Researchers hypothesize that a type of nuclear fission that occurs in a white dwarf leads to explosions similar to those of an atomic bomb on Earth.
Research published in the journal Physical Review Letters details how reactions can produce a star explosion known as a supernova. Researchers believe these stellar explosions occur as a result of a series of smaller nuclear explosions.
According to the study, crystalline radioactive elements called “snowflake uranium” can appear in white dwarfs. These snowflakes will likely be made of lead, thorium and even have a distinctive crystal structure with half actinides and half light elements.
In seconds, these snowflakes can grow to the size of a grain of sand in a white dwarf.
Because uranium is radioactive and unstable, a nucleus in its composition decays, projects neutrons, and causes a chain of nuclear fission reactions similar to the explosion of an atomic bomb.
This means that small nuclear bomb explosions are the result of larger nuclear bomb explosions across the universe.
These results contradict previous hypotheses that a La-type supernova is the result of a white dwarf in close contact with its companion star.
“People think a white dwarf has a mate because they can’t explain how that star might explode without a mate,” said Charles Horowitz, professor of physics at Indiana University.
Despite these hypotheses, the authors stress that this is only a hypothesis. They have yet to find evidence that the uranium snowflakes actually caused the explosions.
“I think the next, most important step is to just ask our friends who simulate supernova explosions to determine if these little snowflakes are hot enough to trigger a fusion reaction… or not. It’s not impossible – that’s basically the topic of our article. There is still a lot to do, ”said Matt Caplan, associate professor of physics at Illinois State University (United States).
