Buried 60-Km Lunar Volcano Backs Earth-Like Magnetic Field on Moon 4.2 Billion Years Ago
Updated
Updated · DISCOVER Magazine · Sep 28
Buried 60-Km Lunar Volcano Backs Earth-Like Magnetic Field on Moon 4.2 Billion Years Ago
3 articles · Updated · DISCOVER Magazine · Sep 28
Summary
Gravity and magnetic data point to a 60-kilometer-wide, 9-kilometer-deep volcanic complex buried beneath the Moon’s Dewar swirl, linking one of the strongest far-side magnetic anomalies to ancient magma.
That rock body likely cooled about 4.2 billion years ago in a magnetic field of at least 11.4 microteslas, giving researchers a way to estimate the Moon’s early field strength.
Dewar’s location makes an impact origin unlikely, so the team argues the magnetization came from a core-driven dynamo—geodynamic forces akin to those that generate Earth’s magnetic field.
The findings strengthen the case that the Moon once sustained an intense magnetic field, while shifting the debate from whether a dynamo existed to how such a small core produced it.