Free Astronomy Magazine January-February 2026

38 ASTRO PUBLISHING cal changes.” Spectroscopic data obtained using the High-Resolution Echelle Spectrometer (HIRES) instru- ment on Keck I revealed the white dwarf’s atmosphere is polluted with 13 chemical elements, evidence of a rocky body at least 120 miles wide (200 kilometers) that was torn apart by the star’s gravity. “This is one of the very few times we can see direct evidence of planets being ripped apart and falling onto a dead star,” said Keck Observatory Chief Scien- tist John O’Meara. “We don’t have many of these systems where we see polluted white dwarfs. This par- ticular system has the largest amount of heavy elements seen to date which proves it was an old, rocky planet.” Hydrogen-rich at- mospheres around white dwarfs typically mask such elemental signa- tures, making this detection espe- cially significant. “Something clearly disturbed this system long after the star’s death,” said co-investigator JANUARY-FEBRUARY 2026 A stronomers using data from the W. M. Keck Observatory on Maunakea, in Hawai ‘ i, have identified a rare, ancient plan- etary system still being actively con- sumed by its central white dwarf star, LSPM J0207+3331. Located 145 light-years from Earth, this system hosts the oldest and most heavy metal-rich debris disk ever observed around a hydrogen-rich white dwarf, raising new questions about the long-term stability of planetary sys- tems billions of years after stellar death when fusion has ended in the star. The study, led by Érika Le Bour- dais of the Trottier Institute for Re- search on Exoplanets at Université de Montréal, has been published in The Astrophysical Journal . “This dis- covery challenges our understand- ing of planetary system evolution,” said Le Bourdais. “Ongoing accre- tion at this stage suggests white dwarfs may also retain planetary remnants still undergoing dynami- Aging white dwarf still consuming its planetary system by Keck Observatory Meagan O’Shea T his artist’s illustration shows a 3-billion-year-old white dwarf star accreting material from the rem- nants of its former planetary system. Gravitational instabilities caused a surviving planet to spiral inward and disintegrate under intense tidal forces, forming a debris disk. Spectro- scopic analysis of the white dwarf’s atmosphere revealed the presence of this planetary debris. [NASA/ESA/ Joseph Olmsted (STScI)] John Debes of the Space Telescope Science Institute in Baltimore, Mary- land. “There’s still a reservoir of ma- terial capable of polluting the white dwarf, even after billions of years.” Nearly half of all polluted white dwarfs show signs of accreting heavy elements, indicating their planetary systems have been dy- namically disturbed. In the case of LSPM J0207+3331, a recent pertur- bation— within the last few million years—probably sent a rocky planet