Mother Nature’s Snow Crystal Workshop
Johannes Kepler gave this gift, The Six-Cornered Snowflake, to the Holy Roman Emperor Rudolf II for New Years' back in 1611.
Stellar dendrite snow crystal, photographed on a piece of black fleece with an Olympus TG-6 camera. This is a great camera for macro-photography, with "stacking" software built in. Focus stacking is a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field than any of the individual source images.
That stellar dendrite crystal above is one of my favorite specimens I photographed in the Tennessee Appalachians in February, 2020. The term snow “crystal” is a more accurate way to describe individual snowflakes. The snow crystals may not be any larger than 2 to 3 millimeters in size. In fact, those big fluffy snow flakes that you may be familiar with are often made up of hundreds of individual branched snow crystals that lock together to make flakes like this quarter-sized beheamoth that crashed onto my deck one winter day.
Hexagonal plate (left) and embryo (right) photographed under a microscope, backlit by a LED flashlights with color filters (pieces of plastic page protectors) attached. Notice the 6-sided theme in every single crystal.
How Do They Form
It all starts with water, a really neat substance of nature. As you know, water is a molecule made up of 2 hydrogen and 1 oxygen atoms (H2O). In its solid state, these water molecules lock together into the 6-sided shape we all know and love as shown in this beautiful animation below. In this blog I am not going to get into all of the physics and chemistry associated with the complete processes that produce a snow crystal, but I will touch on some of the basic concepts.
(courtesy Kenneth Liebreccht, snowcrystals.com) |
You may all be familiar with the traditional snow crystal, that 6-armed Christmas ornament or piece of jewelry like the image below. In reality however there are many, many different types of snow crystals and it wasn't until I started photographing them that I really began to unlock the true miracle of this atmospheric factory that produces so many varieties. There are dendrites, plates, columns, capped-columns, prisms, needles, and other even more exotic designs.
Traditional 6-sided spatial dendrite that most people are familiar with when you mention the term snowflake. Note the amazing hexagonal symmetry that is maintained in so many designs as you move out from the center, or nucleus, of the crystal.
Snow crystals begin with a simple hexagonal prism having two basal facets, or sides, and six prism facets. Depending on a host of conditions withint the cloud, the crystal will either grow from the basil facet or the prism facet. If the ice nuclei grow outward in the hexagonal prism, you end up with a flat plate or dendrite crystal. Evetually, legs of the crystal then grow outward from one of the six points in the hexagonal plate, which “stick out” into the moist air just a bit more than the sides. If the crystal grows upward from the prism face, you get a hexagonal column as the crystal grows in a vertical manner as shown below.
Ukichiro Nakaya was one of the first scientists to develop a system for snow crystal formation. As a result of his research work back in the 1930s, he developed the Nakaya Diagram, which described the relationships between the humidity and temperature in the clouds and the type of snow crystal that forms. Although the physics behind snow crystal formation is exceptionally complicated, the basic ideas are shown in his chart below. What is so fascinating about the snow crystal is that its shape and design are a direct result of the atmospheric temperature and humidity profile it falls through on its way to earth. Nakaya so eloquently described the snow crystal as "A Letter From The Sky" because you could "read" the meteorological information "written" on the snow crystal.
Observing These Sculptures of Nature
Snow crystals on a fleece jacket. This photo was taken with a plain old iPhone 5, in a future bolg I will show you how to get started photographing your own snow crystals.
These crystal photographs are taken with the old microscope and Canon G-6 camera. They are post-processed to put them on nice backgrounds. The details that you can see in each crystal are truly amazing!
Spatial dendrite photos taken directly with my Olympus TG-6 camera. With this camera, you can get a much better look at the crystals in 3-D. The crystal on the left is attached to the hairs of an artist's paint brush. The threads in the background of the other images are the black fleece that I use to collect my specimens.
These snow crystals all have a few things in common. Each one of them is covered with all of those little frozen droplets. In one of my next blog entries I talk about how this process works. Stay tuned...
I plan to author a few more blog entries on snow crystals soon. They will include all of my instructions on how to get started photographing snow crystals, a nod to my snow crystal hero, Wilson Bentley, whom I consider the "Father of Snow Crystal Photography", and finally and extensive gallery of some of the hundreds of snow crystals I have photographed, and there are a few that are really "other-worldly. Stay tuned for that and much more!!
Real informative - crystals rock ...
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