"Sunstones" aid in Viking navigation

Hungarian researchers report that viking sailor used special crystals they called "sunstones" to aid in navigation. These stones helped polarize sunlight that was obscured by clouds and fog common to sea travel in Arctic climates.

The research was led by Gabor Horvath from Eotvos University in Budapest, Hungary who "spent a month recording polarisation - how rays of light display different properties in different directions - in the Arctic."

Thanks to THL Francesca de Onorati for the link.