That’s a totally cool (uh . . .) link, Maastricht, thanks! The snowflakes physics section is particularly fascinating! I’ve had that book on my Amazon wishlist for, like, years. I had no idea they had a website!
Ooh–Audobon did an article on snowflakes awhile back. I kept the mag just for the pics.
Lovely.
Cool, aren’t they? I’ve just treated myself to a 30 by 20 inch color poster from the same site.
This is one reason I like being Canadian. 
That’s beautiful!
However, since I’m the easily puzzled nitpicker, I’ll have to pick a nit with this odd passage from their Q&A section (italics are mine):
"Why is snow white?
Snow is made of small ice crystals, and close inspection reveals that the individual crystals are pretty clear. However when light travels from air to ice, or vice versa, some light is reflected (like the way light reflects slightly from a pane of glass). Since there are a lot of air/ice surfaces in a bank of snow, light shining into the snow get scattered about many times. After bouncing around a while inside the snow bank, some of the light scatters back out, and that is the light we see. Since all colors are scattered roughly equally well, the snow back appears white.
At this point you might be asking – If sunlight scatters off the snowbank, and sunlight is yellow, why doesn’t the snowbank then appear yellow instead of white? This, it turns out, is a deep and interesting question."
Excuse me? Since when did sunlight stop being white (or, to pick my own nit, very, very close to white)?
Still, wonderful site, great pictures.
Peak Banana, your username seems deeply significant in to the question in some way.
But anyway, if you look at the spectrum of the Sun, you can see that it peaks just shortward of .5 microns, or 500 nanometers, which is the yellowy-greeny part of the visible spectrum. The spectrum of a source of pure white light would be flat across the visible spectrum.
But that in turn begs the question: why does sunshine appear to be yellow?
certainly the sun looks yellow up in the sky. The golden slants of a setting sun across lawns and streets is one of my favorite sights.
Sunlight is yellow. Sky, blue. got it. But WHY (I know the bit about the sky, just in for filler).
And Monet once said that snow is any color BUT white when he was trying to paint some winter scenes–and he is right. Shadowed snow is shades of blue.
Sorry, eleanorigby, I don’t understand your question. Are you asking why the Sun’s spectrum is shaped like that (That’s easy! It’s a blackbody at T=5800K!), or why the Sun appears yellow to human eyes?
(Just kidding about the blackbody thing being easy. . . if that’s your question I, or other dopers, I’m sure, will be happy to explain.)
Um…I have forgotten just how your post begged the question posted in my post.
I think I meant, then why does snow look white? but really, given my brain, it could be anything, really.
PS-what the heck is a blackbody at T=5800K? It sounds to me like a cute black guy at the next mile marker… 
Are you one of those physics-type people?
<peers at Podkyne suspiciously>
The ones who tell me that X can happen, oh let X be the angle of force needed to pull a seal tab smoothly off a new jar of foodstuff and as we all know X does NOT come off in one smooth motion…or that a super ball just flat out can’t do Y when it has done exactly Y off my old roof…but I digress.
A blackbody is an object that emits light at all wavelengths because it’s hot. Lots of things are blackbodies, like stars . . . houses . . . rocks . . . people . . .
Imagine a person holding a bar of iron in his hand. When it’s room temperature, it doesn’t appear to glow; that’s because it’s emitting very little visible light—so little it’s undetectable to your eye. But if you could look at it with an infrared camera, you’ll see it’s emitting a lot of infrared light—just like the person who’s holding it. But since the person is just a tad warmer than room temperature, the person will emit more light, and look brighter to your IR camera. And they will be emitting light that has slightly more energy on average.
Now, if the person takes some tongs (very important safety equipment!) and holds that bar of iron in a forge, the bar will heat up, and it will start to emit enough visible light that it will actually appear to glow. First it will glow a dull red, but as it gets hotter and hotter, it will emit photons of greater and greater energy, so it will go from red to orange—and it will get brighter too. When it reaches the same temperature as the surface of the Sun, 5800 Kelvins, or 10,800 degrees Fahrenheit, it will be glowing yellow, just like the Sun does, and it will be as bright as the Sun, too, uncomfortable to look at with your naked eye.
You’re right that physics often doesn’t translate very well into the real world, but the Sun is actually a pretty good blackbody; the shape of its spectrum is very close to that which is theoretically predicted for a blackbody, except that some of the light of the Sun is absorbed by gas in its atmosphere, and in the Earth’s atmosphere.
So, now you see, I’m much, much worse than one of those physics people . . . I’m an astrophysics people!!!
Which explains the hotness of Denzel Washington…hee.
small hijack–my Trignometry teacher (horrible man, really) started the year with these words: “Imagine a unit circle with a radius of one (one what was never stipulated)”. He lost me from there. Not real pertinent to the discussion at hand, but I wanted to share.
Are you just taking a long time to say that I’m a little ray of sunshine in your life?
(just messing with you)
We can heat shi–I mean stuff up the heat of the sun? [johnny carson voice] I did not know that[/johny carson voice] But THAT begs the question–what is it about that particular light wave or spectrum or whatever that is uncomfortable to the human eye? Have we got shit for cones and rods or what? 
I concur with my illustrous colleague that tongs are indeed a vital piece in the arsenal of scientific research personal protective devices.
Oh, I know that physics IS the real world. Just 'cause I got a bad grade in my correspondence physics course in college has NOTHING to do with my rancorous attitude towards it. No, really… 
:eek:
And to make it worse–you seem a nice bus riding physics-type person. What is the world coming to? 
Back to the snow…
The other day it was just the right kind of snowfall for me to stand outside and stare at the flakes landing on my black wool coat and marvel at how pretty they were. People were looking at me funny, but a few of them glanced down at their coats and smiled at the accumulating flakes. It’s impossible** not **to be happy when there’s a snow like that.