Monday, February 26

Scientists Find a White Dwarf Star Turning Into a Diamond

Scientists have made an intriguing discovery in the realm of stars. They have identified a white dwarf star that is currently undergoing a fascinating transformation into a celestial diamond.

This white dwarf star is essentially the remnants of a sun-like star that has depleted most of its fuel and collapsed. When the core of a star predominantly consists of metallic oxygen and carbon, the subsequent cooling process after it becomes a white dwarf can lead to the formation of an enormous diamond. However, this transformation occurs at an exceptionally sluggish pace, estimated to take one quadrillion years. Given that the universe is a mere 13.6 billion years old, it is unlikely that any star has completed this dazzling metamorphosis. (Just to clarify, a quadrillion equals one thousand trillions, and a trillion equals one thousand billions.)

Nonetheless, scientists now believe they have stumbled upon a star in the early stages of this crystallization process. This star, named HD 190412 C, is located approximately 104 light-years away within a quadruple star system called HD 190412. By calculating the star’s temperature, which measures around 11,420 degrees Fahrenheit (6,300 degrees Celsius), researchers have determined that it falls within the range of a crystallizing white dwarf. The existence of other stars in the same system that have not yet collapsed into white dwarfs allowed the researchers to analyze the metallic composition of the white dwarf’s core. Additionally, they estimated the star’s age to be approximately 4.2 billion years.

Accurate knowledge of the star system’s precise distance from Earth is vital for these calculations, as it directly affects the brightness of the dimming white dwarf. The researchers obtained this information by utilizing data from the European Space Agency’s Gaia Mission, which aims to create a three-dimensional map of a billion stars in the Milky Way.

Armed with these insights, the team constructed a model depicting the cooling process of the white dwarf over time, thereby confirming the first known instance of a crystallizing white dwarf with a known age. Given the presence of similar systems to HD 190412, including the star system that hosts the prominent star Sirius, the researchers suggest that other crystallizing white dwarfs may be located nearby in our cosmic neighborhood.

These intriguing findings were published on June 5 in the preprint database arXiv and have since been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society.

Source: LiveScience / Image: University of Warwick/Mark Garlick