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The inner solar system, to scale

Real masses, real perihelion distances, real perihelion speeds, and Newton's G converted into scene units — one length unit is a million kilometres, one mass unit is 10^23 kg, one second is three hours. Nothing is tuned to make the orbits close: each planet is released at its measured perihelion with its measured speed, and the ellipse that follows is whatever the equation produces. Mercury's eccentricity, Earth's near-circle and Mars's 687-day year all fall out of it. Only the globes are big.