUnit":"ly","decimals":6,"scientific":false,"parallax":"e.g. 0.7685 (Proxima Centauri)"}'API reference
Send a POST request with your inputs as JSON. File parameters require a separate upload first.
Endpoint
HTTP
POST https://api.elysiatools.com/en/api/tools/light-year-and-astronomical-unit-converterParameters
| Name | Type | Required | Description |
|---|---|---|---|
| value | number | Yes | The distance value to convert. |
| fromUnit | select | No | The unit of the value you entered. |
| decimals | number | No | Number of digits after the decimal point in the result. |
| scientific | checkbox | No | Display results in scientific (exponential) notation. |
| parallax | text | No |
MCP integration
Add this tool to your Model Context Protocol server so AI agents can list and call it.
Server configuration
Add this block to your MCP client configuration:
mcp.json
{
"mcpServers": {
"elysiatools-light-year-and-astronomical-unit-converter": {
"name": "light-year-and-astronomical-unit-converter",
"description": "Convert between light-years (ly), parsecs (pc), astronomical units (AU), kilometers and meters using IAU-defined constants, with a parallax-angle → distance helper.",
"baseUrl": "https://api.elysiatools.com/mcp/sse?toolId=light-year-and-astronomical-unit-converter",
"command": "",
"args": [],
"env": {},
"isActive": true,
"type": "sse"
}
}
}List available tools
After connecting to the SSE endpoint, list the exposed tools:
tools/list
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/list"
}Call this tool
Invoke the tool by its id, passing arguments built from its parameters:
tools/call
{
"jsonrpc": "2.0",
"id": 2,
"method": "tools/call",
"params": {
"name": "light-year-and-astronomical-unit-converter",
"arguments": {
"value": 1,
"fromUnit": "ly",
"decimals": 6,
"scientific": false,
"parallax": "e.g. 0.7685 (Proxima Centauri)"
}
}
}Chain multiple tools in one session with a comma-separated toolId list, e.g. /mcp/sse?toolId=png-to-webp,jpg-to-webp,gif-to-webp (max 20).
Questions or issues? Contact [email protected]