Fossil magnetic fields could map the Sun’s distant, magnetized future

Astronomers propose that magnetic fields formed early in a star’s life can survive its evolution, linking magnetic activity observed in red giants to the magnetism seen on white dwarfs via the fossil field theory. Using starquakes (asteroseismology) to probe stellar interiors, they suggest these fossil fields could explain magnetism across evolutionary stages and imply that our Sun’s distant future—swelling into a red giant and eventually becoming a white dwarf—might be influenced by magnetic fields extending into its core. This work could reshape understanding of stellar magnetism and lifespan across the cosmos.