What is the truth in the legend of the sun stone?

The new study helps clarify the belief in Viking legends about sun stones that can be determined to direct the sun even on a gloomy day.

According to Viking legend, pirates are always able to find the right path, no matter how bad the weather is by using brilliant sun stones. It helps them correctly determine the position of the sun, even when clouded, even when the sun has sunk into the horizon.

Scientists have long conducted many debates about the feasibility of that method. And recently, new research done on crystals discovered from a wrecked ship in the 16th century shows that this stone really exists and can absolutely help Vikings floating on the sea from Na. Uy went to North America without any errors.

According to Viking legends, solar rocks help pirates find the right direction.

More than a thousand years ago, Viking pirates sailed around Europe and the North Atlantic on many long boats, raiding looting, invading the majority of the rich lands in Europe, and then defining Reside in occupied lands. Their search is based on the sun, stars, wind direction and wave direction.

However, these ambitious trips are sometimes difficult to implement because of the dense fog, the cloudy sky, making it difficult to observe the sun and stars.

According to a medieval Icelandic novel depicting a sailor named Sigurd, the mysterious sun stone appears like a "savior" when he is feeling frustrated by bad weather. By raising that stone, Sigurd could see the sun's position and keep the ship in that direction.

In 1967, Thorkild Ramskou, a Danish archaeologist, argued that Vikings' solar stones were Iceland's spar mineral crystals (transparent, colorless calcite) quite popular in the region.

Light passing through calcite leads to double refraction . Accordingly, they separate incoming light rays into two parts according to different paths. Electromagnetic waves oscillate in directions that are perpendicular to the direction of travel. However, when sunlight passes through the Earth's atmosphere, it radiates and vibrates in a specific direction.

The Vikings may have identified based on calcite crystal stones by sweeping them through the sky and finding the position of the sun when the crystals light up. After that, they repeated the procedure to determine whether the sun was no longer visible.

Writing in the Proceedings of the Royal Society, the team led by Ropars Guy from the University of Rennes, Brittany described the experiment on Iceland's spar mineral crystal fragments found in a wrecked military ship. belongs to the reign of Queen Elizabeth First. The ship was discovered in the 1970s off Alderney in the Channel Islands.

They covered a light shield with holes in the center on the crystal. When they looked through the hole, they found the crystal emitted two separate bright parts. When rotating the crystal, one part becomes brighter while the other is dark and vice versa.

Subsequent tests showed that they could find the sun's position by rotating the crystals in the directions until a suitable shadow was found.

'So, when there is no compass in Europe, the sun stone can help Vikings to ship from Norway to the US , ' Guy said. ' The use of calcite crystals is still important even today,' he added.