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Message started by phoenixshade on 02/02/11 at 15:20:26

Title: Exploring the Weak Stability Boundary
Post by phoenixshade on 02/02/11 at 15:20:26

This simulation follows a body from just after entering the Hill Sphere of a Jovian planet, with barely enough energy to cross the potential ridge at the L2 saddle point. Since this ridge is "higher" than the one at L1, it is almost guaranteed that it will eventually escape via that path.

The object follows a chaotic trajectory for nearly 40 years before finally finding the neck of the bottle. One of the most fascinating aspects of its path is the figure-eight like motion at several points, especially when it approaches L1 during two failed "escape attempts." All of these motions are all "real..." none of them are artifacts of motions in the z-direction, for instance. All motion is confined to the plane of the ecliptic.

This sim was built as a study of the Weak Stability Boundary (, which has application in mission design. I ran it with a step size of 4 seconds. Each frame in the animation below covers 90 days. It is viewed in a rotating frame with the sun held at the 3 o'clock position.

Chaotic Orbit [animated GIF, 2.04 MB] (


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