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On 2025-04-19 05:48:02 +0000, Primum Sapienti said:I'm in the middle of Steven LeBlanc's "Constant
https://phys.org/news/2025-04-earth-magnetic-pole-shift-sunscreen.htmlPresence or absence of aurora borealis does not significantly affect
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The team found that the North Pole wandered
over Europe when the magnetic field's poles
started to flip positions, a natural process
that has happened around 180 times over
Earth's geological history. While the
magnetic reversal didn't complete at the
time, the magnetic field weakened to cause
aurora to occur over most of the globe, and
allowed more harmful UV light to come in from
space.
UV radiation from space. Most UV comes from Sun. Auroras themselves
produce some ultraviolet but much less that Sun. Air under auroras
stops most of UVB and all of UVC, which are more harmful than UVA and
visible light.
Around the same time, Homo sapiens appear toAnother possibility is that Europe received enough immigrants from more
have started making tailored clothing and
using ochre, a mineral that has sun-protective
properties when applied to the skin, with
greater frequency. These behaviors could have
contributed to their spread throughout Europe
and Asia at a time when the Neanderthal
population was declining.
densely populated areas to compensate the greater mortality, be it caused
by auroras or coldness or something else.
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