So, I would imagine this question would have been asked here long ago but the suggested questions and Google is really letting me down now. So, as far as I can tell Plutonium is the heaviest naturally occurring element via electron-capture, but I have not found anything to suggest plutonium is formed in supernovae. So, my question is, Is Uranium really the heaviest element formed in a supernova? If so, is that a known fact or is it conjecture from observation? By that, I am asking if there are mathematical models and whatnot or some other method that it is known plutonium cannot form in supernovae. If it is known, then how is it known.
Also, is it possible that the few so-called "super-Chandraskhar" limit supernovae could possibly form heavier elements?