An article published in “Nature” shows the evidence that in white dwarfs oxygen and carbon slowly crystallize from their cores. A team of researchers used data collected by ESA’s Gaia space probe that include distance, brightness and color of hundreds of thousands of white dwarfs analyzing over 15,000 candidates within 300 light years away from Earth to collect evidence of the crystallization process. This is the first verification of a prediction dating back to the beginning of the 1960s.