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A meteorite carries a pattern millions of years old
These geometric lines grew inside an asteroid. In some iron meteorites, metal crystals formed as the interior cooled over millions of years. Cutting, polishing and etching the metal reveals the pattern. A slice of space, carrying a record of slow cooling.
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Unzipping a Velvet Eclipse
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A leafless plant lives almost entirely underground
This alien-looking flower belongs to a plant with no leaves. Hydnora africana lives mostly underground, taking nutrients from other plants' roots instead of making food from sunlight. Its foul-smelling bloom lures beetles to pollinate it. Strange, but real.
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Rolling a Pebble Choir
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Sticky tape became an unlikely source of X-rays
Scientists made X-rays by peeling sticky tape. In a vacuum, separating the sticky surfaces builds an electrical charge. When it discharges, it can emit X-rays. The effect was strong enough to make an X-ray image of a finger. An office supply, doing physics.
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There are lakes at the bottom of the ocean
There are lakes at the bottom of the ocean. Extra-salty water is so dense that it pools beneath ordinary seawater, creating a distinct surface and shoreline. Some even have waves. A lake inside the sea, with water above its water.
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The cuttlefish that changes the shape of its skin
This cuttlefish can change the actual texture of its skin. Tiny muscular bumps rise and flatten, turning a smooth body into something that looks like rock or seaweed. Its camouflage isn't just a new colour. It's a new shape.
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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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