Astronomers Discover Unique Metal Scar on White Dwarf Star

The scar, believed to be remnants of a consumed planetary fragment, challenges previous theories and offers new insights into the dynamics of dead planetary systems.

Astronomers using the European Southern Observatory's Very Large Telescope have discovered a unique metal scar on the surface of a white dwarf star, WD 0816-310, marking the first observation of such a feature.
The metal scar is believed to be the remnants of a planetary fragment, possibly as large as or larger than Vesta, the second-largest asteroid in the Solar System, that was consumed by the white dwarf.
The concentration of metals in the scar is attributed to the star's magnetic field, which funneled the planetary material onto one of its magnetic poles, a process not previously observed in white dwarfs.
This discovery provides new insights into the dynamic nature of planetary systems even after the death of their host star and could offer clues about the bulk composition of exoplanets.
The findings challenge previous theories that expected the consumed planetary material to be evenly distributed across the white dwarf's surface, instead revealing a concentrated patch of metals held in place by the star's magnetic field.