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Hold on Tight! Earth's Magnetic Field May Be Preparing to Flip!
News story originally written on May 20, 2003

What if compass needles pointed towards the South Pole instead of the North Pole?

Someday it will happen!

The Earth's magnetic field is very helpful if you are trying to find your way around the planet using a compass. However, the magnetic field has been getting weaker, decreasing by about 5% each century. This might be a sign that a magnetic field reversal is beginning. That's when the North and South magnetic poles flip!

The magnetic field does not change overnight. It takes thousands of years. The field strength decreases and then returns a few thousand years later with the magnetic North and South Poles reversed. Magnetic reversals happen on average every 250,000 years, but it has been 750,000 years since the last reversal.

Magnetic reversals don't appear to have caused any harm to animals and plants in the past. (But we might all get lost if our compasses don't work!)

Last modified May 22, 2003 by Lisa Gardiner.

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