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Voyager and Comets
I have a question for the knowledgeable astronomers using this forum.
Voyager 1 and 2 have now reached, and passed through, the edge of the Heliosheath, at a distance of some 100 AU, and are on their way to Outer Space, travelling at an average of approx 3 AU per year. I understand that the Heliosheath is basically the limit of the gravitational effect of the Sun.
Long Term Comets are thought to originate in the Oort Cloud which has 2 components, an inner part and an outer part. Medium term comets form in the inner cloud, whilst long term comets are formed in the outer cloud, which extends to a distance of 50,000 AU from the Sun. (Short term comets come from the Kuiper belt)
If that is so, then for the comets to be periodic, they must be within the Sun's gravitational field. They come and go, and come and go, so gravity must be the cause of this repetitive journey. If they are just one off comets, any number of events may cause the comet to enter our solar system, but it will then leave, never be seen again.
So what will happen to the Voyagers? Will they continue on their journey for ever, or until they become caught up in the gravitational field of another star, or will they eventually return to the Solar system in x thousand years time, having been to the Oort Cloud and back?
On the assumption that they will go on forever, is it possible that there may be other planets, asteroids etc that have been thrown out of a star system elsewhere in the Universe in a manner similar to the slingshot effects that were contrived by NASA to send Voyager off to oblivion? If so, can it be assumed that there may be some wandering planets in Outer Space, with no Solar system of their own?
I realise that NASA used rocket propulsion, aided by the gravity of the planets, to provide the impetus to get the satellite in the correct position to escape, but couldn't this also happen naturally, given the number of stars and planets out there?
If anyone has answers, or even hypotheses, to these question, I would be most interested in hearing them.
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