Lagrange Points

Occurance
A Lagrange Point is something that occurs in a system of multiple gravitational pulls, like that of the Earth and the Moon. These points occur in any two-body gravitational system. This of course means that Lagrange points exist in the Earth-Moon system, as well as in the Sun-Earth system. These points in the system are gravitationally neutral, the force of gravity is the same in all directions such that there is no net force exerted in that part of space.



Implications
There are always five Lagrange Points in any of the systems described above, and they are all designated L1-L5. If something were placed at a Lagrange Point it would remain there indefinitely. In relation to the two bodies in the system, in our case, the Earth and the Moon, an object at a Lagrange point would be in the same relative position at all times.