API v2.1.0 · MCP v0.8 · 23 tools live

Sky data for developers
and AI agents.

Positions, moon phases, rise & set, scientific ephemerides, natal charts and astronomical events — clean JSON over HTTPS, plus a hosted MCP server your agents can call directly.

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Free tier · 50 requests/month · no credit card

{ }

REST API

29+ endpoints across snapshots, bodies, ephemerides, events, locations and catalogs. A predictable { data, meta } envelope on every call.

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Hosted MCP

23 named tools at mcp.astronomycore.com. Point Cursor or Claude Desktop at it — no local install.

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Free to start

50 requests/month on the free plan, every feature flag enabled. Generate a key and ship in a minute.

One request

Ask the sky a question.

Pass a latitude, longitude and time. Get back exactly the fields you asked for — nothing to parse, nothing to compute locally.

~120ms

median response

5044

catalog stars

IAU constellations

moon.sh

curl -H "Authorization: Bearer ac_live_..." \
  "https://api.astronomycore.com/v1/bodies/moon\
   ?latitude=41.9&longitude=12.5"

# → { "phase": "Waxing Gibbous",
#     "illumination": 0.78,
#     "rise": "14:21Z", "set": "01:48Z" }

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