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The island France and Spain take turns looking after
Pheasant Island sits in the Bidasoa River between France and Spain, and belongs jointly to both countries. Instead of splitting the tiny island, naval authorities from each side take turns overseeing it. Spain takes its turn from February through July; France takes over from August through January. The island stays where it is, the responsibility, not the land, changes hands.
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The sand dunes that sing
At certain dunes, grains sliding down a slope can produce a deep, booming hum, one you can hear and feel. A sand avalanche can turn an apparently silent landscape into a resonating instrument. It takes the right conditions: grains that are smooth and fairly uniform, along with suitable moisture. When those conditions come together, moving sand can make a low, eerie note.
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The Apollo software that was woven into wire
Some of the software that took astronauts to the Moon was physically sewn into Apollo’s computer. Its fixed memory used wires threaded through magnetic cores: a sense wire passing through a core represented 1; bypassing it represented 0. Software engineers wrote the program, and workers encoded it in wire. The stored instructions joined mathematics with handcraft, computer code made tangible.
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A deep-sea snail with iron in its scales
Some scaly-foot snails near deep-sea hot vents have overlapping foot scales infused with iron sulfide. They secrete sulfur compounds into the scales; iron from vent water diffuses in and reacts, forming tiny mineral crystals. The result differs by location: black snails from one vent field have iron-infused scales, while white ones from another lack this mineralisation. They are the same species, with different mineral finishes.
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A jug that makes you solve a puzzle to drink
How do you drink from a jug with holes around its neck? Puzzle jugs were made for tavern drinking games: tip one like an ordinary jug and the drink spills out. The solution is hidden inside. In this design, a passage through the handle connects the drink to the rim. Cover the right openings, then suck through a spout instead of tipping. The pottery turns a wrong move into a practical joke.
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The planet with a comet-like tail
That fuzzy streak is not a comet: it is Mercury. Its tail appears in specially filtered, long-exposure photographs, making the smallest planet look as though it trails a comet. Sodium atoms escaping Mercury glow in sunlight, and sunlight pushes them away from the Sun into a tail. The same element gives some streetlights their yellow glow. As Mercury travels around the Sun, spacecraft measurements show changes in the tail’s brightness and extent.
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Letters folded into their own security locks
Before envelopes, people could turn a letter into its own lock. Folds, slits and paper strips secured the message and could show if it had been opened. Some designs threaded a strip cut from the letter through the folded packet. Researchers read a sealed letter from 1697 without opening it: X-ray scans captured its folds, and software unfolded the sheet virtually. The message survived, along with the original paper lock.
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A lizard with its own breathing bubble
Water anoles can dive in tropical streams and hide from predators while breathing through a bubble on the nose. Their water-repellent skin holds air: they exhale into the bubble, then breathe that air back in, repeating the cycle underwater. Researchers tested whether the bubble helps. Anoles able to rebreathe normally stayed submerged an average of 32% longer than lizards whose bubble formation was impaired, giving them more time underwater to hide.
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The mushroom that hunts microscopic worms
Oyster mushrooms are carnivores: the fungus behind this familiar food can paralyse microscopic worms called nematodes, then digest them for nutrients. The hunt takes place along fine fungal threads. Tiny lollipop-shaped structures contain a toxin; when a nematode touches one, it can be paralysed within seconds. The fungus grows into the immobilised worm and feeds on it, gaining nitrogen. Beneath a fallen log, those mushrooms may conceal a miniature hunting ground.
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A mirror with a secret in its reflection
An old bronze mirror holds an image of Buddha that appears on a wall when light shines on its polished face. The picture is concealed within the mirror, not visible as an ordinary design. Tiny distortions in the reflective surface, created during polishing above the hidden design, redirect the light to form the image. A CT scan revealed the concealed metalwork in detail; the picture was built into the object all along.
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