At the end of their lives, our sun could end up as a crystal – and physicists now have evidence of this theory.
Scientists have predicted that white dwarfs can crystallize in a phase transition that freezes like ice. New research by scientists in the UK, USA and Canada confirms this transition in a survey of nearby white dwarfs. This is particularly interesting for us, because scientists, as we have reported, predict that the fate of our own sun will become a white dwarf.
White dwarfs are small, faint, and incredibly dense stars that are the result of stars like the sun being the fuel for their nuclear fusion. They have masses around the sun but are only about the size of the earth. They consist of a densely packed plasma of atoms and their electrons. According to the rules of quantum mechanics, electrons are forbidden to share precise states so that they exert a pressure that prevents the stars from collapsing.
Although they are plasmas, scientists have long predicted that these crushed atoms would eventually crystallize, starting at the star centers. Crystallization was observed indirectly, but scientists now claim to have directly observed the process. They describe their results in an article published in Nature.
Models suggest that white dwarfs release heat during crystallization to enter the low-energy phase. The heat energy leaves the water when it freezes to ice. This would slow down the star's cooling, an effect that scientists can directly observe.
The team analyzed a catalog of 15,109 white dwarf candidates within 100 parsecs (326 light-years) of our Sun using data from the Gaia satellite. In fact, at certain points along a graphical representation of color and brightness, they found a "clustering" of stars. This is proof that stars go through the phase transition from the plasma to the crystal, the paper said.
Obviously this depends on the modeling and maybe other explanations could better explain the data. But it's exciting – that would mean that many white dwarfs could be older than scientists thought, because crystallization slows down the aging process.
And one day our sun can be a beautiful crystal ball too. And we will be dead.