Artemis II Live Tracker

A real-time LED strip + phone dashboard that tracks NASA's Artemis II spacecraft on its journey to the Moon and back, using live telemetry from JPL Horizons.

Built during the live mission (April 1-11, 2026) as a family weekend project.

What It Does

• 60-LED strip shows spacecraft position between Earth and Moon in real-time
• Android phone dashboard displays live stats, milestone countdowns, and AI-generated fun facts
• Startup animation — rocket flies from Earth to current position on each power-on
• Phase-aware effects — different visuals for outbound, lunar flyby, return, reentry, and splashdown
• Fully autonomous — plug in power, everything starts automatically

Hardware

Component	Details
Raspberry Pi 5	Running the tracker software
WS2812 LED Strip	60 LEDs, 1m, 5V, addressable RGB
Android Phone	Samsung Galaxy A13 (any Android with USB debugging works)
5V Power Supply	4A+ for Pi + LED strip
3D Printed Channel	LED diffuser with translucent PETG cap

Wiring

Pi GPIO 10 (SPI MOSI, Pin 19) → LED Strip DIN
Pi Pin 2 (5V)                  → LED Strip VCC
Pi Pin 6 (GND)                 → LED Strip GND
Phone                          → Pi USB port (ADB)

LED Effects

[Earth 🔵🔵🔵] · · · · ★🚀🔴🟠🟡· · · · · · [🌕🌕🌕 Moon]
  bright blue                                   bright white
  3 LEDs          rocket + exhaust plume         3 LEDs

Phase	Effect
Outbound	Blue-white capsule + red/orange/yellow exhaust plume
Flyby	Blue shimmer near Moon, golden pulse when distance record broken
Return	Comet tail flips direction
Reentry	Fireball mode — red-hot rapid flicker, heat glow on Earth end
Splashdown	Rainbow celebration → ocean breathing → trophy mode

Phone Dashboard

Space-themed fullscreen dashboard via FastAPI + WebSocket:

• Live distance from Earth/Moon, speed, MET
• Mission progress bar
• Next milestone countdown with emoji timeline
• AI-powered fun facts (Gemini API, refreshed hourly)

Data Source

JPL Horizons API — NASA's authoritative ephemeris system. The spacecraft is tracked as ID -1024. No API key needed. Polled every 5 minutes with exponential backoff on failure and position interpolation between polls.

Quick Start

On the Raspberry Pi 5

# Clone
git clone https://github.com/stepankaiser/artemis-tracker.git
cd artemis-tracker

# Setup (installs Python venv, LED/OLED libraries, enables SPI/I2C)
bash setup_pi.sh

# Run in demo mode (simulates full mission in 2 minutes)
source .venv/bin/activate
python -m artemis --demo

# Run live (real Artemis II data)
python -m artemis

Phone Display

Connect an Android phone with USB debugging enabled:

bash setup_phone.sh

Auto-Start on Boot

sudo cp artemis-tracker.service /etc/systemd/system/
sudo cp artemis-phone.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable artemis-tracker artemis-phone

Project Structure

artemis/
├── tracker.py        # Main loop — 30fps LED rendering, 1Hz display updates
├── horizons.py       # JPL Horizons API client with interpolation & backoff
├── leds.py           # LED effects engine — all mission phases
├── display.py        # SSD1306 OLED driver (optional, if you have one)
├── web.py            # FastAPI + WebSocket server for phone dashboard
├── dashboard.html    # Space-themed responsive dashboard
├── facts.py          # Gemini-powered fun fact generator
└── config.py         # Mission timeline, milestones, crew data

Raspberry Pi 5 Notes

The Pi 5 uses the RP1 I/O chip which changes how SPI and I2C work:

• SPI: Device is /dev/spidev10.0 (not spidev0.0). Pins must be set to alt function with pinctrl set 10 a0 before each start.
• I2C: Hardware I2C may be on bus 1 or 3 depending on overlays. The code auto-detects.
• LED Library: Uses adafruit-circuitpython-neopixel-spi (the classic rpi_ws281x doesn't work on Pi 5).

Mission Timeline

Event	Date (UTC)	Status
Launch	Apr 1, 22:35	Completed
TLI Burn	Apr 2, 23:49	Completed
Lunar SOI Entry	Apr 6, 04:43	Upcoming
Lunar Flyby (6,513 km)	Apr 6, 23:06	Upcoming
Max Distance Record	Apr 6, 23:09	Upcoming
Splashdown	Apr 11, 00:17	Upcoming

Built With

• Python 3.13, FastAPI, uvicorn
• adafruit-circuitpython-neopixel-spi
• JPL Horizons API
• Google Gemini API (fun facts)
• Bambu Lab A1 Mini (3D printed LED channel)

License

MIT

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Built with a lot of excitement during the Artemis II mission by Stepan Kaiser and family, with help from Claude Code.