Escape Velocity

How this simulation works

Use the Launch Speed slider to set how fast the projectile leaves the planet surface (in m/s). Use the Planet Radius slider to change the planet's size — a smaller, denser planet has a higher escape velocity. Press Start to launch the projectile radially upward and watch it either slow, stop, and fall back, or escape entirely. Press Pause to freeze the motion mid-flight and Resume to continue. Press Reset to return the projectile to the surface with the current slider settings. Compare the Speed readout to the v_esc readout to see whether your launch will escape.