HE MAKES HIS OWN SNOWFLAKES
Courier-Post, Cherry Hill, N.J.
Published: 3/2/2003
The great thing about a blizzard is that, no matter what else is going on, snow is suddenly your biggest problem and really, it's not that big a problem.
You have to drive slowly, sometimes you slip on the pavement, blah, blah, blah. But now most of the snow from the last storm in New Jersey has melted, which leaves us with what had been our second-biggest problem: America is going to war, possibly by the time you read this. We need more snow.
That's where Kenneth G. Libbrecht comes in. He makes his own snowflakes.
It just popped into my head one day, about six years ago, that I'd never seen an artificial snowflake, said the physics professor who works at the California Institute of Technology in southern California but comes from North Dakota. I began reading up on the physics of snow crystals and was surprised to discover how many unsolved problems there were. So I started doing experiments, and calculating things, and I'm still working on it.
A small part of Libbrecht's work in atomic physics, the snowflake project falls into the scientific category of studying how crystals grow or, as his Web page puts it, pattern formation in nonlinear nonequilibrium systems. To look at it another way, from watching how snowflakes develop, we might build better semiconductors.
Growing flakes is apparently simple enough. You need an empty, 20-ounce plastic Coke bottle, three large-diameter Styrofoam cups, a small kitchen sponge about half-an-inch thick, a short piece of nylon fishing line, a sewing needle, four straight pins, a paper clip, some paper towels and crushed dry ice.
Libbrecht's Web page which also has pictures of his snowflakes shows you how to put it all together. Basically, you stick the Coke bottle upside down into the cups and make it warm at the top and cold at the bottom. The flakes grow on the needle as it hangs inside the bottle. Professor Libbrecht grew one snowflake this way to be about an inch in diameter. And hes
he's also been experimenting with electricity.
In certain cases, he would start with a regular ice crystal, then slowly turn up the voltage on the needle upon which the crystals were growing. The tips on the snowflake would grow sharper and faster. Once the voltage got high enough, the tips would split, then those two branches would split again. At the highest rate of voltage, the ice needles became bent and gnarled, like sticker branches.
And there you have it mutant, Frankenstein snowflakes that either will crowd out other snowflakes through natural selection because of their superior snowflakeness or else be sad outcasts, spending their short lives asking why they have been brought into the world only to suffer and be afraid.
And not just mutants clones. Under laboratory conditions, Libbrecht has created two or more snowflakes that are by one definition, anyway alike.
No, they're not the same molecule-for-molecule. But as for making two flakes that appear alike under the microscope, yeah, he's done it mostly by keeping them small, he said. They are simple hexagonal flakes less than 100 microns or so, less than the thickness of a sheet of paper. They tend to become more complex as they grow larger.
A snowflake takes shape mainly according to the temperature fluctuations it undergoes as it develops. Even the smallest shift in temperature can change everything. But in theory, Libbrecht confirmed, if you can keep the temperature patterns absolutely consistent in a laboratory or, say, Antarctica larger, more developed flakes could come out alike as well.
I dream of that: drifts of twisted, electrified snowflakes, each one exactly the same, programmed to do my bidding. The world could be at peace if we all had just one snowflake we could agree on.
Then once the weather warms up, I could go look for someone maybe at a 7-Eleven who makes his own slush.
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