So if the scorpion is out in the open, it will glow and be easy to spot because there isn’t much other blue or green light around. Has gone and only the ultraviolet is left. Ultraviolet light is around all the time, but at dusk, when the sun has just slipped below the horizon, most of the visible light To be an adaptation to help the scorpions find the best hiding places at dusk. The name for this trick of the light is fluorescence. It’s a reallyĬlever technique, although if you’re scared of scorpions to start with, your appreciation might be a little muted. These black arachnids have pigments in their exoskeleton that take in ultraviolet light that we can’t see and give back visible light that we can see. Then there’s a flash, and the darkness of the desert is punctured by a surprised scuttling patch of eerie Roams across the ground, it’s impossible to tell exactly where it’s pointing because it’s invisible. The flashlight needs to be one that produces light that is invisible to our species: ultraviolet light, or “black light.” As the beam You equip yourself with a special flashlight and set out into the darkness. Finding anything out here seems close to impossible, since the ground is lit only by dim starlight. But they both use the same scientific trick to survive, although in opposite ways.Ī moonless night in the North American desert is cold and quiet. Scorpions and cyclists have much in common. But sometimes the connection goes a little bit deeper and so it’s all the more satisfying when it finally emerges. Sometimes a pattern is easy to spot in new places. Science: the continual refinement and testing of our understanding, alongside the digging that reveals even more to be understood. Hidden beneath both is a systematic basis for all such formations, one discovered and explored and tested by rigorous experiments carried out by generations of humans. It’s a clue that hints at something more fundamental. We know these swirls as depressions or cyclones,Īnd we experience rapid changes between wind, rain, and sunshine as the arms of the spiral spin past.Ī rotating storm might seem to have very little in common with a stirred mug of tea, but the similarity in the patterns is more than coincidence. The cool and warm air chase each other around in circles, and you can see the pattern clearly on satellite images. North and warm tropical air to the south. They form at the boundary between cold polar air to the In Britain, these swirls come rolling across the Atlantic from the west on a regular basis, causing our notoriously changeable weather. If you look down on the Earth from space, you will often see very similar swirls in the clouds, made where warm air and cold air waltz around each other instead of mixingĭirectly. But it was there for long enough to be seen, a brief reminder that liquids mixin beautiful swirling patterns and not by merging instantaneously. In your teacup, the spiral lasts just a few seconds before the two If you pour milk into your tea and give it a quick stir, you’ll see a swirl, a spiral of two fluids circling each other while barely touching. Principles and the same atoms combining in different ways to produce a rich bounty of outcomes. The physical world is full of startling variety, caused by the same This is the place to look if you’re interested in what makes the universe tick. Our home here on Earth is the opposite: messy, changeable, bursting with noveltyĪnd full of things that we touch and tweak every day. Every human civilization has seen the stars, but no one has touched them. Landmarks unique to our place in the cosmos. On a clear night, anyone can admire the vast legions of bright stars, familiar and permanent, WE LIVE ON the edge, perched on the boundary between planet Earth and the rest of the universe. “Ooh,” she said, “and what can you do when you know that?” Nana, a down-to-earth northerner, was very impressed when I told her that I was studying the structure of the atom. While I was a university student, I spent a while doing physics revision at my Nana’s house. Transkrypt (Ē5 z dostępnych 52 stron) STRONA 3
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