Armagh, Northern Ireland – Astronomers have made a fascinating discovery of a unique star, WD 0816-310, located approximately 63 light years away. This white dwarf star exhibits a dark metallic “scar” on its surface, believed to be the result of a fragment from a doomed planet that ventured too close to its host.
The presence of this concentrated patch of metals on the white dwarf’s surface has captured the attention of experts in the field. Stefano Bagnulo, an astronomer leading the study at the Armagh Observatory and Planetarium, notes that some white dwarves are known to consume parts of their planetary systems.
Contrary to previous assumptions, where ingested planetary fragments would disperse across the star’s surface, this particular discovery shows these materials being held in place by the star’s magnetic field. The metallic patch covers a significant portion of the pole, resembling the size of Antarctica on Earth.
White dwarfs form when a dying star expels its outer layers, leaving behind a dense core. These remnants possess immense gravity, capable of tearing apart any planets or asteroids that come too close. Jay Farihi, a professor of astrophysics, explains that the gravitational forces lead to the fragmentation of planets or asteroids before they are ultimately consumed by the white dwarf.
The metals observed on WD 0816-310’s surface suggest the potential presence of a planetary fragment as large as Vesta, one of the solar system’s sizable asteroids. Scientists have noticed changes in metal detection as the star rotates, signifying a concentration of metals on a specific area rather than an even distribution.
Further observations have revealed that these variations are synchronized with shifts in the white dwarf’s magnetic field, indicating that the metal scar is positioned at one of its magnetic poles. This discovery opens up new possibilities for astronomers, shedding light on the composition of exoplanets through the study of polluted white dwarfs.
Experts emphasize that this scar on WD 0816-310 represents a unique concentration of planetary material, suggesting a significant milestone in astronomical research. The findings of this study have been published in the Astrophysical Journal Letters, showcasing the ongoing exploration and discovery within the realm of astrophysics.