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Science

Sunstone Unearthed From Sixteenth Century Shipwreck 114

sciencehabit writes "In 1592, a British ship sank near the island of Alderney in the English Channel carrying an odd piece of cargo: a small, angular crystal. Once it was brought back to land, a few European scientists began to suspect the mysterious object might be a calcite crystal, a powerful 'sunstone' referred to in Norse legends which they believe Vikings and other European seafarers used to navigate before the introduction of the magnetic compass. Now, after subjecting the object to a battery of mechanical and chemical tests, the team has determined that the Alderman crystal is indeed a calcite and, therefore, could have been the ship's optical compass. Today, similar calcite crystals are used by astronomers to analyze the atmospheres of exoplanets—perhaps setting the stage for a whole new age of exploration."
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Sunstone Unearthed From Sixteenth Century Shipwreck

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  • by binarylarry ( 1338699 ) on Wednesday March 06, 2013 @09:03PM (#43100437)

    I hope when it was unearthed the finder said something like "By Odin's Beard! Tis the SUNSTONE that was foretold in the prophecy!"

    At least that's what I would have done. 3

    • by robthebloke ( 1308483 ) on Wednesday March 06, 2013 @09:16PM (#43100545)
      ... and yet everyone else would hear that as:
      Blurgh, Blurgh. Blurgh, blurgh... Bubble, bubble, bubble.... shhhhhheeeeeerssshk... Blurgh, blurgh. Blurgh, blurgh.... Bubble bubble bubble
      • by mcgrew ( 92797 ) * on Wednesday March 06, 2013 @09:56PM (#43100819) Homepage Journal

        That sounds like Vogon, anybody got a babelfish?

        This interested the hell out of me, I'd never heard of it before. Wikipedia says it was used to find the sun on a cloudy day, which would indeed be very useful to navigators with no compasses.

        It also said it's Oregon's official gemstone. No sun or magnets in Oregon?

        THIS is why I love slashdot! Who knew? Not me!

        • by Nidi62 ( 1525137 ) on Wednesday March 06, 2013 @10:03PM (#43100869)

          This interested the hell out of me, I'd never heard of it before. Wikipedia says it was used to find the sun on a cloudy day, which would indeed be very useful to navigators with no compasses.

          I find the timing of this story rather interesting, because the History Channel's newest special miniseries Vikings just started up this past Sunday. In it, the main character reveals to his brother a sunstone that a wanderer had given him. He then proceeds to find the sun through the clouds for his brother, who did not believe that the stone would work.

          • by unrtst ( 777550 )

            I find the timing of this story rather interesting, because the History Channel's newest special miniseries Vikings...

            I was about to say the same thing!

            Oddly, it's the second reference from that series that I ran into today. The other is the Shield Maidens. I just hit a part in the book, "The Mongoliad: Book One" that mentions them. I had never heard of them before the series or the book. (yeah, it's not quite as coincidental timing-wise, since the book was released well before the series, but it was a surprising coincidence to me nonetheless)

          • by Anonymous Coward

            Wikipedia says they can find the sun's azimuth even when the sun is below the horizon!

            http://en.wikipedia.org/wiki/Sunstone

            The name derives from sunstones believed to have been used for navigation in the Middle Ages because their optical properties allow the azimuth of the sun to be detected even when the sun is below the horizon, with an accuracy within a degree or so.[1][2]

            Does this mean at night?

            • by Tuidjy ( 321055 )

              It means before sunrise and after sunset, but not too long either way. Refraction by the atmosphere.

              • The way this works is that the atmosphere polarizes the light from the sun, and that can be detected before the sun rises or after it sets. On an overcast day, the polarization can be detected as well, giving a way to determine the azimuth of the sun even when it can't be seen by eye.

                Calcite is birefriigant, meaning that rays of different polarization pass through a single crystal with rhombic cleavage plans in two paths, which you can see. I would assume that two crystals attached by with different orie

            • Twilight.

          • by Rich0 ( 548339 )

            Might be worth noting that the operation of the stone in the show is fairly different from the description on wikipedia. In the show they basically hold it up to the clouds and see the sun through it. In Wikipedia they describe having to adjust the angle the stone is held at to detect circles in the sky and use that to locate the sun. Whether they are equivalent descriptions I cannot say. When they demonstrated the stone on the show I guessed it was calcite and had something to do with the polarization

          • Monarch Butterflies can do the same thing, they navigate by the position of the sun, but can locate it even on a cloudy day.

            Another amazing fact about monarch butterflies, their migratory pattern lasts 3 generations, so no single butterfly knows, or has ever done the whole trip.

        • by rossdee ( 243626 )

          "That sounds like Vogon, anybody got a babelfish?"

          Believe me if it is Vogon (poetry) you don't want to hear the translation.

          Anyway I wonder how long it will be before someone digs one up around here.
          (I live less than 50 miles from Alexandria, MN)

          • by mcgrew ( 92797 ) *

            If you think Vogon is bad, you should hear that one British kid...

            I wonder how long it will be before someone digs one up around here.

            It isn't that they're rare, it's that we found evidence that the stories of this "magic" stone were true.

          • You can buy them all day long on ebay. They suspected these were used for navigation, this is interesting because it is physical evidence to support that.
        • Like you I looked it up on Wikipedia and was confused. The Sunstone [wikipedia.org] article said it was feldspar, not calcite as in the post. Then I dug deeper and the Sunstone (medieval) [wikipedia.org] article says the original sunstone used for navigation was calcite like Iceland spar. I don't know if the feldspar version could be used for navigation or not.

          BTW, we don't need the sunstones (feldspar version) here in Oregon, we just have a supply for those that do.

    • No, you ninny, everyone know you use a Sun stone to evolve [bulbagarden.net] to evolve their pokemon! ;p

    • by Gilmoure ( 18428 )

      So... no thermo luminescence; no little fuzzy things begging for estefee?

    • needs more 'verily'.

  • by the biologist ( 1659443 ) on Wednesday March 06, 2013 @09:04PM (#43100447)
    I hope that by "battery of mechanical and chemical tests", they meant "showed it to a geologist for five minutes". There are a number of minerals which can mimic calcite to the untrained eye, but they're easy for the specialist to distinguish.
    • by Anonymous Coward on Wednesday March 06, 2013 @10:11PM (#43100923)

      No kidding. 1) it has a hardness of 3 on Mohs hardness scale, 2) it fizzes in acid, 3) it has 3 perfect non-90-degree (rhombohedral) mineral cleavages, etc. Five minutes? More like under one minute. Even the photo is enough to tell that's very probably calcite.

      On the other hand, maybe they needed non-destructive tests, which would make it slightly trickier (hence 5 minutes).

      • by Anonymous Coward on Wednesday March 06, 2013 @11:26PM (#43101363)

        Actually, according to the abstract, they were trying to determine what happened to the crystal while it sat on the seafloor. Alteration from 400+ years of contact with seawater (plus sand abrasion) changed the physical and optical properties somewhat.

        • Re: (Score:3, Interesting)

          by Zyrill ( 700263 )
          Actually, a crystal's basic physical and optical properties do not change even when it is eroded: one unit cell of the crystal has all the determining characteristics that a macroscopic sample would have. Given, it takes some training to tell a rough diamond apart from quartz, but that's what mineralogists and material scientists are for. Oh and one more thing: if it was at least a little transparent, the most readily distinguishable characteristic of calcite is that it's birefringent (check: Wikipedia [wikipedia.org] if y
          • by Anonymous Coward on Thursday March 07, 2013 @01:10AM (#43101899)

            As it happens, I'm a geologist. There's a difference between alteration and erosion. What the article refers to is the exchange of calcium and magnesium between the crystal and seawater (ratios of Ca and Mg move towards equilibrium with the ocean chemistry). That kind of substitution does change your unit cell a bit; which will alter the properties slightly. It would still be calcite (which is ridiculously easy to identify, as you say); just not quite the same calcite it was before it was dunked.

            Reading the summary, it sounds like the calcite had been altered to the point where it couldn't be used as a sunstone (cloudy and scratched). The tests were to determine if the crystal would have made a good sunstone prior to being soaked/abraded.

          • the most readily distinguishable characteristic of calcite is that it's birefringent

            That sounds like some particularly complicated sexual practice. I'm not going to spoil things by looking up what it actually means, as it will certainly be much, much duller.

            • by Anonymous Coward

              Plenty of minerals are birefringent, but calcite is notable because it is so strongly birefringent. Make up your own joke :-)

              Anyway, if you think that's impressive, calcite also has 3 perfect cleavages.

              Careful looking that one up.

    • Actually, I'm kind of wondering how something on a shipwreck could be "unearthed"
  • lost knowledge? (Score:5, Interesting)

    by k6mfw ( 1182893 ) on Wednesday March 06, 2013 @09:15PM (#43100537)

    In a discussion I had with a friend the other day about how did Vikings navigate? Mostly poor weather (no star sightings) and very close to magnetic north pole (compass is useless), or they only traveled part of year when weather was not really bad. One story I heard is they used pressure as a means of navigation. Huh? don't ask me, that is what someone else said. But since that was 1000 years ago, that knowledge is lost so all we have is speculation. Interesting to consider What If... they continued further south and settled in sunny Florida?

    In the book "From Vinland To Mars" published in 1970s it said many Scandinavian men were "landless sons" since first born son inherits the land, and there is not much farmable real estate in those areas. So these landless sons don't have much career opportunity except join the Viking Navy and plunder rest of Europe but there was also motivation to go west to find other places to settle.

    • by alen ( 225700 )

      Same reason why people went west in the USA

      The year 1000 was in the middle of another global warming cycle and there were too many people for some parts of the world. So they went out to conquer, rape and pillage other parts of the world.

    • In those times there was simply not enough land to give each son a piece of the family tracts of land, so yeah, venturing out to sea was basically their only option. It is however an astonishing testimony to their persistence and ability to withstand hardships that they landed on another continent. Having to go cross-continent in a modern flying machine isn't exactly my idea of a fun time, even with all my electronic gadgets - I can't imagine what it must be like to be on a wooden ship for a year or more, w
      • Re:lost knowledge? (Score:5, Interesting)

        by able1234au ( 995975 ) on Thursday March 07, 2013 @01:50AM (#43102069)

        I don't think they went from Norway to Newfoundland. Instead they went Norway -> Orkneys -> Iceland -> Greenland -> Newfoundland. So while still an amazing achievement, it was more like one more hop, mostly west, so tracking the sun is useful for that. The vikings from Greenland that sailed down to L'Anse aux Meadows had already been sailing west from Greenland to trade with the natives (the Dorsets?) and just kept going further. L'Anse aux Meadows was a long way from Greenland and the Indians further south would have been tough to fight, given the population of Greenland was small. So you can see why they did not establish large settlements there. If word had gotten all the way back to Norway and the multiple hops were easier then perhaps more would have settled but it didn't look as attractive as it did for the rest of Europe 500 years later.

    • Ok that that answers the Viking's story, how about the Polynesians?
    • Even with the sunstone, I still wonder how it is actually used in navigation.

      The sunstone obviously determines the direction of where the sun is located - which can basically be anywhere, particularly in summer in the arctic when the sun doesn't set. I know how to get my heading using the sun (unless it's too high above me, like around midday in summer as I'm a hair south of the Tropic of Cancer) and a watch - it basically relies on knowing where the sun is at that moment, and knowing the actual time.

      So now

      • I can't find an image for it now, but I have seen a primitive portable sundial disk. I have a modern version as a novelty.

        If you know north, you can find the time and vice versa. Aha you say, how do you know the time? Well in a "primitive" society, people could develop a sense of what time in was. This could be refined by practicing with the sundisk on land.

        In an earlier age, railway engineers were said to be able to guess the time to a few minutes and only checked their watches for the minute.

        If this cryst

      • You can estimate the time without a watch easy to 30 minutes accuracy.
        So knowing where the sun is gives you a good clue to where south is ... or east or west, depending on the time.
        I'm used to look at the sun and point out north to about 5 - 10 degrees accuracy instantly.

        • Oh, idiot mods around again? Already 2 down mods? For what exactly if I may ask?

      • by jbengt ( 874751 )

        So now the vikings may have had a way to tell where the sun was, with rather high accuracy, without knowing the time that information is rather useless. So something is definitely missing there.

        It's easy to tell when noon is from a sundial. And if you know the date and the elevation of the noon sun, you can tell your latitude. And if you know your latitude and the date, you can tell what time and what direction sunrise and sunset are. And if you know a few times, you can use an hourglass or something to

        • Sundials don't exactly work reliably on a boat.They are highly dependent on being in a fixed direction.

          Also these crystals are typically for overcast days, where you can't see the sun.

          • Up is fixed, even on a boat. You can always find noon with a sun dial. By analysis of the shadow cast by a peg (similar to a sundial) you can calculate if you've deviated from a course provided you know what time it is and have a reference position to check against. The vikings would have known what time it was at least once a day.
    • Re:lost knowledge? (Score:5, Informative)

      by Phrogman ( 80473 ) on Thursday March 07, 2013 @02:50AM (#43102267)

      Its worth noting that while we know the Vikings for their raiding and pillaging, they were in fact some of the most successful traders in Europe at the time. They were also very good and competent craftsmen.
      What we get is the Evil Vikings (tm) version as related by the Christian Church, from when they were (gasp) Pagans and not subject to the rule of that church. Once they had been forced at sword-point to convert to Christianity they became more acceptable. Not that old Norse religion was anything to be particularly happy about mind you. My point is that the Vikings sailed their ships around Europe down into the Mediterranean, conquered Russia (the Rus were effectively Norseman), served as the Imperial Bodyguard for the Byzantine Empire etc. They didn't just destroy and pillage - and most of the other peoples in Europe did a lot of the same thing anyways.
      The Sunstone is a neat idea if true though. I would have bet the Norse navigated mostly by the stars myself, and that they tended to stick to being within sight of land most of the time as most people did prior to the invention of modern navigation.

      • by jabuzz ( 182671 )

        Vikings have a reputation for being "evil" because they luted,raped and pillaged large areas of the British Isles. Sure they might have done other smart things, but that does not detract from the fact that they where nasty pieces of work.

        Invoking Godwin's Law the Nazi's had lots of wonderful technological stuff as well. They where however still evil bastards.

        • Re: (Score:2, Funny)

          by Anonymous Coward

          Vikings have a reputation for being "evil" because they luted,raped and pillaged large areas of the British Isles.

          Thanks you for making my day there :) Luting (http://en.wikipedia.org/wiki/Lute) should indeed be considered evil!

        • by Anonymous Coward

          Well, according to letters we have found from the time, the rape part might have been convinient lie. The danes were taller and blonder than the british, and they bathed regularly and braided their hair and beards. They settled part of Brittain in what became known as Danelaw, and was considered a nuisance because they could seduce even married women. They were later subject to a genocide and wiped out in Brittain.

          • Well, according to letters we have found from the time, the rape part might have been convinient lie. The danes were taller and blonder than the british, and they bathed regularly and braided their hair and beards. They settled part of Brittain in what became known as Danelaw, and was considered a nuisance because they could seduce even married women

            So, a bit like American GIs during WW2 in Britain?

      • by k6mfw ( 1182893 )

        Not that old Norse religion was anything to be particularly happy about mind you.

        but then their religion has exciting characters you can use for comic books, i.e. Thor.

      • Remember there is a difference between a Viking and a Viking age Norsemen. The Vikings themselves had a bad reputation for being evil in large part because they were looting and committing massacres at peaceful monasteries such as Lindisfarne. [wikipedia.org]
    • The vikings did not travel regulary so far north that a compass is useless.

    • In a discussion I had with a friend the other day about how did Vikings navigate?

      If you take a straight left from Scandinavia you'll either hit Britain (which you can plunder/settle) or if you're unlucky and miss it, you eventually get to Greenland then America.

      It's really not that complicated.

  • by Aryeh Goretsky ( 129230 ) on Wednesday March 06, 2013 @09:20PM (#43100587) Homepage
    Hello

    When I first saw the headline, I thought it was going to be a fossilized bioluminescent sunstone [wikispaces.com] from H [wikispaces.com]. Beam [wikipedia.org] Piper [gutenberg.org]'s Little [tvtropes.org] Fuzzy [wikipedia.org] series of science fiction stories.

    Still, a fascinating read, albeit not one as exciting as if H. Beam Piper's fictional sunstones had been found to exist in real life.

    Regards,
    Aryeh Goretsky
    • by Anonymous Coward

      Dear Aryeh Goretsky

      It looks like you're writing a letter.

      Would you like help?

      o Get help with writing the letter
      o Just type the letter without help

      [_] Don't show me this tip again

    • My god! They weren't Vikings, they were Space Vikings! [wikipedia.org] That explains everything!

  • by rusty0101 ( 565565 ) on Wednesday March 06, 2013 @09:42PM (#43100737) Homepage Journal

    Since there appears to be at least two markets for calcite crystals, Astronomers, and I would expect the re-enactment community, I wonder if there is a means of creating either the variety needed by astronomers, or people interested in re-enacting voyages of vikings or others.

    I would suspect that creating them would be potentially less difficult than creating man-made diamonds, but I haven't checked.

    • Well, yeah, but it's Calcium Carbonate, and as such it is also useful in Tums(R) and drywall.
    • I've never heard of anyone in the re-enactment community trying to navigate with one... It would be rather dodgy at best.

      But calcite isn't exactly rare, so there's no need to create it.

      • The question about creating it is not about simply generating calcite, or calcium carbonate, but in generating usable sized high quality crystals. Much of the stuff I've encountered in nature that is large enough to hold has crystals that are growing in multiple directions, with none discreetly large enough to be useful for either use. I'm quite certain that there are larger crystals that would be workable, but I'm wondering if the cost to grow high quality crystals might be low enough to make this into a w

        • According to Wikipedia, it's mined. The "stuff you've encountered" is going to be a vanishingly small sample...

  • Iceland Spar (Score:5, Informative)

    by kbahey ( 102895 ) on Wednesday March 06, 2013 @09:47PM (#43100769) Homepage

    I read about this a while ago, and it was fascinating. Appartently, the crystals polarized sunlight, even if it was through clouds and

    Here are some links that may help:

    The stone itself is calcite, Iceland Spar [wikipedia.org] or the more complex Cordierite [wikipedia.org], also known as iolite.

    Here is one account of how it could have been used:

    Viking Sunstone [polarization.com]

    And here is another:
    Viking Compass [nordskip.com]

    • Re:Iceland Spar (Score:5, Interesting)

      by An dochasac ( 591582 ) on Wednesday March 06, 2013 @10:18PM (#43100983)
      I've done a lot of sailing on the Great Lakes and Irish Sea and I can tell you that cold water often brings a kind of dense low fog. There are times when we can see the tops of masts and blue sky above but because the sun is often low at these latitudes, we can't see where the sun is. But sometimes the fog was so bright, I'd wear sun glasses and then I did notice that the zenith blue sky was polarized. What's more, the digital watch we used for sailing was an LCD watch-- which means it polarized display. And the display did darken noticeably when turned at certain angles, so the reflected sky polarization was also discernible. At the time I wondered whether it could be used as a practical form of navigation, but we had a compass. A few years later Loran-C became popular addition to the compass as and then GPS. But when I heard about the theory that an Iceland spar sunstone might have been used for navigation in the high arctic, I'd give it the nod of plausibility. No it isn't as good as a compass, unless you're above 70 degrees magnetic latitude. No it wouldn't work well under conditions of total cloud cover or rain, might not work at all. But I'm sure this kind of low fog is at least as common in the arctic as it is at my latitude and if I were lost without a compass, GPS, Loran-C on a foggy day, you'd better believe I'd break out the sunstone if I had one.
    • by ScentCone ( 795499 ) on Wednesday March 06, 2013 @11:26PM (#43101369)

      also known as iolite

      Which, as a man of world, you must know is the source of iocane powder. And because iocane comes from Australia, and Australia is entirely peopled with criminals, and criminals would try to fool wandering Vikings into thinking they could navigate with an iolite stone, we know we cannot trust this story they've put in front of us.

  • I've read that Bees also use polarized sunlight to navigate.

    • I've read that Bees also use polarized sunlight to navigate.

      This new learning amazes me, Sir Bedevere. Explain again how sheep's bladders may be employed to prevent earthquakes.

  • Aah That's Clever! (Score:4, Interesting)

    by Greyfox ( 87712 ) on Wednesday March 06, 2013 @09:59PM (#43100837) Homepage Journal
    I imagine that was "magic" back in the day. Just a little Viking sorcery! I suppose the reverse of the rule is also true; any sufficiently antiquated "magic" must seem like technology. Imagine the wonder of the first person to notice this. Did they closely guard their secret? Did this knowledge give them an edge over their neighbors?

    By the time you get to 1767 [google.com], we're definitely leaning more toward "technology" (Though I didn't see this particular one mentioned in said document.) The math and devices are pretty well understood and the methods are shared openly. I'm sure I could find earlier documents if I were inclined to dig around a bit. This one actually popped up on a search for... something else I was looking for. Needless to say, I immediately decided I wanted to be a member of the Order of the Commissioners of Longitude. If they let me in I promise I'll sit in the back and be very quiet...

    • by sFurbo ( 1361249 )
      In the words of Agatha Heterodyne:"Any sufficiently analyzed magic is indistinguishable from technology. "
      • All the science can't really make things stop being magic. The "energy" that all the pieces are made of and the "force" that binds them are no less magic simply because we've given them labels and made rules for predicting and manipulating them. Someone who knows the ways of magic is a wizard. It's kind of amusing if you think about it, the quickest to scorn a supposed wizard would be our scientists and engineers but if scientists and engineers aren't our wizards who is?

        The ancients derived their 10 sphere
    • There's some interesting history behind the Board of Longitude. It was formed in 1714 to judge prizes of up to £20,000 for a reliable method of determining longitude at sea (this was the scientific problem of the day, comparable to the modern search for a cure for cancer or theory of everything). In the early days, the board was flooded with crank proposals, and the commissioners' duties consisted of individually writing letters of rejection. When John 'Longitude' Harrison arrived in London in 1730 wi

  • by GameboyRMH ( 1153867 ) <gameboyrmh@@@gmail...com> on Wednesday March 06, 2013 @10:21PM (#43100999) Journal

    Now I can get my Sunkern to evolve!

  • Guard it closely...

    The Mayan apocalypse, the sequester, and the zombie apocalypse all put together, are a walk in the park, compared to a dark wizard getting ahold of the Sunstone, and casting away the light...

  • ...Or is anybody else feeling all "questy"?
  • I personally never knew the Vikings had this optical compass thing going, but I see interesting possible ties to the Polynesians.

    I spent about 20 years in the jewelry industry and I learned that calcite, at one time, was often mistaken for Diamonds. Calcite deposits are what gives Diamond Head in Hawaii it's name. The calcite was mistaken for Diamonds.

    I wonder what the possibilities are that Polynesians used "Sun Stone" compasses to help find their way around the Pacific?
  • Just a few days ago the new TV series "Vikings" started and they happened to feature a sunstone.. http://www.imdb.com/title/tt2306299/ [imdb.com]

    Well timed I'd say!

    In case you missed it I'm sure it can be found at a certain viking torrent site.. ;) [which I don't condone of course]

  • I misread that headline at first as:

    Smartphone Unearthed From Sixteenth Century Shipwreck

  • ought to be examined as an instance of what-not-to-do technology. I'll believe this is a navigation device when I see one on a FLOATING ship.
  • See people (Score:4, Insightful)

    by xyourfacekillerx ( 939258 ) on Thursday March 07, 2013 @11:54AM (#43105687)
    This is the kind of story that brings me to /. Less politics, more nerd stuff

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