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Vikings did a lot of navigating in their line of work. Those who didn't know how to use the sun to get exactly where they wanted to go would end up razing only sandcastles, pillaging only bird's nests, and setting fire only to their own beards. So when cloudy, foggy, gray days caused these intrepid seamen to tear the horns off their helmets in frustration, they brought in a pinch hitter. The sunstone was a magical rock that the Vikings used to find where the sun was, even on severely overcast days. More »
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Glass: it's so much more than just the clear stuff in your windowpanes that keeps the cold out.  In fact, we've just learned of a glass that is actually stronger than steel, and just about as tough.  More »
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This photo looks like it could have been taken on another planet - miners harvesting dilithium, perhaps. But this cave full of monstrous crystals is located in Mexico, and the crystals themselves are a form of gypsum, one of the most common elements on Earth. What geologic processes caused the crystals to get so freaking big? More »
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