November 2, 2011 18:10
Experimenters explained theoretically and demonstrated experimentally, as the ancient mariners used to navigate a particular mineral in cloudy weather.
A group of researchers from France, the U.S. and Canada conducted a series of experiments which indicate that the legendary Solar Stone (sunstone) was a Viking Iceland spar — polarizing light crystal double refraction.
By itself, this idea is not new, but the researchers have tried to bring under this assumption the most complete scientific basis.
From ancient sources that the Scandinavians could determine their position at sea, even in those moments when the sky clouds and dragged to the eye it was difficult to identify the position of the sun. Magnetic compass navigators of that era was unknown. Finally, the stars in the summer months, but in high latitudes (near the Arctic Circle) count, for obvious reasons, the Vikings were difficult.
In early 2011, another group of experts conducted extensive theoretical and practical studies, showing that a series of minerals due to its polarizing properties, could play the role of the solar stone, helps Vikings while traveling to America.
Watching the sky through a mineral and turn the sailors tracked ray brightness fluctuations. These fluctuations are due to the fact that the sunlight, even filtered fog and clouds in the sky keeps specific pattern of polarization, which reacts crystal polaroid.
In that work, scientists have proved that the principle of orientation to polarized light in the whole work, although the reliability and accuracy of his — not so great.
Now, as reported by BBC News, the experimenters found that Iceland spar is not just great for the role of the sun stone, but also allows to navigate in space with high precision.
Scientists have found that the intensity of the so-called leveling the ordinary and extraordinary beams that have passed through the crystal, it is possible to know the direction of the sun to an accuracy of a few degrees.
Indirect sign of his innocence study authors called an example, if not the history of the Vikings, in any case, very distant past. On board the Elizabethan ship sank off the island of Alderney (Alderney Elizabethan Wreck) at the end of the XVI century, archaeologists found a piece of Iceland spar. Perhaps he also served for navigation purposes.
(Details of the new work reveals an article in the Proceedings of the Royal Society A.)