the distance from the centre of a body, such as a planet, at which the tidal forces are stronger than the mutual gravitational attraction between two adjacent orbiting objects
Word origin
C19: named after E. A. Roche (1820–83), French mathematician
Roche limit in American English
(roʊʃ)
the lowest possible altitude at which a natural satellite can form and orbit, withstanding the fragmenting force of the gravitational pull of a planet or other primary celestial body