[jessriedel]

> The article is silent on item d.

I believe the mass and orbital parameters necessary to clear an orbit of debris are known pretty well known theoretically, and farout won't satisfy it. This is why astronomers can "be looking for Planet 9/X/10" without searching for debris everywhere. (Likewise, knowing the rough mass is enough to know whether a body has a hydrostatic shape; you don't have to actually resolve it's shape in your telescope.)

Edit: yep: https://en.wikipedia.org/wiki/Clearing_the_neighbourhood#Cri...