Scientists Watch a Dead Star Destroy a Planet, In Real Time

White dwarfs are the dense, slowly cooling remnants left behind when stars like the Sun exhaust their nuclear fuel. They no longer fuse atoms in their cores, but their gravity remains intense enough to affect their surroundings. Most are thought to settle into quiet retirement, gradually fading from view over billions of years.

But LSPM J0207+3331 has proven far more active than expected. Scientists using the HIRES spectrometer at the W. M. Keck Observatory in Hawaii have discovered that the star’s atmosphere contains an unexpected mix of heavy elements—evidence that it is currently feeding on planetary debris.

Metal Traces In Dead Star

Spectroscopic analysis of LSPM J0207+3331 revealed the presence of 13 different elements, including iron, nickel, silicon, and calcium—all typical components of rocky planets. According to Earth.com, the material is thought to come from a rocky body at least 120 miles wide that was torn apart and drawn into the star’s gravitational pull.

What makes this detection unusual is the white dwarf’s hydrogen-rich atmosphere. In such stars, heavy elements normally sink out of view very quickly. Their presence now suggests ongoing accretion of fresh debris. Patrick Dufour, co-author of the study from the Université de Montréal, described the amount of material as “unusually high” for a white dwarf of this age.

The chemical composition suggests the parent body was highly differentiated, meaning it had a layered structure with a metallic core and rocky crust, possibly similar to Earth, but richer in iron, nickel, and cobalt. These siderophile (iron-loving) elements tend to concentrate in planetary cores, implying that the star has consumed fragments from deep within a small planet.

Aftershock In Orbit

The remains of the disrupted body now form a warm dust ring orbiting the star. This disk emits a distinct infrared glow, first detected in 2019. The new study links this glow to the recent destruction of a rocky world that passed within the white dwarf’s Roche limit, the threshold inside which tidal forces rip apart smaller objects.

Unlike older disks that may be relics of the white dwarf’s formation, this one appears newly formed, suggesting the planetary body was recently knocked out of orbit. John Debes, a co-investigator at the Space Telescope Science Institute, said: “Something clearly disturbed this system long after the star’s death.”

This kind of activity is not expected so long after a star becomes a white dwarf. It implies that the system remained dynamically active for billions of years, with forces at play capable of altering planetary orbits and sending objects spiraling toward the central star.

Distant Worlds Might Have Triggered Rocky Body’s Fall

One possible explanation for the recent disruption is the gravitational influence of distant gas giants: massive, unseen planets that may still orbit the white dwarf. Their pull could be slowly destabilizing the orbits of smaller bodies, nudging them inward over time. As reported in the same source, these surviving giants are the leading suspects in the planet’s recent destruction.

The idea aligns with models of delayed dynamical instability, in which gravitational interactions slowly unravel planetary systems over long timescales. The study’s lead author, Érika Le Bourdais of the University of Montreal, noted that the ongoing activity of LSPM J0207+3331 challenges traditional assumptions about what happens after a star dies.

If such processes are common, they may eventually affect our own solar system. When the Sun becomes a white dwarf in several billion years, long-dormant planets and asteroids could be pushed into new orbits, leading to similar collisions and dust disks.