The Vikings' Ancient Sun Compass Worked After Sunset
Mar 29, 2014 13:28
The Vikings were great seafarers, and their sun compass was so advanced it even worked after dark. The trick behind it? Magic! Clever engineering and crystals.
According to researchers who examined the Uunartoq disc - a fragment of a Viking sun compass discovered in a medieval convent in Greenland 70 years ago, the 2.8 inch disc was assumed to be part of a compass that used a missing central piece to cast a shadow using cardinal direction.
The Hungarian team posits that the Vikings used a pair of sunstones to help locate the position of the hidden sun. They used a specially designed shadow stick placed on the disc to approximate where an actual shadow would fall if the sun was visible. The outer edge of the shadow would be used for navigation.
The researchers were able to locate true north within a 4 degree margin of error using the twilight compass. They estimate that the method works for as long as 50 minutes after sunset too, making the ancient compass pretty damn useful in both light and near darkness.
The crystals that they used are made of a type of calcite known as Iceland spar, which is a birefringent mineral that creates a unique pattern when exposed to the sun's UV rays.
How does going home to a clean and cozy house make you feel? After a long day and all the stress at work, looking forward to an orderly house with your warm couch while sipping wine or coffee, and eating your favorite food definitely sounds and feels like heaven. Read more
Success in recovering VAT can be achieved with accurate knowledge and practice. The process is complex and necessitates major investments in resources. Due to improper handling of the recovery process, many companies miss out on major savings. It’s essential to understand the areas, conditions and possible methods for recovery because VAT rules change constantly. Read more
Finally, a smartphone microscope that produces crisp, high quality images. Just beyond what the eyes can see - there is an amazing microscopic world, waiting to be discovered. But not every phone magnifier is awesome. Many attempts to magnify with a single lens have created less than satisfactory images. Read more