Supernovae may generate life-giving carbon atoms faster than thought

A supercomputer shows exploding stars boost carbon production from deep inside.


Michigan State University scientists have found that exploding stars create life-giving carbon atoms much faster than they thought. However, that discovery has created another mystery that could upend current theories of element creation and help fuel new science in the areas of astronomy and fusion.

One of the most abundant elements on Earth, carbon, is created in a “triple-alpha” fusion reaction by exploding supernova stars. That term “alpha” describes a helium atom core made up of two protons and two neutrons. When three of those are fused together, you get carbon with a total of six protons, six neutrons and six electrons.

That fusion reaction is pretty inefficient, however, unless there’s something helping it along. Using supercomputer models, the researchers found that excess protons in the innermost reaches of a supernova can accelerate triple-alpha fusion reactions, generating 10 times more carbon atoms than expected.

That might explain the extra carbon in the universe, but it creates another mystery. Scientists previously though those excess protons were responsible for creating certain heavier isotopes of ruthenium and molybdenum found in surprising abundance on Earth. “You don’t make those elements in other places” besides supernovae, said MSU professor and study co-author Luke F. Roberts.

That means those isotopes might be generated in other ways, but the researchers aren’t sure exactly how. “It’s not easy to come up with alternatives,” said co-author Hendrik Schatz. However, even though the research may have “destroy[ed] our favorite theory,” according to Schatz, it should generate some interesting new science. “Progress comes when there’s a contradiction,” said project lead and former director of the National Superconducting Cyclotron Lab, Sam Austin.