Search Teaching about Snowflakes: A Flurry of Ideas for Science and Math Integration Did you know that while no two snowflakes are exactly the same, they are all six-sided? Image by Wilson A. As you might know, each water molecule is made of two hydrogen atoms bonded to one oxygen atom and looks something like this:
Snow science Naturally formed snowflakes differ from one another through happenstance of formation. The characteristic six branches is related with the crystal structure of ice. They grow by net accretion to the incipient crystals in hexagonal formations.
The cohesive forces are primarily electrostatic. Nucleus[ edit ] In warmer clouds, an aerosol particle or "ice nucleus" must be present in or in contact with the droplet to act as a nucleus. The particles that make ice nuclei are very rare compared to nuclei upon which liquid cloud droplets form; however, it is not understood what makes them efficient.
Clays, desert dust, and biological particles may be effective,  although to what extent is unclear. Artificial nuclei include particles of silver iodide and dry iceand these are used to stimulate precipitation in cloud seeding. Once a droplet has frozen, it grows in the supersaturated environment, which is one where air is saturated with respect to ice when the temperature is below the freezing point.
The droplet then grows by deposition of water molecules in the air vapor onto the ice crystal surface where they are collected. Because water droplets are so much more numerous than the ice crystals due to their sheer abundance, the crystals are able to grow to hundreds of micrometers or millimeters in size at the expense of the water droplets.
This process is known as the Wegener—Bergeron—Findeisen process. The corresponding depletion of water vapor causes the droplets to evaporate, meaning that the ice crystals grow at the droplets' expense. These large crystals are an efficient source of precipitation, since they fall through the atmosphere due to their mass, and may collide and stick together in clusters, or aggregates.
These aggregates are usually the type of ice particle that falls to the ground. Although this report by a farmer is doubtful, aggregates of three or four inches width have been observed.
Single crystals the size of a dime Color[ edit ] Snow crystals in strong direct sunlight act like small prisms Although ice by itself is clear, snow usually appears white in color due to diffuse reflection of the whole spectrum of light by the scattering of light by the small crystal facets of the snowflakes of which it is comprised.
It is unlikely that any two snowflakes are alike due to the estimated 10 quintillion water molecules which make up a typical snowflake,  which grow at different rates and in different patterns depending on the changing temperature and humidity within the atmosphere that the snowflake falls through on its way to the ground.
The symmetry gets started  due to the hexagonal crystalline structure of ice. At that stage, the snowflake has the shape of a minute hexagon. The six "arms" of the snowflake, or dendrites, then grow independently from each of the corners of the hexagon, while either side of each arm grows independently.
The microenvironment in which the snowflake grows changes dynamically as the snowflake falls through the cloud and tiny changes in temperature and humidity affect the way in which water molecules attach to the snowflake.
Since the micro-environment and its changes are very nearly identical around the snowflake, each arm tends to grow in nearly the same way. However, being in the same micro-environment does not guarantee that each arm grow the same; indeed, for some crystal forms it does not because the underlying crystal growth mechanism also affects how fast each surface region of a crystal grows.
Although nearly-identical snowflakes have been made in laboratory, they are very unlikely to be found in nature. Ukichiro Nakaya developed a crystal morphology diagram, relating crystal shape to the temperature and moisture conditions under which they formed, which is summarized in the following table:Twelfth Century philosopher Zhu Xi theorized why snowflakes are always six-sided when he wrote: "The reason why snowflakes are six-pointed is because they are only half-frozen rain (xian) (i.e.
water) split open by violent winds, and so they must be six-pointed. Snowflake Explorers For as long as humans have inhabited the Earth we have been both fascinated and frustrated by snow, ice and adverse weather conditions. With the invention of the microscope, the tiny mysterious crystals of ice have been brought into focus as stunningly beautiful and still quite mysterious.
A stylized snowflake has been part of the emblem of the Winter Olympics, Winter Olympics, Winter Olympics, Winter Olympics and Winter Olympics.
Snowflakes are also seen as a symbol of . Snowflakes that look identical, but may vary at the molecular level, have been grown under controlled conditions.
The snowflake makes its first appearance in recorded history when people identified individual snow crystals—with their distinctive six-fold symmetry—as the constituent elements of falling snow. Diy Snowflakes Snowflake Cutouts Snowflake Diy Paper Snowflake Schema How To Fold Snowflakes Snowflakes Diy Template Paper Snowflake Patterns Snowflake Party Christmas Snowflakes Forward Try out this snowflake paper cutting idea and attach to string to hang from your shop ceiling or shelves. Snowflake Trivia and Resources Earliest Mentions of Snow Formation The first mention of the hexagonal form in relation to a snow crystal was made by Han Ying in BC, in the publication "Hanshi waizhuan" (Moral Discourses Illustrating the Han text of .
Although snowflakes are never completely symmetrical, a non-aggregated snowflake often grows so as to exhibit an approximation of six-fold radial symmetry.
Diy Snowflakes Snowflake Cutouts Snowflake Diy Paper Snowflake Schema How To Fold Snowflakes Snowflakes Diy Template Paper Snowflake Patterns Snowflake Party Christmas Snowflakes Forward Try out this snowflake paper cutting idea and attach to string to hang from your shop ceiling or shelves.
Here are some highlights in the study of snowflakes and snow crystals. -- Johannes Kepler: In Johannes Kepler published a short treatise On the Six-Cornered Snowflake,  which was the first scientific reference to snow crystals.
Kepler pondered the question of why snow crystals always exhibit a six-fold symmetry.