Lagrange point

The Lagrangian points (IPA: /ləˈgrɑːnʒiən/, French pronunciation: [lagʁɑ̃ʒjɑ̃]; also Lagrange point, L-point, or libration point), are the five positions in an orbital configuration where a small object affected only by gravity can theoretically be stationary relative to two larger objects (such as a satellite with respect to the Earth and Moon). The Lagrange points mark positions where the combined gravitational pull of the two large masses provides precisely the centripetal force required to rotate with them. They are analogous to geostationary orbits in that they allow an object to be in a "fixed" position in space rather than an orbit in which its relative position changes continuously.

A more precise but technical definition is that the Lagrangian points are the stationary solutions of the circular restricted three-body problem.[1] For example, given two massive bodies in circular orbits around their common center of mass, there are five positions in space where a third body, of comparatively negligible mass, could be placed which would then maintain its position relative to the two massive bodies. As seen in a rotating reference frame with the same period as the two co-orbiting bodies, the gravitational fields of two massive bodies combined with the centrifugal force are in balance at the Lagrangian points, allowing the third body to be stationary with respect to the first two bodies

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Reference to Gundam
The Japanese anime sagas of the Gundam series make wide use of massive space colonies parked in Lagrangian points. The colonization of the Lagrange points depicted in the many Gundam series draws extensively from Gerard O'Neill's book The High Frontier: Human Colonies in Space. The series Mobile Suit Gundam, Gundam Wing and Gundam SEED in particular are set around conflicts between Earth and forces acting on behalf of its space colonies.