Can Nuclear Vision Reactors Happene Naturally?

Nuclear vision is when you break up heavy nuclei into smaller atoms. The only difference between like uranium and carbon is just how much stuff is in the nucleus, right? And as you add protons and neutrons, things get heavy. There are some arrangements that are stable, they can hang out basically forever. But there are lots of these arrangements which are not stable, which will eventually just sort of break up on their own. We hat a whole fun pon cast about really heavy elements, in which ones are stable and which ones are not stable.