DESI Detects Planetary Debris Around White Dwarf Stars

The Dark Energy Spectroscopic Instrument (DESI), built to map the universe’s expansion, was used as a side project to study twelve white dwarf stars. By analysing their spectra, an international team identified chemical fingerprints of destroyed planetary bodies—elements such as oxygen, magnesium, silicon, calcium and iron, and in two cases signs of water‑rich material. The research, led by Paula Izquierdo of the University of Warwick and involving astrophysicist Detlev Koester of Kiel, shows that white dwarfs preserve the chemistry of disintegrated exoplanets, offering a rare glimpse into the composition of rocky worlds beyond the solar system. Results were published in the Monthly Notices of the Royal Astronomical Society.