Leif K. Karlsen:
Secrets of the Viking Navigators
Leif K. Karlsen at the Helm of Borgunknarren.

Image courtesy of One Earth Press .

Leif K. Karlsen at the helm of "Borgunknarren."
Leif K. Karlsen's book.

Secrets of the Viking Navigators by Leif K. Karlsen
Image: One Earth Press.

To buy the book directly from the publisher visit: One Earth Press . You may also download a nifty free poster from their website.

See a movie of the Gokstad Viking replica, "Gaia," sailing in Sandefjord, Norway on YouTube.
In 2003, the late Leif K. Karlsen produced a wonderfully written and thoroughly researched book on Viking Navigation; one which only a professional navigator such as he, with obvious great admiration for the skill of those ancient seafarers, could write. Not only does Karlsen explore the Viking Sunstone theory, he demystifies many aspects of Viking navigation.

Please note: a 2011 peer-reviewed scientific paper published in the Proceedings of the Royal Society, Series A Journal goes into great detail about the optics, see: Ropars,G., et. al."A depolarizer as a possible precise sunstone for Viking navigation by polarized skylight" Full Text Here and do not miss the Society's later follow-up publication of Dr. David Burch's Comment which acknowledges Leif Karlsen's earlier publication, "Secrets of the Viking Navigators".

The first part of the book chronicles a fictional voyage of a Viking captain and his crew from their home in Norway to Iceland and paints the scene for the latter part of the book which goes into rich detail about Viking navigational aides and techniques (including the Zenith stars as they appeared in the year 1000), seamanship, historical records and other lore; substantiating these with his own navigational expertise.

Using his research and his navigational skills, Karlsen seeks to solve the mystery of how the Vikings could have determined the vital position of the hidden sun. In his book he writes: "During the middle of the summer there is too much light in the night sky to see the stars at the high latitudes where the Vikings sailed. The sun was the only dependable celestial body available for reference." He explores hints in the ancient Viking Sagas, as well as Thorkild Ramskou's theory of a mineral answer, by devising and successfully utilizing what he considers to be the most obvious choice: calcite.
Karlsen makes a very strong case for Iceland Spar. His proposed technique is premised on the ready availability of optical quality calcite in an area of Iceland where the Vikings made first landfall and which relies on the mineral's high birefringence. Mr. Karlsen devised a plausible scenario as it might have happened more than 1000 years ago and which he proved to be extremely accurate.

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The Vikings reached their destinations by latitudinal sailing, that is to say they sailed in straight east-west courses. They used a myriad of navigational clues and techniques to hold to this kind of course, such as observation of sea-birds, waves, stars and the sun. Karlsen found that with the help of a calcite sunstone and a "bearing board," very accurate determinations of latitude could be obtained.
Karlsen explains that a particular course was named by its end-points. If a voyage started at Stad, Norway and ended at Torshavn in the Faeroe Islands, then this latitude of approximently 62 degrees was called "Stad-Torshavn". This was a distance of 332 nautical miles at an average speed of 6 knots. Stad, though located in waters which were known to be very often dangerous, was chosen because it was at the correct latitude to reach Torshavn. To reach Iceland from Stad, they first headed North along the Norwegian coast before turning west on a line to Horn, Iceland.

Having been myself to Torshavn I can say it would be a very skilled navigator who could hit that small rock dead-on as it rises up high out of the sea! It is a very beautiful place right out in the middle of what looks like empty ocean. The island is covered with colonies of seabirds nesting on its shear cliffs. Once close enough, on a clear day perhaps the crew could see the islands in the distance and find the birds, but in a fog....
Karlsen devised an ingenious stand for using the sunstone; one which his Viking ancestors probably didn't think of. Because the stone had to be "read" from below and, at the same time held level, he built a stand which employs a mirror so that the viewer need only hold it out in front and look down into the image reflected below the stone. Click for more information.

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Praise for "Secrets of the Viking Navigators"

"Using clues he gleaned from the Icelandic Sagas, his experiences as a professional navigator, and from his voyages on "Borgunknarren," a 60' Viking ship replica, Leif K. Karlsen reveals the secrets of Viking Navigation. Karlsen has done extensive research on the Viking "sunstone" and "horizon board and explains how they work. This is an interesting, valuable, and educational contribution to the understanding of the Vikings' success as navigators and seaman."
Dr. Alf Lunder Knudsen, Editor Emeritus "Western Viking" The Norwegian Voice of America since 1889.

"If 'cutting edge' can be used in relation to Viking navigation, this information is definately it. Leif Karlsen is the world's foremost scholar on the Viking sunstone. His well-researched and intelligent work on Viking navigation examines the sagas and combines that information with the experimental and practical research of just trying it out. It's a comprehensive and accessible study that's also a compelling analysis of the secrets of Viking Navigators, and their unparalleled success as sea-born explorers."
Kristine Leander, Ph.D., Director, Leif Erikson International Foundation

"Most navigators have heard of Viking sunstones, but few realize they were more than a legend. Leif Karlsen has brought them to life. He shows us how they work, now, and a thousand years ago, and what it was that led the Viking navigators to develop this unique tool for finding the direction to the sun, even when the sun is obscured by clouds or fog.
David Burch, Ph.D., Director, Starpath School of Navigation, Seattle, WA.

To buy the book directly from the publisher visit: One Earth Press . You may also download a nifty free poster from their website.

To find more information on navigation, including courses at their school, visit the: Starpath Website

Leif and June on Gyrfalcon.
Photo: June Garrett-Groshong.

Leif and his wife June on Gyrfalcon which Leif had built in his Norwegian homeland.
Leif K. Karlsen passed away in February 2008 at the age of 77.

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