🚀 go-pugleaf

In article <11854@dartvax.Dartmouth.EDU> dalex@eleazar.dartmouth.edu (Dave Alexander) writes:
>So if L1, L2, and L3 are loci of unstable equilibrium, how can we expect
>an object to librate or oscillate about any of them?

You can't, and it won't, without help.  An object *precisely* at one of
those points, with *no* perturbations, would stay there, but in the real
world, that doesn't work.

There are trajectories near those points -- so-called "halo orbits" --
which are *almost* stable, requiring only very slight corrections to
maintain.  ISEE-3 was in a halo orbit around the Earth-Sun L1 point for
some years, to study the solar wind "upwind" of Earth.
-- 
Allegedly heard aboard Mir: "A |     Henry Spencer at U of Toronto Zoology
toast to comrade Van Allen!!"  | uunet!attcan!utzoo!henry henry@zoo.toronto.edu