Earth’s Magnetic Field Could Take Longer to Flip Than Previously Thought
by Emily Toomey Smithsonian.com
Swirling around the solid inner core of our planet, more than 1,800 miles below the surface, hot liquid iron generates a magnetic field that stretches beyond the atmosphere. This field provides us with everything from compass directions to protection from cosmic rays, so it’s no surprise that scientists were alarmed earlier this year when they noticed that the northern magnetic pole was rapidly drifting towards Siberia. While geophysicists scrambled to release an updated model of Earth’s magnetic field ahead of its five-year schedule, the migrating pole posed an urgent question: Is the Earth’s magnetic field preparing to flip?
The magnetic state of our world is constantly changing, with the magnetic north and south poles wandering by a few degrees every century or so. Occasionally the magnetic field experiences a complete polarity reversal, causing the magnetic north and south poles to switch places, although no one knows exactly what causes this turnabout. (In fact, the north pole of the planet is a magnetic south pole right now, but it is still referred to as “magnetic north” to correspond with our geographic measurements.)