The Roche limit is the distance within which a celestial body held together only by its own gravity will disintegrate due to a second celestial body's tidal forces exceeding the first body's gravitational self-attraction. Inside the Roche limit, orbiting material will tend to disperse and form rings, while outside the limit, material will tend to coalesce. The term is named after Édouard Roche, the French astronomer who first discovered this theoretical limit in 1848.
The Roche limit should not be confused with the concept of the Roche lobe which is also named after Édouard Roche and which describes the limits at which an object which is in orbit around two other objects will be captured by one or the other. ...read more