L4

Author: Tianjiang Shuo

Website: https://cislunarspace.cn

Definition

One of the five libration points in the Earth-Moon system, located at the vertex of an equilateral triangle with the Earth and Moon as the other two vertices, 60 degrees ahead of the Moon in its orbit, also called the 'leading' triangular libration point. In the circular restricted three-body problem, both L4 and L5 are stable equilibrium points, but solar gravitational perturbation calls the stability of triangular points into severe question.

References

  • Catlin and McLaughlin, 2007