The white dwarf that has researchers intrigued is called WD 0816-310, and it is the remnant of a star slightly more massive than our Sun. All that remains of that star now is the white dwarf core, which is about the same size as Earth.
The researchers were able to learn about this metal scar by seeing how metals were distributed across the star’s surface. The metals aren’t evenly spread but are rather concentrated in particular areas. They could tell this by seeing how the strength of the signal coming from the metals changed in strength as the planet rotated.
The changes in detection levels of the metals were also related to changes in the magnetic field of the white dwarf. The results suggest that the metals are clumped around the magnetic pole, which gives a clue to how they got there: The researchers think that the magnetic field acted like a funnel for incoming matter from the planetary chunk, pulling it onto the star’s surface and creating the scar.
“Surprisingly, the material was not evenly mixed over the surface of the star, as predicted by theory. Instead, this scar is a concentrated patch of planetary material, held in place by the same magnetic field that has guided the infalling fragments,” said co-author John Landstreet of Western University, Canada. “Nothing like this has been seen before.”
