Space Launch & Starlink Tracker (MCP server)

Live MCP URL (Streamable HTTP, no auth): https://space-launch-tracker-mcp.vercel.app/mcp
Health check: https://space-launch-tracker-mcp.vercel.app/health

An MCP server that gives Grok Bot (or any MCP client) live space data:

• Upcoming launches worldwide with live countdowns, from The Space Devs Launch Library 2

• Starship status: next flights, recent flight outcomes and latest headlines (Launch Library 2 + Spaceflight News API)

• ISS / Tiangong / Hubble / any satellite pass predictions for any lat/lon, with naked-eye visibility

• Visible Starlink trains for any location

It uses CelesTrak TLEs and SGP4 via satellite.js. All data is public and needs no API keys. Every output cites its source URL and fetch timestamp.

Tools

tz takes any IANA timezone (for example Africa/Lagos). UTC is always shown alongside it.

Related MCP server: mcp-meteors

Example prompts

• "When's the next SpaceX launch and how long until liftoff? Show Lagos time."

• "What's the latest on Starship? When's the next flight?"

• "Can I see the ISS from London this week? When, and in which direction should I look?"

• "Any Starlink trains visible from New York in the next two nights?"

• "List the next 10 launches from anywhere in the world."

How it's calculated

• Passes: SGP4 propagation (satellite.js) at 20 s steps (30 s for Starlink), with rise and set refined to about 1 s by bisection. Accuracy is about ±1 min with fresh TLEs.

• Visible means the satellite is sunlit (cylindrical Earth-shadow model) and the sun is below −6° (civil twilight or darker) at the observer at maximum elevation.

• Sun position: low-precision Astronomical Almanac formula (~0.01°).

• Starlink "recent trains": satellites from the 6 most recent Starlink launches, by international designator. These are the low, bright trains people notice. mode: "all" checks up to 3,000 Starlinks, limited to 6 h.

Polite use of public APIs

• In-memory caching per URL:

  • Launch Library 2: 10 min. The free tier allows 15 requests per hour per IP. Set LL2_BASE_URL=https://lldev.thespacedevs.com/2.3.0 for development.

  • CelesTrak: 2 h, which is their requested minimum re-download interval.

  • Spaceflight News: 10 min.

• Concurrent identical requests are merged into one.

• If upstream fails or rate-limits (HTTP 429), the last cached copy is returned and clearly marked STALE.

• Requests send a descriptive User-Agent.

Run locally

npm install
npm test             # unit tests (vitest; mocked network)
npm run build
npm start            # Streamable HTTP at http://localhost:3000/mcp
npm run start:stdio  # stdio for desktop MCP clients
npm run smoke        # live: lists tools and calls every tool against the local HTTP server

Deploy to Vercel

1. Push to GitHub and import it at vercel.com/new (Framework preset: Other). No environment variables are required.

2. api/mcp.ts is the function. vercel.json rewrites /mcp to it. The MCP URL is https://<project>.vercel.app/mcp.

3. Check it with node scripts/smoke.mjs https://<project>.vercel.app/mcp.

The server is stateless with JSON responses. On serverless, the cache only lasts per warm instance. All Vercel functions share egress IPs, so if Launch Library 2 rate-limits the deployment, use a Space Devs API key: their Patreon tiers raise the limit. starlink_passes with mode: "all" is CPU-heavy, so keep the default mode on Hobby.

Testing instructions for marketplace reviewers

No credentials needed.

1. List tools. You should see 5.

2. upcoming_launches with {"limit": 5, "tz": "Africa/Lagos"}: a table of launches with T- countdowns and a "Source: The Space Devs Launch Library 2 … fetched " line.

3. starship_status with {}: next flights, recent flight outcomes and 5 linked headlines.

4. satellite_passes with {"lat": 51.5, "lon": -0.12, "hours": 120, "tz": "Europe/London"}: visible ISS passes with rise time, max elevation and direction. Add "visibleOnly": false to see every pass, with a reason when one isn't visible.

5. starlink_passes with {"lat": 40.71, "lon": -74.0, "hours": 48, "minElevationDeg": 15}: Starlink trains (or a clear "none visible" explanation).

6. Bad input, such as satellite_passes with {"lat": 100, "lon": 0}, returns a validation error.

Data sources and attribution

• The Space Devs, Launch Library 2

• Spaceflight News API

• CelesTrak (Dr. T.S. Kelso)

Predictions are for information only.

License

MIT