Escape & Orbital Velocity

Escape et circular orbital speed at altitude, avec body presets

About this tool

Speed needed to escape a body's gravity from radius r:

  • v_e = √(2GM/r) — escape (parabolic) velocity
  • v_c = √(GM/r) — circular orbital velocity at the same r
  • v_e / v_c = √2 ≈ 1.4142
  • Surface gravity: g = GM/R²

Pick a body preset to fill mass and equatorial radius. Add an altitude to compute escape and orbital speed at that altitude.

Reference values

Earth surface: v_e ≈ 11.186 km/s, v_c ≈ 7.910 km/s. Sun surface: v_e ≈ 617.5 km/s. Moon surface: v_e ≈ 2.376 km/s.