BOB VOYAGER — Forth ISS Orbital Oracle

Live ISS telemetry · Forth stack machine · WORM-sealed audit chain · Apache 2.0

"No syntax. Just a stack. NASA runs Forth. So does BOB."

NORAD 25544 · ISS ZARYA · SnapKitty Collective · 2026

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What it is

A real-time aerospace telemetry system tracking the International Space Station via a Forth stack machine. Every orbital calculation — vis-viva velocity, delta-v, orbital period, ground footprint — runs as a Forth word on a live stack. All telemetry is WORM-sealed with SHA-256 chained hashes.

Architecture

wheretheiss.at API
       ↓ (every 4.5s)
  src/server.mjs          ← Node.js backend (zero dependencies)
       ├── /api/telemetry  ← ISS position + full Keplerian elements + 6 ground stations
       ├── /api/worm       ← WORM chain audit log (last 50 seals)
       ├── /api/track      ← Historical positions (last 200 points)
       ├── /api/orbital    ← Pure orbital mechanics endpoint
       ├── /api/groundstations  ← Contact angles + distances to SF/JSC/TsUP/JAXA/ESA/Baikonur
       └── /api/health     ← Service status + WORM head
       ↓
  public/index.html        ← Forth interpreter + Canvas globe
  data/worm_chain.jsonl    ← Cryptographic audit log (append-only)
  data/telemetry.jsonl     ← Full telemetry history (append-only)

API Endpoints

Endpoint	Description
GET /api/telemetry	Live ISS position + orbital elements + ground station distances
GET /api/worm	Last 50 WORM chain entries (SHA-256 chained)
GET /api/track	Last 200 telemetry positions for orbit trail
GET /api/groundstations	SF · JSC · TsUP · JAXA · ESA · Baikonur contact status
GET /api/orbital	Keplerian elements (no external call)
GET /api/health	Service health + WORM count + uptime

Orbital Mechanics

All physics uses standard aerospace constants:

• μ = 398,600.4418 km³/s² (Earth gravitational parameter)
• Vis-Viva: v² = μ(2/r − 1/a)
• Period: T = 2π√(a³/μ)
• Inclination: 51.6° (ISS orbital plane)
• Eccentricity: 0.0001698 (near-circular)
• NORAD ID: 25544 (ISS ZARYA, launched 1998-11-20)

Forth Words (client)

Word	Description
ISS.LAT / LON / ALT / VEL	Push live ISS telemetry onto stack
ORBITAL.PERIOD	T = 2π√(r³/μ) in minutes
VIS.VIVA	Instantaneous orbital velocity (km/s)
SEMI.MAJOR	Semi-major axis (km)
MEAN.MOTION	Revolutions per day
APOGEE / PERIGEE	Orbit extremes (km)
FOOTPRINT	Ground visibility radius (km)
ECLIPSE	ISS in Earth shadow? (1/0)
DELTA.V	Delta-v to reboost to 420km nominal
DIST.SF / JSC / TSUP / JAXA	Distance to ground stations
ELEV.SF	Elevation angle from San Francisco
WORM.SEAL	Cryptographically seal top-of-stack

WORM Chain

Every telemetry update is cryptographically chained:

hash_n = SHA-256( hash_{n-1} | event | timestamp )

Written to data/worm_chain.jsonl. Append-only. Tamper-evident. Same principle as blockchain finality — applied to mission data.

Running

node src/server.mjs
# → http://localhost:4299

No npm install needed. Zero dependencies. Node 18+ only.

SEIT Educational Layer

BOB VOYAGER is deployed by Saint Errant Digital Institute (SEIT) as live aerospace curriculum.

A student types VIS.VIVA . → gets the actual orbital velocity of the ISS. They type DELTA.V . → see the fuel cost to raise the orbit. They type FOOTPRINT . → understand why ISS sees 2,800 km in every direction.

No textbook. No simulation. Real NORAD telemetry. Real physics. Real audit trail.

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Apache License 2.0 — SnapKitty Collective · Bel Esprit D'Accord Trust · 2026 snapkittywest.github.io · Evidence or Silence