Researchers say this crystal found at the Alderney shipwreck near the Channel Islands could prove fabled Viking sunstones really did exist.
We all enjoy a tall tale. Cultures with seafaring traditions are especially ripe in what seem like the tallest sea monster tales of all: hydra, kraken, sirens, scylla, leviathans, assorted serpents and mermaids. Usually the stories are never confirmed and usually baseless.
Then again, some of the tales are based on something, or so we are learning as marine scientists plumb the depths and discover some pretty weird creatures. The bottom line: There really are bizarre, unexpected, totally startling monsters found in the seas. And the very worst of these is the most unexpected.
Sea monsters are truly global. This one from Japan serves as the villain for the classic maiden in distress, who awaits rescue by her hero. The poor monsters are almost always cast as the bad guys. And so they usually end hacked to pieces; fish food.
But is there any truth behind these sea serpent tales?
Credit: NOAA/ Bloodydecks.com
Improbable, But True
Maybe it's the oarfish. It looks too monstrous to be true. It can grow many meters long, has strikingly bright silver scales, scarlet fins and some ornate headgear that more than explains why some call it a roosterfish. If only it were a reptile, it'd be a true sea serpent.
Alas. It is a fish. A very weird and beautiful fish, but still a fish.
Largest Serpent of All
There are also other, newfound "sea serpents" our sea-going ancestors never imagined. This one was spotted by a satellite coiling off the south coast of Japan's Hokkaido island.
What do we know about it? 1) It's arguably one of the largest organisms on Earth, 2) It swallows ships, engulfs islands and generally does what it wants, and 3) We're darned lucky it's made of plankton.
Research into such massive blooms and the individual plankton cells that comprise them has revealed surprising cooperation among the microorganisms. They appear to operate like more than just floating individual cells. They live and die for the greater good, it seems. So they may be, in fact, a gigantic watery superorganism.
Now that's a cool monster for you: You can swim in it and never know you've been in the belly of a beast.
The Hokey Hybrids
Mermaids and mermen have always been the stuff of fantasy. Where did the fantasies come from? There are some standard answers to this question, which have always seemed rather inadequate. For instance ... (next slide, if you please) ...
Credit: Getty Images
The manatee has often been called the source of mermaid myths. It's a mammal, so it breathes air. But who would ever mistake a manatee for a sleek and beautiful mermaid?
Could it be love-starved sailors with poor eyesight? There was no shortage of these fellows in the days before optometrists.
Credit: beats me
Another possibility is that merfolk were inspired by fish with roughly human-looking faces, like this fellow. Some fish can look humanoid. That would be enough to get superstitious sailors started.
The Kraken Strikes
How about giant, ship-destroying squid and octopi? These monsters were old hat even to the easily freaked-out. Most folks figured they were historical exaggerations.
That's until some very large and unusual squids started washing up or being hauled in by marine biologists in recent years. Colossal squid are meters long, pretty amazing beasts. Still, they have never been known to lift ships out of the water.
And since were on the topic of squids ...
Spider + Bat + Squid = Sea Monster
Do you remember when this one hit the headlines? It's not so gigantic, at four meters long, but it was observed 3,380 meters down in the Pacific Ocean near Oahu. It's pretty big to have gone unseen before its May 2001 discovery.
So what else is out there? It's pretty clear marine biologists have only just begun discovering what lives in the deep sea. The more time they spend searching, the more they will find. But none would dispute that the nastiest sea monster to ever rise out of the sea is ... (drum roll please) ...
Deadliest Sea Monster Ever
You might have guessed it: Human garbage. Yep. It's the ugliest, most alien-looking, fatal and pervasive monster in the seas. Garbage patches have been getting a lot of attention lately. These are areas on the seas where currents and winds tend to concentrate floating garbage.
Ancient lore has suggested that the Vikings used special crystals to find their way under less-than-sunny skies. Though none of these so-called "sunstones" have ever been found at Viking archaeological sites, a crystal uncovered in a British shipwreck could help prove they did indeed exist.
The crystal was found amongst the wreckage of the Alderney, an Elizabethan warship that sank near the Channel Islands in 1592. The stone was discovered less than 3 feet (1 meter) from a pair of navigation dividers, suggesting it may have been kept with the ship's other navigational tools, according to the research team headed by scientists at the University of Rennes in France.
A chemical analysis confirmed that the stone was Icelandic Spar, or calcite crystal, believed to be the Vikings' mineral of choice for their fabled sunstones, mentioned in the 13th-century Viking saga of Saint Olaf.
Today, the Alderney crystal would be useless for navigation, because it has been abraded by sand and clouded by magnesium salts. But in better days, such a stone would have bent light in a helpful way for seafarers. (Strange & Shining: Gallery of Mysterious Night Lights)
Because of the rhombohedral shape of calcite crystals, "they refract or polarize light in such a way to create a double image," Mike Harrison, coordinator of the Alderney Maritime Trust, told LiveScience. This means that if you were to look at someone's face through a clear chunk of Icelandic spar, you would see two faces. But if the crystal is held in just the right position, the double image becomes a single image and you know the crystal is pointing east-west, Harrison said.
These refractive powers remain even in low light when it's foggy or cloudy or when twilight has come. In a previous study, the researchers proved they could use Icelandic spar to orient themselves within a few degrees of the sun, even after the sun had dipped below the horizon.
European seafarers had not fully figured out magnetic compasses for navigation until the end of 16th century. The researchers say the crystal might have been used on board the Elizabethan ship to help correct for errors with a magnetic compass.
"In particular, at twilight when the sun is no longer observable being below the horizon, and the stars still not observable, this optical device could provide the mariners with an absolute reference in such situation," the researchers wrote online this week in the journal Proceedings of the Royal Society A.
No such crystals have been found yet at Viking sites. The team notes that archaeologists are unlikely to find complete crystals as part of a group of grave goods, since the Vikings often cremated their dead.
But recent excavations turned up the first calcite fragment at a Viking settlement, "proving some people in the Viking Age were employing Iceland spar crystals," the researchers wrote.
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