Journal Highlights

Tracing Electric Currents That Flow Along Earth’s Magnetic Field

Research Spotlight—

A new study uses satellite data to examine a worldwide system of electric currents in greater detail than ever before.

The fact that planet Earth is essentially a giant magnet is not a great secret: A compass works because either end of its magnetized needle is constantly being drawn toward the North and South poles. Scientists believe that the Earth’s magnetization is caused by a sea of liquid metal flowing past its solid iron core, creating electric currents and, in turn, magnetic fields.

The Earth’s magnetic fields extend to the ionosphere—a layer of plasma and neutral gases about 50–500 kilometers above Earth’s surface—and the magnetosphere, which starts at the outer edges of the ionosphere and stretches many thousands of miles into space. Magnetic fields from Earth and the Sun affect the behavior of charged particles in the magnetosphere....more

-- Sarah Witman, Freelance Writer,