Re: [Phys-L] Ex: Roche limit

["Albert J. Mallinckrodt" <ajm@cpp.edu>]

Tidal forces don’t so much “destroy it” as simply prevent it from forming in the first place.  It’s simple to understand qualitatively as the competition between the self-gravitation of a non-compacted, self-adhering accumulation of dust and the tidal forces across its radial extent.  If the object is held together by more than mere self-gravitation (e.g. the space station!), it’s another story.

John Mallinckrodt
Cal Poly Pomona

> On Jan 27, 2020, at 10:16 AM, Anthony Lapinski <alapinski@pds.org> wrote:
>
> I'm discussing the solar system, planetary rings, Comet Shoemaker-Levy, and
> the Roche limit in my astronomy class. When a natural satellite moves less
> than 2.4 X a planet's radius, tidal forces from the planet destroy it. Does
> anyone know of a good explanation/reference that derives this number? I
> imagine it is a bit complicated for a high school class.
>
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