How ice crystals create optical illusions

By 2015-01-01T10:48:00

A close-up photograph of ice crystals in frost

Source: © Getty Images

From light pillars and sun haloes to false suns, explore the mysterious effects ice crystals can produce when they interact with light.

If ice crystallises slowly, a single crystal can form. Crystals like this are often produced in the atmosphere but can have many different shapes. Some make columns, some make plates and others form the familiar snowflake. What all of these have in common is that their shapes are based on hexagons.

It is ice crystals like these that cause interesting visual effects when they interact with light from the sun. Light pillars, sun haloes and even parhelia or ‘false suns’ – read on to find out what’s behind these optical illusions in the sky.

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