What started as a broken AI Studio zip file export with unmounted tracking components and unused dependencies evolved into a high-precision orbital mechanics laboratory. The initial recon pass was simply about getting a spacecraft speed visualizer back online, but as I pulled out the unused code, the potential for a proper telemetry deck became obvious.

This project serves as Paradigm 2 in the broader Cartography project, exploring the Leaflet rendering pipeline. By pushing Web Mercator to its limits, I wanted to build an interactive dashboard that didn't just plot a line on a map, but modeled the raw physics of orbital re-entry and exposed the inherent geographical distortions of flat maps.

What It Does

Artemis Velocity Vis is an interactive Leaflet map that acts as a real-time flight telemetry dashboard. It features:

• 4 Flight Presets: Trans-Lunar Return, Trans-Eurasian Orbit Pass, Trans-Continental Sprint, and Equatorial Geodesic Ring.
• Continuous Velocity Scrubber: Scale seamlessly from 500 mph (subsonic) all the way to 25,000 mph (orbital re-entry).
• Live Mach Telemetry: Real-time computation of Mach number based on current velocity ($M = v / 767.26$).
• Distortion Analysis: An interactive toggle comparing the true spherical geodesic arc against a naïve flat Mercator chord to visualize path error.
• Multi-Theme Telemetry Deck: Switch instantly between E-Ink Electronic Paper, NASA Mission Control Dark, and ESRI Satellite Reconnaissance themes.

Technical Details

Under the hood, the simulator replaces linear interpolation with true spherical mathematics and GPU optimization:

• Spherical Slerp Interpolation: Used to calculate precise great-circle arcs across the globe.
• Haversine Formula: The core math powering the spherical geodesic distances: $\Delta\sigma = 2 \arcsin\left(\sqrt{\sin^2\left(\frac{\Delta\phi}{2}\right) + \cos\phi_1\cos\phi_2\sin^2\left(\frac{\Delta\lambda}{2}\right)}\right)$
• GPU-accelerated CSS Tile Filters: Powers the instant theme switching without re-rendering or refetching map tiles.
• Camera Tracking: Real-time heading vector alignment that keeps the telemetry camera synchronized with the flight path.
• Catmull-Rom Spline: Models the dynamic altitude profiling required for a trans-lunar skip entry.

What I Learned

Working with Leaflet means accepting Web Mercator's distortions, but it also gives you a canvas to challenge them. The geodesic vs. chord comparison makes that distortion visibly and mathematically tangible. When you see a $+18.15\%$ path error on a Tokyo to NYC route—a difference of over a thousand miles—the lie of the flat map becomes the kind of thing you just can't unsee.