Vikings navigated by invisible light
Ancient Vikings ingeniously navigated vast oceans using 'sunstones' to detect polarized skylight, pinpointing the sun's position even on cloudy days for epic voyages.
Ancient Vikings, master seafarers, likely used a 'sunstone' to navigate even when clouds hid the sun. This tool, possibly Iceland spar, detected polarized skylight, allowing them to pinpoint the sun's position. By rotating the crystal, navigators could find a bright spot indicating the sun's direction with surprising accuracy. This ingenious method was vital for their epic voyages across the North Atlantic to places like Greenland and North America. It shows an early, intuitive understanding of light polarization, a concept not formally grasped until the 19th century, highlighting Viking ingenuity.