Burns, J.A., R.A. Kolvoord and D.P. Hamilton 1989. An assessment of potential hazards to the Cassini spacecraft from debris along satellite orbits. In Cassini Mission Proposal Information Package (JPL PD 699-11) 13, 6-1 to 6-23.

The Cassini spacecraft, which is to orbit Saturn for almost four years during the early part of the next century, is designed to be captured when its engines fire deep within the planet's magnetosphere. Many of the spacecraft's subsequent traverses through the planet's equatorial plane will occur close to satellite orbit paths in order to permit various high-resolution observations of the satellites. In addition, early in the mission the spacecraft will fly along a low inclination path passing over many satellite orbits. Questions have arisen over the years as to whether the regions near satellites are likely to be unusually safe (the simple argument going that the satellites themselves have swept such regions clear) or abnormally hazardous (the point being that, at least for an isolated three-body system, orbits in this locale are the only ones that can possible be stable).

We provide here a preliminary discussion of the likely risk to be faced by a spacecraft passing near the satellite orbits. We start by summarizing the evidence for material in orbit near the satellites; this includes direct observations of co-orbiting moons and dust as well as indirect clues for debris clouds as inferred from charged particle absorption signatures. Following this precis, we consider two different approaches to the problem. First, we recall theoretical results form the classical circular restricted three-body problem as to the circumstances under which orbits are stable versus when they are chaotic; we then illustrate these orbital classes by a numerical simulation that is generalized by showing how it scales for the relevant Saturnian satellites. Second, using arguments coming from theoretical studies of magnetospheric absorption by rings and satellites, we are able to place some very weak constraints on the nature of the material that is thought to be responsible for the observed depletion of charged particles.
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