NOVA - Magnetic Storm

Magma in core produces magnetism (unknown why). There are ppl superheating/pressurizing metals attempting to observe.

Basically, the Earth is a liquid magnet - and liquids are just that .... liquidy. So the poles move around, and sometimes you'll have bursts of positive charge appearing in the negative side, etc. When enough bursts occur, the poles start to change strength and even flip. We can see evidence of this by looking through 3 things: cooling lava, cooling clay, and sailor's comparisons of true north. Sailors compare where the compass north is to an astronomical reading and have recorded it - and through history you can see changes. Cooling is seen because after the element is headed - the substance polarizes to the earth's magnetic pull. By knowing when pots are thrown, we can see the magnitude and direction of earth's magnetism. Similarly we can see lava in stages of it being cooled to note changes. There was even a period of time (long ago) where the polarity swapped in a matter of 6 days - you would SEE the compass needle change... if one existed...

So how does this effect us? Well the polarity generates a magnetic field that protects us from the sun's radiation - it reflects it to the north/south (Aurora Borealis) and back into space. The radiation could cause significant amounts of cancer, the loss of atmosphere, etc - in fact, this is what seemed to happen to Mars. It has no poles, but lava is polarized EXCEPT where two asteroids hit it and remelted the rock. Since that rock is not polarized, then there was no field when those asteroids hit.

So when? The magnitude of the poles have dropped dramatically - fastest it's been since civilization, and the rate is increasing. However, if there IS a swap, it's not expected for thousands of years.

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