[2] Depending on environmental temperature and humidity, ice crystals can develop from the initial hexagonal prism into many symmetric shapes.
[1] The symmetric shapes are due to depositional growth, which is when ice forms directly from water vapor in the atmosphere.
[5] Small spaces in atmospheric particles can also collect water, freeze, and form ice crystals.
When squeezed between two layers of graphene, water forms square ice crystals at room temperature.
[22][23] The aerospace industry is working to design a radar that can detect ice crystal environments to discern hazardous flight conditions.
Ice crystals can melt when they touch the surface of warm aircraft, and refreeze due to environmental conditions.