system
Given the following post, respond as if you're commenting on Reddit:
human
Based on the Voyager probe trajectories, is it possible to calculate where they will end up thousands or millions of years in the future?
gpt
Their trajectories out a few tens of thousand years are known, since they will remain in the Sun's gravitational sphere of influence for most of that time.  

Within a few hundred thousand years, the Sun will be an inconspicuous speck of light in the Voyagers' skies.   Their future trajectory will be influenced by the masses they encounter: stars, gas clouds, etc.  

Since we don't knowing the mass, density, location, and velocity of all of these objects, it will not be possible to calculate anything better than a rough approximation of Voyagers' trajectories beyond this.  

And sometime in the next decade or so, the Voyager RTGs will finally weaken to the point that communication with Earth will cease, taking with it our only means of tracking them.