text: Jupiter, while larger than all the other planets in our system put together, is still far too small to have ever been a star in its own rights. Furthermore, stars don't just "burn out". Depending on thier mass, they can undergo a number of different evolutions; many will go super-nova, spewing out unimaginable ammounts of heavy atoms and radiation, others will diminish into brown or whites "dwaves", still others will form black holes. \n\nIt might be possible (though incredibly unlikely) for a solar system to "ensnare" passing planetoids, but they would be unlikely to form stable orbits in the time that our solar system has been around.\n\nIt's an interesting idea, and although jupiter could never have been a star, it is proponderously unlikely, but not impossible, that it could have originated outside of our solar system.