Aurora, Amazing Northern Lights

In traditional and popular culture
In Bulfinch's Mythology from 1855 by Thomas Bulfinch there is the claim that in Norse mythology:
The Valkyrior are warlike virgins, mounted upon horses and armed with helmets and spears. /.../ When they ride forth on their errand, their armour sheds a strange flickering light, which flashes up over the northern skies, making what men call the "aurora borealis", or "Northern Lights".
While a striking notion, there is not a vast body of evidence in the Old Norse literature supporting this assertion. Although auroral activity is common over Scandinavia and Iceland today, it is possible that the Magnetic North Pole was considerably further away from this region during the centuries before the documentation of Norse mythology, thus explaining the lack of references.