The protective shell of our planet is not what it used to be. Nobody knows why its magnetic strength has nosedived over the past two centuries.
The South Atlantic Anomaly, a soft spot in the field, has blisters over the Atlantic ocean and is problematic for delicate circuits on satellites.
There are concerns that we might be seeing signs of an imminent reconfiguration that would change the direction of the compass points all topsy-turvy.
The researchers behind the new investigation warn us not to be too hasty in assuming that will happen.
The South Atlantic Anomaly is predicted to disappear within the next 300 years based on similarities with the anomalies recreated.
It's not any time soon. We can breathe easily for now.
Our geological history shows that the lines of our planetary magnetic field will eventually point in a different direction.
It's not clear what a reversal would mean for the world. A rain of high-speed charged particles ripped through our atmosphere 42,000 years ago, causing life on Earth to go through a rough period.
It's not clear whether we humans noticed or responded by spending more time indoors.
Even the most rapid of field reversals in the foreseeable future would leave us exposed because of our reliance on electronic technology.
It's important for geologists to know which wiggles, wobbles, and wanderings in the field signify catastrophe and which mean business as usual.
The orientation of the magnetic field causes molten materials to line up before being locked in place. The record of which way the compass pointed throughout the millennia is provided by digging through layers of arrows.
Pottery artifacts from archaeological sites can give a snapshot of the field in the past, capturing its direction in clay before firing.
Researchers from Lund University and Oregon State University reconstructed a detailed timeline of our planet's magnetic shell using samples from around the world.
The South Atlantic soft-spot is not completely out of the ordinary. A similar geological change took place over 1,300 years ago.
Assuming the same basic mechanics are being used, the current patch of weakness will soon regain strength and fade away. We haven't seen the magnetic field bounce back like this in a long time.
There is new evidence suggesting we shouldn't interpret anomalies of diminishing strength as signs of a polar flip.
That's good news in some respects. We don't know what a huge geological process will look like in a human lifetime.
If the worst happens, we'll be prepared for it, since having detailed records like this one helps build a clearer picture.
The research was published in a journal.
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