Viking 'Sunstone' Evidence Found On Sixteenth-Century English Wreck
"Ancient Viking mariners didn’t have GPS or even a magnetic compass, but they still managed to beat Christopher Columbus to America by nearly 500 years. While it’s possible to navigate by observing the position of the sun, just how did seafarers in the northern latitudes manage to find their way when the sky was cloudy?
"Icelandic sagas make mention of a "sunstone" that could be used to find the sun even when it was hidden, thereby guiding sailors safely even in dark and stormy hours. Now, new scientific research implies that the sunstone isn’t just a fable.
"Even when the sun is hidden behind clouds or just below the horizon, it's possible to pinpoint its location by detecting the polarization of light."
http://www.ibtimes.com/viking-sunstone-evidence-found-sixteenth-century-english-wreck-1120939