Snow under the Microscope
We can all conjure the classic image of a snowflake in our minds. But did you know there are a vast number of different snowflakes? They are both surprising and utterly breathtaking in their diversity and beauty. Let’s look at some of my favorites and how you can spot them.
Which magnifier?
A simple, cheap magnifying glass of at least 5x magnification will work well for most snowflake hunting and fits in your pocket. A jeweler’s loupe will cost more but will give you a clearer, more defined image. Go for at least a 7x rating. The most expensive option, but one that will yield the most detailed and impressive results, is a microscope, which gives you a field of vision of around 3 mm and at least 20x magnification across two eyepieces. You can catch your snowflakes on a piece of cardboard or colored packaging before having a closer look. [Here’s] a guide to some of the extraordinary shapes you might find.
- Diamond dust crystal
Also known as ice crystals, these form close to the ground in extremely cold weather and sparkle magically in the sunlight.
- Stellar dendrite
This star-shaped snow crystal has six branches and lots of smaller branches coming off each of those. “Dendrite” means treelike.
- Triangular crystal
These are wonderful and mysterious – science has still not entirely worked out what conditions cause the formation of these cool crystals.
- 12-sided snowflake
These occur when two six-sided snowflakes collide in midair and stick together!
- Capped column
These wonderful shapes form when the snowflake travels through different temperatures as it grows.
- Rimed snowflake
These are snowflakes that have collided with tiny water droplets, called rime.
Finding nature’s numbers
Out in the snowy winter, the magic of nature’s repeating patterns is all around. Let’s look a bit closer…
- The Fibonacci sequence
This fascinating sequence was presented in 1202 by Leonardo Fibonacci and is very simple: start with number 1 and add the previous number (1, 1, 2, 3, 5, 8, 13, 21, 34 and so on). We can also see the Fibonacci spiral emerge as we draw quarter-circle arcs across the numbers from his famous sequence. The number sequence and spiral crop up everywhere in nature, from the number of petals on flowers to shells, cobwebs and even galaxies! In the snowy winter landscape, find a pine cone, look at it from the bottom and count the spirals going in each direction. You will find that the number of spirals going in both directions can be found in Fibonacci’s sequence. Where else can you find these magical numbers in nature?
- Tree fractals
Fractals are geometric shapes that repeat their patterns in ever-finer scales. Think of a river. Its natural branching form, splitting off into smaller and smaller streams, is a fractal pattern, just like the shape of a cauliflower or the branches of a tree. A deciduous tree, when viewed in the winter without leaves, reveals its glorious fractal architecture. The pattern is simple: the trunk splits into two branches, which then split into two smaller ones and so on. Fascinatingly, most trees have no more than 11 of these splits on any one branch. Head out and count them!
- Da Vinci’s Rule for Branches
Leonardo da Vinci wrote, “All the branches of a tree at every stage of its height when put together are equal in thickness to the trunk.” Put another way, if you cut the branches at any one height on the tree and added them together, they would add up to the same size as the tree’s trunk. This is mind-blowing: it means that if the tree were squeezed upward with all the branches brought into the center, it would be the same thickness throughout! It has since been shown not to be true in absolutely every case but is still very cool!
Spot crown shyness
As your boots crack through a frozen puddle and crunch through the snow on a winter walk in the woods, take a moment to look up and spot one of nature’s many wonders – crown shyness. This occurs in a forest when the crowns of trees avoid touching each other, creating boundaries and clear channel-like gaps in the canopy. There are a number of different theories as to the cause of crown shyness, such as trees minimizing harmful competition for light or inhibiting the spread of leaf-eating insect larvae and disease. Whatever the reason, the results are quite beautiful. Enjoy.
Excerpted with permission from 50 Things to Do in the Snow by Richard Skrein © 2024. Published by Princeton Architectural Press a division of Chronicle Books. Illustrations by Maria Nilsson.
