Ice Crystals Facts

Ice crystals form when water freezes. This may be in the clouds, or near the ground. Temperature plays an important part in how the ice crystals form.

Structure

In an ice crystal, water molecules consisting of two hydrogen atoms for each oxygen atom form a hexagonal lattice.

Effects

Snowflakes or snow crystals form when ice crystals freeze around tiny particles of dust that are in the air, and join together as they fall. Ice crystals that melt as they fall become rain. Ice crystals that form near the ground are called frost.

Types

There are seven main types of ice crystals. They are: stellar (star shaped), plates, columns, capped columns, needles, spatial dendrite and irregular crystal.

Formation

Stellar and plate crystals form at 28 degrees and again at 5 degrees. Needle crystals form between 23 degrees and 27 degrees. Capped columns and columns form in the highest clouds at 30 degrees. Spatial dendrite crystals form between 3 degrees and 10 degrees. Irregular crystals form at various temperatures.

Benefits of Study

Studying ice crystals teaches how molecules condense to form crystals. It also teaches structure formation and self-assembly.

Fun Fact

Wilson Bentley, also known as "Snowflake Bentley," studied snowflakes all his life. He took more than 6,000 photographs, proving that no two ice crystals are exactly alike.

References

• Cal Tech Snowcrystal FAQ
• Eek Nature
• Alaska Science Forum

Resources

• Original images by Wilson Bentley