I just thought about planet's orbit and then came the thought that for a number of planets to have a trajectory that puts in in orbit around the sun inside of plutos radius,
there must be a truck load of planetoids who didn't have just the exact right velocity and trajectory to maintain a close orbit and that may have drifted outside in the past few billion years. I would guess these rogue planetoids would be still in our neighborhood closer to the sun than to other stars. Just a thought. If there was an earth sized planet 70 times farther away than plutos orbit is it likely we would have found it by now or would it be more likely that we would not have?