☿️ Mercury Perihelion Precession Lab: Einstein's 43 Arcsecond Test (2D)

Mercury's orbit does not close: general relativity adds 43 arcseconds per century to its perihelion. Compare Newton, first-order relativity and the exact Schwarzschild orbit, with exaggeration, an eccentricity sweep and independent checks.

2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install