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Launch Simulation
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Drop anything. On every planet. With real physics.
Free-fall calculator for all 9 planetary bodies — compute fall time, impact velocity & kinetic energy using each planet's real surface gravity.
Set your parameters and hit
Launch Simulation
With no air resistance, all objects fall identically regardless of mass. These are the exact kinematic equations this simulator uses.
d = distance (m) · g = gravity (m/s²) · t = time (s) · v = velocity (m/s)
Mass does not change how fast an object falls, but it does change how hard it hits. These values are computed from the exact impact velocity.
m = mass (kg) · h = drop height (m) · p = momentum
Using t = √(2h / g) for fall time and
v = g × t for impact velocity. Drop height h = 100 m, no air resistance.
| Planet | Gravity g (m/s²) | Fall Time (100 m) | Impact Velocity | Formula: t = √(200/g) |
|---|---|---|---|---|
| ☿ Mercury | 3.70 m/s² | 7.35 s | 27.2 m/s | √(200/3.70) |
| ♀ Venus | 8.87 m/s² | 4.75 s | 42.1 m/s | √(200/8.87) |
| 🌍 Earth | 9.81 m/s² | 4.52 s | 44.3 m/s | √(200/9.81) |
| ♂ Mars | 3.71 m/s² | 7.34 s | 27.2 m/s | √(200/3.71) |
| ♃ Jupiter | 24.79 m/s² | 2.84 s | 70.4 m/s | √(200/24.79) |
| ♄ Saturn | 10.44 m/s² | 4.38 s | 45.7 m/s | √(200/10.44) |
| ⛢ Uranus | 8.69 m/s² | 4.80 s | 41.7 m/s | √(200/8.69) |
| ♆ Neptune | 11.15 m/s² | 4.24 s | 47.2 m/s | √(200/11.15) |
| ♇ Pluto | 0.62 m/s² | 17.96 s | 11.1 m/s | √(200/0.62) |
Ideal free fall: constant surface gravity, no atmosphere. Run the simulator above to try other masses and heights.
Free fall is motion under gravity alone with no other forces. Without air resistance, every object — a feather or a bowling ball — falls with identical acceleration. Astronaut David Scott demonstrated this on the Moon in 1971 by dropping a hammer and a feather together.
Air density changes with altitude, so a single constant value is not accurate for tall drops. This simulator uses ideal free fall so every result follows exact equations that you can check by hand.
No. Fall time and impact velocity depend only on gravity and height. Mass changes only the kinetic energy and momentum at impact, so a heavier object hits harder but does not land sooner.
KE = ½mv² tells you the energy transferred at impact. A 1 kg object dropped 100 m on Earth hits with about 981 J. On Jupiter the same drop produces about 2,479 J because of the stronger gravity.
Jupiter's reference-level gravity of 24.79 m/s² is 2.53× Earth's. An object reaches 70+ m/s after a 100 m drop, while on Pluto (0.62 m/s²) it reaches only about 11 m/s.
This simulator uses the closed-form equations y = h − ½gt² and v = gt, not step-by-step approximation, so fall time and impact velocity are exact for constant gravity.
t = √(2h / g). For h = 100 m on Earth (g = 9.81): t = √(200 / 9.81) = 4.52 seconds. On Mars (g = 3.71): t = √(200 / 3.71) = 7.34 s. This formula assumes starting from rest (v₀ = 0).
g regardless of mass. Fall time t = √(2h / g) has no mass term. Heavier objects only hit with more kinetic energy and momentum.
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FreeFallLab uses planetary surface gravity values from NASA planetary fact sheets. Physics model: ideal free fall from rest with constant gravity and no air resistance, solved with exact closed-form equations (t = √(2h/g), v = gt). Gas giants use reference-level (1 bar) gravity. Not suitable for orbital mechanics or extreme-altitude calculations.