The Collaborative International Dictionary
Libration point \Li*bra"tion point`\ (l[-i]*br[=a]"sh[u^]n point`), n. any one of five points in the plane of a system of two large astronomical bodies orbiting each other, as the Earth-moon system, where the gravitational pull of the two bodies on an object are approximately equal, and in opposite directions. A solid object moving in the same velocity and direction as such a libration point will remain in gravitational equilibrium with the two bodies of the system and not fall toward either body.
Usage examples of "libration point".
Actually, we'll have a few hours before they drift far enough to destroy the effect, but we'll need all that time because we need to fire the engines at full power to force the tidal bulge past the libration point.
Moonbase's regular commsat, hovering at the L-l libration point above the lunar equator, could not 'see' the deep valleys of the mountainous south polar region, so the polar orbiting minisats were necessary.
The monitor screen in the little editing booth showed what Moonbase's astronomical telescope was focused upon: the clutch of spacecraft hovering around the big space station at the L-l libration point some fifty-eight thousand kilometers above the Moon's surface.
Moonbase's regular commsat, hovering at the L-l libration point above the lunar equator, could not'see' the deep valleys of the mountainous south polar region, so the polar orbiting minisats were necessary.