Re: Solar system building

: Erik Max Francis <max@xxxxxxxxxxx>
: My ultimate point is that a case where forces balances is not
: necessarily stable. For a situation to be stable, there has to be
: restorative forces as well -- that is, small perturbations result in
: restoring forces which put the system back into equilibrium.

Very true. The more usual case is, once you are out of the "sweet spot",
the perturbing forces grow rapidly; balancing a pencil on its point is
a common illustration of it. Out of five lagrange points, only two
are stable; the rest blow up real fast for the smallest gnat-sneezed
size of perturbation. And even the last two aren't stable except for
some ranges of mass ratio. Stable orbits are not exactly easy to come
up with, and with close approaches... well.... even harder.


Wayne Throop throopw@xxxxxxxxx http://sheol.org/throopw
.