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The Wikipedia Image of the Day

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Feb. 28th, 2007 | 02:15 pm

...is a very cool electron microscope magnification of a snow crystal:

http://en.wikipedia.org/wiki/Image:LT-SEM_snow_crystal_magnification_series-3_frame.jpg

We don't design things that are so much larger than this with half as much elegance.

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Comments {11}

Comfort me with Apples

(no subject)

from: tanaise
date: Feb. 28th, 2007 07:25 pm (UTC)
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I was going to say it looks like a sf enclave on a polar planet. But then when I looked at the picture, I realized it really looks more like Lexx.

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sacwentie

(no subject)

from: sacwentie
date: Feb. 28th, 2007 08:03 pm (UTC)
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wow. thanks for posting

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The Wayfarer

(no subject)

from: mnfaure
date: Feb. 28th, 2007 08:11 pm (UTC)
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Wow. Thanks for sharing!

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sallytuppence

(no subject)

from: sallytuppence
date: Feb. 28th, 2007 08:14 pm (UTC)
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My new desktop background.

Thanks, Charlie!

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godsdelight

Cool! (no pun intended)

from: godsdelight
date: Feb. 28th, 2007 08:33 pm (UTC)
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The more we know about the natural world, the more amazing it is.

For some reason, the Wikipedia page didn't let me zoom in on all the parts of the picture (it only zoomed to one section). Here's another link to the same image, but with the ability to zoom in further and further on a particular section:

http://emu.arsusda.gov/snowsite/magnification/magnification.html

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(no subject)

from: battle_of_one
date: Feb. 28th, 2007 08:54 pm (UTC)
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That is SO gorgeous!

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(no subject)

from: ruvdraba
date: Feb. 28th, 2007 09:56 pm (UTC)
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This is brill!

Does someone happen to know why snowflake crystals have such elegant symmetry? It wouldn't be remarkable except that each crystal looks different from others, yet its own arms are the same.

It always looks like each "arm" of the crystal is conferring with the other arms as it grows, to decide what to do next.

Presumably, the information that decides what the arms are doing has to be "decided" at the "heart" of the crystal before the arms begin growing. But how does that happen? And how many possibilities are there?

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godsdelight

dude, what a thought!

from: godsdelight
date: Mar. 1st, 2007 04:42 am (UTC)
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Huh... snow crystal DNA? And if there is such a thing... does it have relational patterns (parents, grandparents, generational ancestry with similar pieces of pattern -- yet always in unique combinations)?

Interesting thought... Could use it for the basis of a crystal-based lifeform in a sci-fi story, eh? (prolly been done, I suppose)

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Answering my own dang question...

from: ruvdraba
date: Mar. 1st, 2007 05:27 am (UTC)
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From the wikipedia entry on snow.


There are, broadly, two possible explanations for the symmetry of snowflakes. First, there could be communication or information transfer between the arms, such that growth in each arm affects the growth in each other arm. Surface tension or phonons are among the ways that such communication could occur. The other explanation, which appears to be the prevalent view, is that the arms of a snowflake grow independently in an environment that is believed to be rapidly varying in temperature, humidity and other atmospheric conditions. This environment is believed to be relatively spatially homogeneous on the scale of a single flake, leading to the arms growing to a high level of visual similarity by responding in identical ways to identical conditions, much in the same way that unrelated trees respond to environmental changes by growing near-identical sets of tree rings. The difference in the environment in scales larger than a snowflake leads to the observed lack of correlation between the shapes of different snowflakes. The sixfold symmetry happens because of the basic hexagonal crystalline structure from which the snowflake grows. Surprisingly, the exact reason for the threefold symmetry of triangular snowflakes is still a mystery.


The "common small-scale environment" explanation seems sensible, but the phonons explanation has the interesting story in it. Neither of them, alas, is a "snowflake DNA" explanation. :(

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godsdelight

Re: Answering my own dang question...

from: godsdelight
date: Mar. 1st, 2007 05:50 am (UTC)
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Interesting concepts, both. The environmental explanation could still apply in interesting ways to crystalline lifeforms... imagine a species where you could tell where and when they were born based on their looks. Not so different from humanity, I suppose, in some ways.

Huh. Still seems like you'd have the same environmental conditions happen pretty often... there must be micro differences that have major impacts on the flake's look. What a sensitive little creation a snowflake must be, to become something so unique when surrounded by so many siblings, all based on the same batch of cloud-collected moisture.

Gotta stop thinking about this..! Either that, or become a crystallographer and spend the rest of my life pursuing the answer. The crystalline children of a billion snowstorms cry out to us! All these astounding little individuals melting away on some toddler's tongue or dissolving into a slushpile on the side of the interstate. Oh, the humanity--er, the hydronity!

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Wendy S. Delmater

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from: safewrite
date: Mar. 1st, 2007 04:29 am (UTC)
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How beautiful. Thank you for my dose of sensawunda for the day.

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