The course of human history changed 41,000 years ago because of cosmic forces.
And it will happen again
Earth experienced a rare and powerful geomagnetic disturbance known as the Laschamps Excursion. Unlike a full magnetic pole reversal, which happens roughly every few hundred thousand years, this event was short-lived — lasting only a few thousand years — but it was intense.
During this time, Earth’s magnetic field weakened to less than 10% of its normal strength. Instead of acting like a stable bar magnet with two poles, the field fractured into multiple, scattered magnetic poles. The protective bubble around our planet — the magnetosphere — became leaky, chaotic, and unstable.
The consequences were dramatic.
Auroras, normally confined to the poles, could have illuminated skies as far south as the Mediterranean.
Radiation levels on Earth’s surface likely surged, increasing the risk of sunburn, eye damage, genetic mutations, and birth defects.
Faced with this invisible but powerful threat, early humans — both Homo sapiens and Neanderthals — may have adapted their behavior to survive.
Archaeological and anthropological evidence points to a striking rise in:
- Cave dwelling, possibly as protection from higher UV radiation
- Tailored clothing, offering physical defense from exposure
- Use of ochre pigments on the skin — long thought to be symbolic, but possibly serving as a primitive form of natural sunscreen
A new interdisciplinary study published in Science Advances brings together archaeology, geophysics, and climate modeling to explore how this ancient space weather event may have influenced human behavior. The researchers found that these adaptive strategies became increasingly common across Europe — where the magnetic weakening had its greatest impact..
The worst part? Events like this have happened before — and they’ll happen again.
Understanding how early humans responded to these ancient disruptions could offer us a blueprint for resilience in the future.
Read the study:
Mukhopadhyay, Agnit, et al. “Wandering of the Auroral Oval 41,000 Years Ago.” Science Advances, vol. 11, no. 16, 16 Apr 2025.
