Attractive Tangles

A model of the geodynamics between the reversals of Earth’s magnetic field.
Image courtesy of G.A. Glatzmaier/Los Alamos National Lab (via Wikimedia Commons)

A supercomputer simulation shows magnetic field lines continuously generated and distorted by the Earth's liquid metal core. Partially mimicking this process, a rotating tank of liquid sodium can amplify the field, the first in a two-step process for generating a self-sustaining magnetic.