There is evidence that it did occur on earth some two billion years ago, in a few places with high levels of uranium present. As far as the rest of the Universe, we just don't know.
Nuclear reactor
It happened in the center of the universe, for which it is still expanding on the universe.
It would become an atom of a different element. This can only happen during radioactive decay, nuclear fusion, or nuclear fission.
The Big Bang refers to the event that created the universe. It is not expected to happen again as the universe is already expanding and evolving from that initial event. However, there are theories like the Big Crunch or Big Rip which describe possible future scenarios for the universe.
Fission products are the fragments resulting from the fission of heavy nuclids during nuclear fission process
Nuclear reactor
Fission reactions typically occur in nuclear reactors where heavy atomic nuclei split to release energy. Fusion reactions, on the other hand, occur in stars like the Sun where light atomic nuclei combine to release energy. Both processes play a crucial role in generating energy and elements in the universe.
Disney Universe happened in 360.
Entropia Universe happened in 2003.
Lego Universe happened in 2010.
Fission
It happened in the center of the universe, for which it is still expanding on the universe.
Fission and fussion manly occar in a star or a sun. The reason that a star or a sun is bright is because of the heat that is given off of from fission and fussion.
Well if it DOES happen and a black hole DOES destroy the Universe, then we won't be around to worry about it.
Mega Man Universe happened in 360.
Phantasy Star Universe happened in 2006.
Bust-a-Move Universe happened in 2011.