Our world is full of chemicals that shouldn’t exist. Lighter elements, like carbon and oxygen and helium, exist because of intense fusion energies crushing protons together inside stars. But elements from cobalt to nickel to copper, up through iodine and xenon, and including uranium and plutonium, are just too heavy to be produced by stellar fusion.
Even the core of the biggest, brightest sun isn’t hot and pressurized enough to make anything heavier than iron.
And yet, those chemicals are abundant in the universe. Something is making them. [Elementary, My Dear: 8 Elements You Never Heard Of]
The classic story was that supernovae — the explosions that tear some stars apart at the end of their lives — are the culprit. Those explosions should briefly reach energies intense enough to create the heavier elements. The dominant theory for how this happens is turbulence. As the supernova tosses material into the universe, the theory goes, ripples of turbulence pass through its winds, briefly compressing outflung stellar material with enough force to slam even fusion-resistant iron atoms into other atoms and form heavier elements.