Scientists Discover Nuclear Fission Amongst the Stars

Scientists Discover Nuclear Fission Amongst the Stars

For the first time, scientists have discovered nuclear fission occurring amongst the stars, supporting the idea that neutron stars create "superheavy" elements when they collide, which then break down via nuclear fission to birth rare elements. Space.com reports:
Nuclear fission is basically the opposite of nuclear fusion. While nuclear fusion refers to the smashing of lighter elements to create heavier elements, nuclear fission is a process that sees energy released when heavy elements split apart to create lighter elements. Nuclear fission is pretty well known, too. It's actually the basis of energy-generating nuclear power plants here on Earth -- however, it had not been seen occurring amongst the stars before now.

The team of researchers led by North Carolina State University scientist Ian Roederer searched data concerning a wide range of elements in stars to discover the first evidence that nuclear fission could therefore be acting when neutron stars merge. These findings could help solve the mystery of where the universe's heavy elements come from. Scientists know that nuclear fusion is not just the primary source of energy for stars, but also the force that forges a variety of elements, the "heaviest" being iron.

The evidence of nuclear fission discovered by [Matthew Mumpower, research co-author and a scientist at Los Alamos National Laboratory] and the team comes in the form of a correlation between "light precision metals," like silver, and "rare earth nuclei," like europium, showing in some stars. When one of these groups of elements goes up, the corresponding elements in the other group also increases, the scientists saw. The team's research also indicates that elements with atomic masses -- counts of protons and neutrons in an atomic nucleus -- greater than 260 may exist around neutron star smashes, even if this existence is brief. This is much heavier than many of the elements at the "heavy end" of the periodic table.
"The only plausible way this can arise among different stars is if there is a consistent process operating during the formation of the heavy elements," Mumpower said. "This is incredibly profound and is the first evidence of fission operating in the cosmos, confirming a theory we proposed several years ago."

"As we've acquired more observations, the cosmos is saying, 'hey, there's a signature here, and it can only come from fission.'"

The research was published in the journal Science.