Gravity falls off with distance: g(r) = g₀ R² / r², with μ = g₀R². The ball follows a Kepler conic between impacts. Circular speed at radius r is v_c = √(μ/r), escape speed is √2 · v_c, and a low orbit lasts T = 2π √(r³/μ).
Each impact reverses the normal velocity component with restitution e: v_n' = −e v_n, and keeps 95% of the tangential component (rolling friction). Rebound height after a vertical drop scales as e² because h' = e² h. Specific energy ε = v²/2 − μ/r is constant in flight and falls by a factor e² of the normal kinetic part at each bounce.
Integration: velocity Verlet with a step small relative to the local orbital time, impacts located by interpolation on the step.
Simplifications: point ball, perfectly spherical non-rotating airless body, no spin or friction model beyond the fixed tangential loss, single body (no moon or tidal effects), flat-ground heights are not shown. Altitude is measured from the surface; sizes in the drawing are exaggerated.