Power Lines In Danger

Power Lines In Danger

. When a coronal mass ejection hits the Earth, electrons in the Earth’s magnetosphere cascade into the polar regions, creating a current that flows along the auroral oval at an altitude of about 100 thousand meters. The magnetic field from this current induces a voltage potential on the surface of the Earth of up to 6 volts per kilometer. A strong pulse of direct current enters long conductors like power lines through their ground connection. This can throw circuit breakers, destroy transformers, and shut down power grid systems, sometimes turning off the lights in entire cities.

Copyright 2010, Professor Kenneth R. Lang, Tufts University