A planetesimal orbiting within the debris disc around a white dwarf star

Science. 2019 Apr 5;364(6435):66-69. doi: 10.1126/science.aat5330.

Abstract

Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, visible through emission lines. We report a stable 123.4-minute periodic variation in the strength and shape of the Ca ii emission line profiles originating from the debris disc around the white dwarf SDSS J122859.93+104032.9. We interpret this short-period signal as the signature of a solid-body planetesimal held together by its internal strength.

Publication types

  • Research Support, Non-U.S. Gov't