Hardening of inner core may have saved Earth’s magnetic field
Earth’s magnetic field was saved from collapse about 565 million years ago when the planet’s inner core hardened, energizing the field into its current phase, according to a study published online in Nature Geoscience. The finding may also help researchers determine how old the inner core is. The planet’s iron-nickel core is made up of two layers: a solid inner core and a molten outer core. The interplay of the two layers drives the geodynamo, the circulation of iron-rich fluid that powers the magnetic field. That field, surrounding the planet, protects Earth from being battered by the solar wind, a constant flow of charged particles ejected by the sun. click on title above to open article
