There have been natural nuclear reactors, but I don’t think any suffered a catastrophic event. https://en.wikipedia.org/wiki/Natural_nuclear_fission_reactor ht

There have been natural nuclear reactors, but I don’t think any suffered a catastrophic event. https://en.wikipedia.org/wiki/Natural_nuclear_fission_reactor https://en.wikipedia.org/wiki/Natural_nuclear_fission_reacto...