
Connects Claude to NASA's JPL Horizons system for querying solar system body positions and trajectories. Exposes four tools: lookup to resolve object names to SPK identifiers, ephemeris for generating position tables, and convenience wrappers for observer and vector table types. Useful when you need precise celestial coordinates, orbital data, or want to calculate positions of planets, asteroids, comets, or spacecraft at specific times. Hosted by Pipeworx as a streamable HTTP endpoint, so no local setup required. Can be used standalone or as part of the larger Pipeworx gateway with 673+ data sources. Includes an ask_pipeworx natural language interface that handles tool selection automatically.
NASA JPL Horizons MCP — solar-system body ephemerides (planets, moons, asteroids, comets, spacecraft). Keyless.
Part of Pipeworx — an MCP gateway connecting AI agents to 1476+ live data sources.
lookup(query) — resolve an object name → SPK idephemeris(command, center?, start_time, stop_time, step_size?, table_type?) — generate ephemeridesobservers(command, center?, start_time, stop_time, step_size?) — observer (apparent position) tablevectors(command, center?, start_time, stop_time, step_size?) — Cartesian state vectorscommand accepts SPK id (e.g. "499" Mars), name "Mars", or designation.
center defaults to "500@399" (geocentric).
https://ssd.jpl.nasa.gov/api/horizons.api and /horizons_lookup.api.
Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):
{
"mcpServers": {
"horizons-nasa": {
"url": "https://gateway.pipeworx.io/horizons-nasa/mcp"
}
}
}
tools/list at https://gateway.pipeworx.io/horizons-nasa/mcp returns the tools in the table
above plus the shared Pipeworx meta-tools — ask_pipeworx,
discover_tools, search_within, remember/recall and the rest of the
gateway-wide set. So the tool count you see is larger than this table: a
single-pack endpoint currently lists roughly 30 shared tools alongside the
pack's own. The connection's initialize response states its exact scope, and
is the authoritative answer for a given day.
This is deliberate, not multiplexing by accident. The meta-tools are what let a
scoped connection answer a question this pack does not cover — via
ask_pipeworx, which routes across the whole catalog — without you adding a
second MCP server. There is currently no way to mount a pack endpoint without
them; if the extra schemas cost you more context than the routing is worth,
connect to the full gateway once rather than to several pack endpoints.
Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:
{
"mcpServers": {
"pipeworx": {
"url": "https://gateway.pipeworx.io/mcp"
}
}
}
Both URLs reach the same gateway and the same 1476+ data sources. The
only difference is which pack's tools are listed directly; ask_pipeworx
reaches all of them from either one.
Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:
ask_pipeworx({ question: "your question about Horizons Nasa data" })
The gateway picks the right tool and fills the arguments automatically.
MIT