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  • You know the old saying.

  • That like people, no two snowflakes are exactly alike.

  • But is that really true?

  • Their intricate beauty is so delicateso fleeting.

  • It's made them one of nature's great mysteries.

  • But that incredible complexity actually comes from very simple building blocks.

  • High up in the clouds, snowflakes begin as water vapor.

  • Water molecules whiz around, bouncing off of each other.

  • When the temperature cools, the molecules slow down and start sticking to one another.

  • They form a hexagon: six-point symmetry, the core structure of a snowflake.

  • As each one grows, it builds on that basic geometry, creating a crystal lattice.

  • That's why you tend to find snowflakes with six arms.

  • Not five, not seven.

  • From there, the variety just explodes.

  • The shapes are practically infinite.

  • So what are the chances of finding two snow crystals that look exactly the same?

  • In his lab at Caltech, Physics professor Ken Libbrecht has figured out how to solve that mystery.

  • Inside a chamber, he makes snowflakes from scratch

  • He starts with humid air, and drops the temperature until ice crystals start to form.

  • When they get heavy enough they fall.

  • He catches them on a chilled plate, where he can watch them grow using time-lapse photography.

  • As he boosts the humidity, arms begin to extend out from the corners.

  • If he cools the air even more, branches shoot off the arms.

  • Libbrecht can create a bunch of crystals on the same plate.

  • Like these two, they're growing in exactly the same conditions.

  • And look!

  • Twins!

  • But these perfect copies only exist herein the lab.

  • Outside up in the clouds it's unpredictable.

  • The temperature, humidity and air pressure are constantly changing.

  • Each snowflake takes its own path as it falls to earth.

  • And that solo flight means they all grow a little... differently.

  • So each one really is unique, shaped by its own individual journey through the world.

  • Hey guys, it's Lauren.

  • We've got a few more tiny mysteries for you.

  • Find out how roly polies ventured out from the ocean to conquer your backyard.

  • Or how just one handful of sand can tell you the history of the entire planet.

  • And while you're at it, share us!

  • See you next time.

You know the old saying.

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B1 US snowflake temperature humidity lab air plate

Identical Snowflakes? Scientist Ruins Winter For Everyone. | Deep Look

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    Mackenzie posted on 2020/05/30
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