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为什么雪花总是六边形，却从不会是二边或五边形？

Snowflakes form when water vapor freezes directly onto tiny dust particles in cold clouds.
Water molecules arrange themselves in a hexagonal crystal lattice due to hydrogen bonding angles.
Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry.
Even tiny temperature or humidity changes alter branch growth but preserve the six-arm pattern.
No known natural ice crystal forms with two, five, or seven sides under Earth conditions.
Scientists have created pentagonal ice in labs using special substrates—but it’s unstable and melts instantly.
This consistency helps meteorologists classify snow types and predict storm behavior.
Photographing individual flakes reveals infinite variation within the rigid six-fold rule.
Computer models simulate how vapor diffusion shapes each arm independently yet symmetrically.
That universal geometry reflects deep physical laws—not random chance or design.