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Why Do Snowflakes Always Have Six Sides—But Never Two or Five?
为什么雪花总是六边形，却从不会是二边或五边形？
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Snowflakes form when water vapor freezes directly onto tiny dust particles in cold clouds.
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Water molecules arrange themselves in a hexagonal crystal lattice due to hydrogen bonding angles.
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Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry.
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Even tiny temperature or humidity changes alter branch growth but preserve the six-arm pattern.
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No known natural ice crystal forms with two, five, or seven sides under Earth conditions.
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Scientists have created pentagonal ice in labs using special substrates—but it’s unstable and melts instantly.
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This consistency helps meteorologists classify snow types and predict storm behavior.
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Photographing individual flakes reveals infinite variation within the rigid six-fold rule.
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Computer models simulate how vapor diffusion shapes each arm independently yet symmetrically.
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That universal geometry reflects deep physical laws—not random chance or design.