![\text{distance} = \sqrt[3]{\frac {G M T^2} {12\pi^2}} \approx 260\,000 \text{ AU}.](../a/9e970b317d8b5638.png){kind=small}
It seems clear in retrospect, but apparently the limiting factor that determines the size of the outer solar system is tidal effects due to the Milky Way. It turns out we can calculate the upper limit of the size of the solar system (that is, the distance to the L1 point of the sun and the Milky Way) knowing only the mass of the sun and the galactic year:
An interesting article on the oldest known star:
Follow RSS/Atom feed for updates.