Professor Thomas Koop is steamed. A physical chemist at Bielefeld University in Germany, Koop was fed up with the incorrect depictions of “designer snowflakes” that don’t have the omnipresent six-fold symmetry (there are rare exceptions; one is shown below), and so he wrote a letter that was published in in last week’s Nature and highlighted in The Guardian. At first I thought, well, here’s a guy with too much time on his hands, but then realized that he’s making a point that simply adds to our appreciation of the natural world.
Parts of the world are once again knee-deep in images of snow crystals for the Christmas and New Year festivities. Unfortunately, the grand diversity of naturally occurring snow crystals is commonly corrupted by incorrect ‘designer’ versions — as illustrated by the faux octagonal snowflakes depicted in a Nature online subscription advertisement and, ironically, captioned “…for anyone who loves science”.
The snowflake’s natural sixfold symmetry stems from the water molecules’ hexagonal crystal lattice, held together by a hydrogen-bonding network and the structural form of lowest energy under the ambient cold conditions. This hexagonal shape has been known since at least 400 years ago, when the astronomer Johannes Kepler published a treatise on the subject On the Six-cornered Snowflake (De nive sexangula Tampach; 1611), as a new-year’s gift to his patron — modern editions are still available.
Beautiful photographs abound, including those taken by Vermont farmer Wilson A. Bentley starting in 1885 (W. A. Bentley & J. Humphreys Snow Crystals McGraw-Hill; 1931), or see http://www.snowcrystals.com. Why then do many artists invent their own physically unrealistic snow crystals?
We who enjoy both science and captivating design should aim to melt away all four-, five- or eight-cornered snow crystals from cards, children’s books and advertisements, by enlightening those who unwittingly generate and distribute them. Let’s welcome this as an opportunity to share a discussion about the true beauty of science over a mug of hot punch.
And yes, it’s true that nobody has ever found two snowflakes that are alike. Nor are all of them symmetrical. Before the snow goes away, you might want to visit the SnowCrystals website, learn how snowflakes are formed, and see some lovely photos.
First, one of the many bogus and scientifically incorrect snowflake (don’t let your kids see these!), and then the real things (images from SnowCrystals.com):
(Cick here to see the world’s smallest snowman.)
Click this link to see non-hexagonal snow forms: 3-sided, 12-sided, dual prisms, etc.
Still, no 8-sided ones.
What is this blasphemy?
I love the snow crystals website and always envied all those cameras, refrigerators, and so on. I hope you obtained permission to post those photos though; some attribution would be good too (unless the owner asked not to me mentioned).
Yes, I checked for permission, and on the website it says this: If you want to publish something from this website on your personal website or blog, that’s fine, but please include a link to SnowCrystals.com. So of course I included a link
My guess is that 8-sided “designer” snowflakes show up because it’s easier to fold a rectagonal piece of paper for cutting something with 8 symmetrical sides than it is to fold that same piece of paper to cut out something with six symmetrical sides. 90 qand 45 degree folding is easier (you’ve got the original angles of the paper to go by) than 120, 60 or 30 degrees.
They really are beautiful: an illustration of how some simple restrictions on chemical bonding can generate intricate and, dare I say it, seemingly complex patterns.
Well, he has a point. Or perhaps six of them.
Why would you want to depict nature with faux physics? Why, that would be like having animated movies that shows Donald Duck falling free only when he becomes aware of the unavoidable outcome of his misstep.
Folk physics is endlessly fascinating, often annoying and sometimes dangerous. But I agree that this otherwise rather harmless Nature example overstepped the bounds.
[The reason why artists choose octagonal flakes is likely one of ease of production of that particular symmetry, as in so many cases of art. (In fact, I believe I’ve heard that defense from an artist the other winter.)
Call it “symmetry rendering”, and think of how for example digital rendering in its various forms fakes experience wholesale anyway.
The artists relies on that non-physicists wouldn’t know the minor falsehood anyway.]
Duh! Sorry YNNB?, didn’t mean to step in your snowy but not flaky footprints – I should have updated before posting.
No flora or fauna were harmed, either in making or the destruction of the above snowflakes.
This got me wondering about “snow” on other planets, and a quick google found this page about CO2 snow on Mars.
Couldn’t find anything about methane snowflakes on Titan — any chemists care to speculate?
Here’s hoping that I haven’t overstepped the bounds of good taste…
… but I believe Professor Koop may have a point:
Oh well, can’t find the right HTML tags to post a picture.
http://i45.tinypic.com/117dbtc.jpg
I have a friend who is very science-oriented, but who has a lighted 5-armed “snowflake” in his window for the holiday season. It drives me nuts…