Don’t flip out: Earth’s magnetic poles aren’t about to switch | Science News

MISSION CRITICAL

Support credible science journalism.

Subscribe to Science News today.


News

Don’t flip out: Earth’s magnetic poles aren’t about to switch

Weakening magnetic field is a return to normal, not a sign of doom

By
3:00pm, November 23, 2015
illustration of Earth's magnetic field

MAGNETIC SHIELD  The planet’s magnetic field isn’t on the cusp of a catastrophic flip of the magnetic poles, new lava analysis suggest. A magnetic reversal would weaken Earth’s magnetic field, causing auroras closer to the equator, as seen in this artist’s illustration. 

Earth is not heading toward a doomsday reversal of its magnetic field, new research assures.

The planet’s magnetic field is about 10 percent wimpier today than when physicists began keeping tabs on it in the 1800s. In the geologic past, such weakening preceded geomagnetic reversals —swaps of the north and south magnetic poles. Such reversals temporarily make the planet more vulnerable to charged particles blasted off the sun that can disrupt power grids and disable satellites.

But that’s not what’s happening now, a new study suggests. While weakening, Earth’s magnetic field is still strong by historical standards. Retracing the strength of Earth’s magnetic field over the last 5 million years, geophysicists have discovered that the field has been much weaker in the past than previously thought. That means that the average strength of Earth’s magnetic field over that longer time period is about

Get Science News headlines by e-mail.

More from Science News

From the Nature Index Paid Content