>That must mean the Sun also has its fair share of that Uranium?

That's a good question. I would assume the sun captured a whole pile of uranium around the time the earth was forming. And it likely sunk to the core. The question is what happened then. The core area is dense enough to fuse hydrogen into helium, without any calculation I'd guess a lot of this is now in much smaller elements as there are a lot of neutrons to break it apart.