On the trail of Vikings with polarized skylight: experimental study of the atmospheric optical prerequisites allowing polarimetric navigation by Viking seafarers
(2011) In Philosophical Transactions of the Royal Society B: Biological Sciences 366(1565). p.772-782- Abstract
- Between AD 900 and AD 1200 Vikings, being able to navigate skillfully across the open sea, were the dominant seafarers of the North Atlantic. When the Sun was shining, geographical north could be determined with a special sundial. However, how the Vikings could have navigated in cloudy or foggy situations, when the Sun's disc was unusable, is still not fully known. A hypothesis was formulated in 1967, which suggested that under foggy or cloudy conditions, Vikings might have been able to determine the azimuth direction of the Sun with the help of skylight polarization, just like some insects. This hypothesis has been widely accepted and is regularly cited by researchers, even though an experimental basis, so far, has not been forthcoming.... (More)
- Between AD 900 and AD 1200 Vikings, being able to navigate skillfully across the open sea, were the dominant seafarers of the North Atlantic. When the Sun was shining, geographical north could be determined with a special sundial. However, how the Vikings could have navigated in cloudy or foggy situations, when the Sun's disc was unusable, is still not fully known. A hypothesis was formulated in 1967, which suggested that under foggy or cloudy conditions, Vikings might have been able to determine the azimuth direction of the Sun with the help of skylight polarization, just like some insects. This hypothesis has been widely accepted and is regularly cited by researchers, even though an experimental basis, so far, has not been forthcoming. According to this theory, the Vikings could have determined the direction of the skylight polarization with the help of an enigmatic birefringent crystal, functioning as a linearly polarizing filter. Such a crystal is referred to as 'sunstone' in one of the Viking's sagas, but its exact nature is unknown. Although accepted by many, the hypothesis of polarimetric navigation by Vikings also has numerous sceptics. In this paper, we summarize the results of our own celestial polarization measurements and psychophysical laboratory experiments, in which we studied the atmospheric optical prerequisites of possible sky-polarimetric navigation in Tunisia, Finland, Hungary and the high Arctic. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1925736
- author
- Horvath, Gabor ; Barta, Andras ; Pomozi, Istvan ; Suhai, Bence ; Hegedues, Ramon ; Åkesson, Susanne LU ; Meyer-Rochow, Benno and Wehner, Ruediger
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Viking navigation, sky polarization, imaging polarimetry, atmospheric, optics
- in
- Philosophical Transactions of the Royal Society B: Biological Sciences
- volume
- 366
- issue
- 1565
- pages
- 772 - 782
- publisher
- Royal Society Publishing
- external identifiers
-
- wos:000286721400020
- scopus:79952347219
- pmid:21282181
- ISSN
- 1471-2970
- DOI
- 10.1098/rstb.2010.0194
- language
- English
- LU publication?
- yes
- id
- 7cd3de4b-7b6c-4c61-999d-f38e1d902c7c (old id 1925736)
- date added to LUP
- 2016-04-01 14:30:52
- date last changed
- 2024-04-24 23:36:14
@article{7cd3de4b-7b6c-4c61-999d-f38e1d902c7c,
abstract = {{Between AD 900 and AD 1200 Vikings, being able to navigate skillfully across the open sea, were the dominant seafarers of the North Atlantic. When the Sun was shining, geographical north could be determined with a special sundial. However, how the Vikings could have navigated in cloudy or foggy situations, when the Sun's disc was unusable, is still not fully known. A hypothesis was formulated in 1967, which suggested that under foggy or cloudy conditions, Vikings might have been able to determine the azimuth direction of the Sun with the help of skylight polarization, just like some insects. This hypothesis has been widely accepted and is regularly cited by researchers, even though an experimental basis, so far, has not been forthcoming. According to this theory, the Vikings could have determined the direction of the skylight polarization with the help of an enigmatic birefringent crystal, functioning as a linearly polarizing filter. Such a crystal is referred to as 'sunstone' in one of the Viking's sagas, but its exact nature is unknown. Although accepted by many, the hypothesis of polarimetric navigation by Vikings also has numerous sceptics. In this paper, we summarize the results of our own celestial polarization measurements and psychophysical laboratory experiments, in which we studied the atmospheric optical prerequisites of possible sky-polarimetric navigation in Tunisia, Finland, Hungary and the high Arctic.}},
author = {{Horvath, Gabor and Barta, Andras and Pomozi, Istvan and Suhai, Bence and Hegedues, Ramon and Åkesson, Susanne and Meyer-Rochow, Benno and Wehner, Ruediger}},
issn = {{1471-2970}},
keywords = {{Viking navigation; sky polarization; imaging polarimetry; atmospheric; optics}},
language = {{eng}},
number = {{1565}},
pages = {{772--782}},
publisher = {{Royal Society Publishing}},
series = {{Philosophical Transactions of the Royal Society B: Biological Sciences}},
title = {{On the trail of Vikings with polarized skylight: experimental study of the atmospheric optical prerequisites allowing polarimetric navigation by Viking seafarers}},
url = {{http://dx.doi.org/10.1098/rstb.2010.0194}},
doi = {{10.1098/rstb.2010.0194}},
volume = {{366}},
year = {{2011}},
}