Calculate the gravitational attraction between two masses.
Gravitational force follows an inverse-square law, so doubling the separation quarters the force. Potential energy is negative by convention, approaching zero at infinite separation. The inverse-square relationship is why orbital altitude changes gravity far less than intuition suggests — at 400 km, gravity is still about 89 per cent of its surface value.
Gravitational Force
F = G m₁ m₂ ÷ r²
F = G m₁ m₂ ÷ r² Gravitational force follows an inverse-square law, so doubling the separation quarters the force. Potential energy is negative by convention, approaching zero at infinite separation.
The inverse-square relationship is why orbital altitude changes gravity far less than intuition suggests — at 400 km, gravity is still about 89 per cent of its surface value.
This calculator takes 3 inputs: First mass, Second mass, Distance between centres. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.