Moon's Missing Magnetism: Solved by an Ancient Impact?
2025-05-29
The moon's surface rocks show signs of a strong magnetic field, yet the moon itself lacks an inherent magnetic field—a decades-old puzzle. MIT scientists propose a new theory: a large impact generated a plasma cloud, temporarily amplifying the moon's weak intrinsic magnetic field, particularly on the far side. The impact's shockwave further 'jittered' electrons in rocks, causing them to record this brief high magnetic field. This explains the highly magnetized rocks on the far side and predicts the possibility of finding shock evidence and high magnetism near the lunar south pole, a testable hypothesis for future missions.