Simon Kane

The dying Sun may tear the outer solar system apart far sooner than anyone expected. New research in The Astrophysical Journal Letters suggests that once the Sun sheds its outer layers and collapses into a white dwarf, Jupiter, Saturn, Uranus, and Neptune could be thrown into chaos in roughly a billion years—not the nearly eternal stretch of a quintillion years previously imagined. Earth will almost certainly be long gone by then, but the gas giants may not survive either. Traditional models assumed the outer planets would quietly endure for eons until a random passing star finally disturbed them. Researchers Konstantin Batygin and Jim Fuller of Caltech, along with Fred Adams of the University of Michigan, found a more violent possibility: if the Sun loses mass in discrete bursts rather than a smooth wind, the planetary orbits can be destabilized relatively quickly. “Everything changes when the envelope departs in pieces,” the authors wrote. In simulations of 672 burst-driven scenarios, up to 96% of the systems became unstable within 3 billion years after the Sun became a white dwarf. About 40% suffered disruption or violent scattering even earlier, before mass loss was finished. Some planets were ejected entirely; in others, Uranus and Neptune swapped places. Gentler bursts sometimes locked planets into stable resonances that held for billions of years, but the overall picture is clear: the Sun’s death may not be a slow fade. It could be a comparatively rapid, chaotic upheaval that ends the orderly architecture of the outer solar system far sooner than once thought.