Lagrange point

Equilibrium points near two orbiting bodies

In celestial mechanics, the Lagrange points, also called the Lagrangian points or libration points, are points of equilibrium for small-mass objects under the gravitational influence of two massive orbiting bodies. Mathematically, this involves the solution of the restricted three-body problem. Normally, the two massive bodies exert an unbalanced gravitational force at a point, altering the orbit of any other celestial body at that point.

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