I want to emphasize that this notion of looking for old ET hardware is more whimsical than serious. Everybody should have at least one nut theory (to keep from being too serious) and this one is mine.

Where would be a good place to park a starship decelleration stage? Answer: The Saturn system. Why? We are assuming that the starship is commanded by a machine intelligence that is essentially immortal. It achieves immortality through self repair. We have a self repair process in our own bodies that is driven by our DNA and cellular biochemsity. However our process of self repair was given to us by 3.5 billion years of evolution and is not yet a technology (we do not control it or even fully understand it). However, the theorized starship and machine intelligence is entirely the consequence of a technology and it understands how it works down to the lowest level. This machine intelligence and its interstellar vehicle would have entered the Solar System after being in interstellar space for centuries. It would be fuel depleted, beat to pieces from collisions with interstellar grains and have most of its electronics fried by cosmic radiation damage. Upon entering our star system, the first thing it would want to do is repair itself. It would need to find a wide variety of raw materials that was readily accessible. Also this vehicle would avoid a world with serious trapped radiation (like the over 1000 Rad radiation belts around Jupiter). One thing this vehicle would probably need lots of is water. The water would be used for extracting deuterium or as a working fluid for an anti-matter propulsion system. The rings of Saturn are mostly water. Upon approaching the Solar System, an interstellar vehicle would examine all of the major planets. Those bright rings of Saturn are like a flashing neon sign saying "Do your repairs here!".

I will be watching Cassini's results from Saturn with great interest.

Gary